U.S. patent application number 14/962715 was filed with the patent office on 2016-03-31 for prodrugs of gaba analogs, compositions and uses thereof.
This patent application is currently assigned to XENOPORT, INC.. The applicant listed for this patent is XENOPORT, INC.. Invention is credited to Mark A. Gallop.
Application Number | 20160090353 14/962715 |
Document ID | / |
Family ID | 37083911 |
Filed Date | 2016-03-31 |
United States Patent
Application |
20160090353 |
Kind Code |
A1 |
Gallop; Mark A. |
March 31, 2016 |
PRODRUGS OF GABA ANALOGS, COMPOSITIONS AND USES THEREOF
Abstract
The present invention provides prodrugs of GABA analogs,
pharmaceutical compositions of prodrugs of GABA analogs and methods
for making prodrugs of GABA analogs. The present invention also
provides methods for using prodrugs of GABA analogs and methods for
using pharmaceutical compositions of prodrugs of GABA analogs for
treating or preventing common diseases and/or disorders.
Inventors: |
Gallop; Mark A.; (Palo Alto,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
XENOPORT, INC. |
Santa Clara |
CA |
US |
|
|
Assignee: |
XENOPORT, INC.
Santa Clara
CA
|
Family ID: |
37083911 |
Appl. No.: |
14/962715 |
Filed: |
December 8, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14792243 |
Jul 6, 2015 |
9238616 |
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14962715 |
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13714224 |
Dec 13, 2012 |
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14792243 |
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13274278 |
Oct 14, 2011 |
8367722 |
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13714224 |
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11110909 |
Apr 6, 2005 |
8048917 |
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13274278 |
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10459242 |
Jun 10, 2003 |
6972341 |
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11110909 |
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10171485 |
Jun 11, 2002 |
6818787 |
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10459242 |
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60366090 |
Mar 19, 2002 |
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60298514 |
Jun 14, 2001 |
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60297521 |
Jun 11, 2001 |
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Current U.S.
Class: |
514/561 ;
562/505; 562/507 |
Current CPC
Class: |
C07C 2601/04 20170501;
A61P 25/22 20180101; C07C 271/22 20130101; C07C 2601/14 20170501;
C07C 229/28 20130101; C07C 2601/18 20170501; A61P 25/32 20180101;
A61P 25/00 20180101; A61K 31/24 20130101; A61P 25/08 20180101; A61K
31/22 20130101; C07C 309/29 20130101 |
International
Class: |
C07C 229/28 20060101
C07C229/28 |
Claims
1. A compound of Formula (I): ##STR00063## or a pharmaceutically
acceptable salt thereof, wherein n is 0; each of R1, R3, R6 and R7
is hydrogen; Y is oxygen; and R4 and R5, together with the carbon
atom to which they are attached, form a cyclobutyl ring that is
substituted with an ethanyl-substituted C.sub.2-C.sub.4 alkenyl
moiety.
2. The compound of claim 1, wherein the ethanyl-substituted
C.sub.2-C.sub.4 alkenyl moiety is an ethanyl-substituted propenyl
moiety.
3. The compound of claim 2, comprising a pharmaceutically
acceptable salt.
4. The compound of claim 3, wherein the salt is a benzene sulfonic
acid salt.
5. A pharmaceutical composition comprising a therapeutically
effective amount of a compound of claim 1.
6. A method for treating epilepsy, depression, anxiety, psychosis,
faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain, inflammatory disease,
insomnia, gastrointestinal disorders or ethanol withdrawal syndrome
in a patient, comprising administering to a patient in need of such
treatment a therapeutically effective amount of a compound of claim
1.
7. The method of claim 6, comprising treating pain.
8. The method of claim 7, comprising treating neuropathic pain.
9. The method of claim 6, for treating anxiety.
10. The method of claim 6, for treating epilepsy.
11. A compound of Formula (XIII): ##STR00064## wherein each of R3
and R6 is hydrogen; R4 and R5, together with the carbon atom to
which they are attached, form a cyclobutyl ring that is substituted
with an ethanyl-substituted C2-C4 alkenyl moiety.
12. The compound of claim 11, comprising a pharmaceutically
acceptable salt.
13. The compound of claim 12, wherein the salt is a benzene
sulfonic acid salt.
14. A compound of Formula (XIII): ##STR00065## wherein each of R3
and R6 is hydrogen; R4 and R5, form a substituted C4-C7 cycloalkyl
that is a bicyclic.
15. The compound of claim 14, comprising a pharmaceutically
acceptable salt.
16. The compound of claim 14, wherein the salt is a benzene
sulfonic acid salt.
Description
[0001] This application claims the benefit under 35 U.S.C.
.sctn.120 from U.S. patent application Ser. No. 14/792,243, filed
Jul. 6, 2015, which claimed the benefit under 35 U.S.C. .sctn.120
from U.S. patent application Ser. No. 13/714,224, filed Dec. 13,
2012, which claimed the benefit under 35 U.S.C. .sctn.120 from U.S.
patent application Ser. No. 13/274,278, filed Oct. 14, 2011, now
U.S. Pat. No. 8,367,722, which claimed the benefit under 35 U.S.C.
.sctn.120 from U.S. patent application Ser. No. 11/110,909, filed
Apr. 6, 2005, now U.S. Pat. No. 8,048,917, which claimed the
benefit under 35 U.S.C. .sctn.120 from U.S. patent application Ser.
No. 10/459,242, filed Jun. 10, 2003, now U.S. Pat. No. 6,972,341,
which claimed the benefit under 35 U.S.C. .sctn.120 from U.S.
patent application Ser. No. 10/171,485, filed Jun. 11, 2002, now
U.S. Pat. No. 6,818,787, which claimed the benefit under U.S.C.
.sctn.119(e) from U.S. Provisional Application Ser. No. 60/297,521,
filed Jun. 11, 2001; U.S. Provisional Application Ser. No.
60/298,514, filed Jun. 14, 2001; and U.S. Provisional Application
Ser. No. 60/366,090, filed Mar. 19, 2002, which are herein
incorporated by reference in their entireties.
FIELD OF THE INVENTION
[0002] The present invention relates generally to prodrugs of GABA
analogs, pharmaceutical compositions of to prodrugs of GABA
analogs, methods of making prodrugs of GABA analogs, methods of
using prodrugs of GABA analogs and pharmaceutical compositions of
prodrugs of GABA analogs. More particularly, the present invention
relates to prodrugs of gabapentin and pregabalin, pharmaceutical
compositions of prodrugs of gabapentin and pregabalin, methods of
making prodrugs of gabapentin and pregabalin, methods of using
prodrugs of gabapentin and pregabalin and pharmaceutical
compositions of prodrugs of gabapentin and pregabalin.
1. BACKGROUND OF THE INVENTION
[0003] Gamma (".gamma.")-aminobutyric acid ("GABA") is one of the
major inhibitory transmitters in the central nervous system of
mammals. GABA is not transported efficiently into the brain from
the bloodstream (i.e., GABA does not effectively cross the
blood-brain barrier). Consequently, brain cells provide virtually
all of the GABA found in the brain (GABA is biosynthesized by
decarboxylation of glutamic acid with pyridoxal phosphate).
[0004] GABA regulates neuronal excitability through binding to
specific membrane proteins (i.e., GABAA receptors), which results
in opening of an ion channel. The entry of chloride ion through the
ion channel leads to hyperpolarization of the recipient cell, which
consequently prevents transmission of nerve impulses to other
cells. Low levels of GABA have been observed in individuals
suffering from epileptic seizures, motion disorders (e.g., multiple
sclerosis, action tremors, tardive dyskinesia), panic, anxiety,
depression, alcoholism and manic behavior.
[0005] The implication of low GABA levels in a number of common
disease states and/or common medical disorders has stimulated
intensive interest in preparing GABA analogs, which have superior
pharmaceutical properties in comparison to GABA (e.g., the ability
to cross the blood brain barrier). Accordingly, a number of GABA
analogs, with considerable pharmaceutical activity have been
synthesized in the art (See, e.g., Satzinger et al., U.S. Pat. No.
4,024,175; Silverman et al., U.S. Pat. No. 5,563,175; Horwell et
al., U.S. Pat. No. 6,020,370; Silverman et al., U.S. Pat. No.
6,028,214; Horwell et al., U.S. Pat. No. 6,103,932; Silverman et
al., U.S. Pat. No. 6,117,906; Silverman, International Publication
No. WO 92/09560; Silverman et al., International Publication No. WO
93/23383; Horwell et al., International Publication No. WO
97/29101, Horwell et al., International Publication No. WO
97/33858; Horwell et al., International Publication No. WO
97/33859; Bryans et al., International Publication No. WO 98/17627;
Guglietta et al., International Publication No. WO 99/08671; Bryans
et al., International Publication No. WO 99/21824; Bryans et al.,
International Publication No. WO 99/31057; Belliotti et al.,
International Publication No. WO 99/31074; Bryans et al.,
International Publication No. WO 99/31075; Bryans et al.,
International Publication No. WO 99/61424; Bryans et al.,
International Publication No. WO 00/15611; Bryans, International
Publication No. WO 00/31020; Bryans et al., International
Publication No. WO 00/50027; and Bryans et al., International
Publication No. WO 02/00209).
##STR00001##
[0006] Pharmaceutically important GABA analogs include, for
example, gabapentin (1), pregabalin (2), vigabatrin (3), and
baclofen (4) shown above. Gabapentin is a lipophilic GABA analog
that can pass through the blood-brain barrier, which has been used
to clinically treat epilepsy since 1994. Gabapentin also has
potentially useful therapeutic effects in chronic pain states
(e.g., neuropathic pain, muscular and skeletal pain), psychiatric
disorders (e.g., panic, anxiety, depression, alcoholism and manic
behavior), movement disorders (e.g., multiple sclerosis, action
tremors, tardive dyskinesia), etc. (Magnus, Epilepsia, 1999,
40:S66-S72). Currently, gabapentin is also used in the clinical
management of neuropathic pain. Pregabalin, which possesses greater
potency in pre-clinical models of pain and epilepsy than gabapentin
is presently in Phase III clinical trials.
[0007] A significant problem with many GABA analogs is
intramolecular reaction of the .gamma. amino group with the
carboxyl functionality to form the .gamma.-lactam, as exemplified
for gabapentin below. Formation of .gamma.-lactam (5) presents
serious difficulties in formulating gabapentin because of its
toxicity. For example, gabapentin has a toxicity (LD.sub.50, mouse)
of more than 8000 mg/kg, while the corresponding lactam (5) has a
toxicity (LD.sub.50, mouse) of 300 mg/kg. Consequently, formation
of side products such as lactams during synthesis of GABA analogs
and/or formulation and/or storage of GABA analogs or compositions
of GABA analogs must be minimized for safety reasons (particularly,
in the case of gabapentin).
##STR00002##
[0008] The problem of lactam contamination of GABA analogs,
particularly in the case of gabapentin, has been partially overcome
through use of special additional purification steps, precise
choice of adjuvant materials in pharmaceutical compositions and
careful control procedures (Augurt et al., U.S. Pat. No.
6,054,482). However, attempts to prevent lactam contamination have
not been entirely successful, in either synthesis or storage of
GABA analogs such as gabapentin or compositions thereof.
[0009] Rapid systemic clearance is another significant problem with
many GABA analogs including gabapentin, which consequently require
frequent dosing to maintain a therapeutic or prophylactic
concentration in the systemic circulation (Bryans et al., Med. Res.
Rev., 1999, 19, 149-177). For example, dosing regimens of 300-600
mg doses of gabapentin administered three times per day are
typically used for anticonvulsive therapy. Higher doses (1800-3600
mg/d in divided doses) are typically used for the treatment of
neuropathic pain states.
[0010] Sustained released formulations are a conventional solution
to the problem of rapid systemic clearance, as is well known to
those of skill in the art (See, e.g., "Remington's Pharmaceutical
Sciences," Philadelphia College of Pharmacy and Science, 17th
Edition, 1985). Osmotic delivery systems are also recognized
methods for sustained drug delivery (See, e.g., Verma et al., Drug
Dev. Ind. Pharm., 2000, 26:695-708). Many GABA analogs, including
gabapentin and pregabalin, are not absorbed via the large
intestine. Rather, these compounds are typically absorbed in the
small intestine by the large neutral amino acid transporter
("LNAA") (Jezyk et al., Pharm. Res., 1999, 16, 519-526). The rapid
passage of conventional dosage forms through the proximal
absorptive region of the gastrointestinal tract has prevented the
successful application of sustained release technologies to many
GABA analogs.
[0011] Thus, there is a significant need for effective sustained
release versions of GABA analogs to minimize increased dosing
frequency due to rapid systemic clearance of these compounds. There
is also a need for pure GABA analogs, (particularly gabapentin and
pregablin analogs) which are substantially pure and do not
spontaneously lactamize during either formulation or storage.
2. SUMMARY OF THE INVENTION
[0012] The present invention addresses these and other needs by
providing prodrugs of GABA analogs, pharmaceutical compositions of
prodrugs of GABA analogs and methods for making prodrugs of GABA
analogs. The present invention also provides methods for using
prodrugs of GABA analogs, and methods for using pharmaceutical
compositions of prodrugs of GABA analogs for treating or preventing
common diseases and/or disorders.
[0013] Importantly, the prodrugs provided by the present invention
may possess significant pharmaceutical advantages of particular use
in medicine. First, the promoiety of the prodrugs of GABA analogs
provided by the current invention are typically labile in vivo
(i.e., cleaved by either enzymatic or chemical means to generate
substantial quantities of a GABA analog before the prodrug is
cleared from a patient. Second, the promoiety derivative provided
by cleavage of the promoiety from the prodrug, and any metabolite
thereof, is typically non-toxic when administered to a mammal in
accordance with dosing regimens typically followed with the GABA
analog.
[0014] The compounds of the instant invention have a promoiety
attached to the .gamma. amino group of GABA analogs. This promoiety
may be directly attached to the .gamma. amino group of a GABA
analog, or optionally may be attached to the amino group of an
.alpha.-amino acid promoiety, or to the hydroxy group of an
.alpha.-hydroxy acid promoiety, which itself is attached to the
.gamma. amino group of the GABA analog.
[0015] The compounds of the invention may also have a promoiety
attached to the carboxyl group of GABA analogs. The carboxyl
promoiety will typically be an ester or thioester group. A wide
variety of ester or thioester groups may be used to form carboxyl
promoieties.
[0016] Accordingly, the compounds of the invention may include as
many as four promoieties, including one carboxyl promoiety and up
to three amino promoieties attached in sequence to the .gamma.
amino group (i.e., such that each promoiety is sequentially cleaved
from the N-terminal end of the GABA analog). The compounds of the
invention may contain two amino promoieties and one carboxyl
promoiety, two amino promoieties, one amino promoiety and one
carboxyl promoiety or one amino promoiety. Preferably, in those
compounds of the invention which contain both an amino promoiety
and a carboxyl promoiety, the carboxyl promoiety is hydrolyzed
prior to the complete cleavage of the promoiety (ies) attached to
the amine group.
[0017] In a first aspect, the present invention provides compounds
of Formula (I), Formula (II) or Formula (III):
##STR00003##
or a pharmaceutically acceptable salt, hydrate or solvate thereof,
wherein: m, n, t and u are independently 0 or 1;
X is O or NR.sup.16;
W is O or NR.sup.17;
Y is O or S;
[0018] R.sup.1 is selected from the group consisting of hydrogen,
R.sup.24C(O)--, R.sup.25OC(O)--, R.sup.24C(S)--, R.sup.25OC(S)--,
R.sup.25SC(O)--, R.sup.25SC(S)--, (R.sup.9O)(R.sup.10O)P(O)--,
R.sup.25S--,
##STR00004##
each R.sup.2 is independently selected from the group consisting of
hydrogen, alkyl, substituted alkyl, alkoxy, substituted alkoxy,
acyl, substituted acyl, acylamino, substituted acylamino,
alkylamino, substituted alkylamino, alklysulfinyl, substituted
alkylsulfinyl, alkylsulfonyl, substituted alkylsulfonyl, alkylthio,
substituted alkylthio, alkoxycarbonyl, substituted alkoxycarbonyl,
aryl, substituted aryl, arylalkyl, substituted arylalkyl, aryloxy,
substituted aryloxy, carbamoyl, cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl, dialkylamino,
substituted dialkylamino, halo, heteroalkyl, substituted
heteroalkyl, heteroaryl, substituted heteroaryl, heteroarylalkyl,
substituted heteroarylalkyl, heteroalkyloxy, substituted
heteroalkyloxy, heteroaryloxy and substituted heteroaryloxy, or
optionally, R.sup.2 and R.sup.16 together with the atoms to which
they are attached form a cycloheteroalkyl or substituted
cycloheteroalkyl ring; R.sup.3 and R.sup.6 are independently
selected from the group consisting of hydrogen, alkyl, substituted
alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl,
cycloalkyl, substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl; R.sup.4 and
R.sup.5 are independently selected from the group consisting of
hydrogen, alkyl, substituted alkyl, acyl, substituted acyl,
arylalkyl, substituted arylalkyl, cycloalkyl, substituted
cycloalkyl, cycloheteroalkyl, substituted cycloheteroalkyl,
heteroarylalkyl and substituted heteroarylalkyl or optionally,
R.sup.4 and R.sup.5 together with the carbon atom to which they are
attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl or bridged
cycloalkyl ring; R.sup.8 and R.sup.12 are independently selected
from the group consisting of hydrogen, acyl, substituted acyl,
alkoxycarbonyl, substituted alkoxycarbonyl, alkyl, substituted
alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl,
cycloalkyl, substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl and substituted
heteroarylalkyl, or optionally R.sup.8 and R.sup.12 together with
the carbon atoms to which they are attached form a cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring; R.sup.11 is selected from the group
consisting of hydrogen, alkyl, substituted alkyl, acyl, substituted
acyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl,
carbamoyl, cyano, cycloalkyl, substituted cycloalkyl,
heterocycloalkyl, substituted heterocycloalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl, substituted
heteroarylalkyl, alkoxycarbonyl, substituted alkoxycarbonyl,
cycloheteroalkyloxycarbonyl, substituted
cycloheteroalkyloxycarbonyl, aryloxycarbonyl, substituted
aryloxycarbonyl, heteroaryloxycarbonyl, substituted
heteroaryloxycarbonyl and nitro; R.sup.7, R.sup.9, R.sup.10,
R.sup.15, R.sup.16 and R.sup.17 are independently selected from the
group consisting of hydrogen, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl and substituted
heteroarylalkyl; R.sup.13 and R.sup.14 are independently selected
from the group consisting of hydrogen, alkyl, substituted alkyl,
alkoxycarbonyl, substituted alkoxycarbonyl, aryl, substituted aryl,
arylalkyl, substituted arylalkyl, carbamoyl, cycloalkyl,
substituted cycloalkyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl or optionally,
R.sup.13 and R.sup.14 together with the carbon atom to which they
are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring; R.sup.20 and
R.sup.21 are independently selected from the group consisting of
hydrogen, acyl, substituted acyl, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl and substituted
heteroarylalkyl or optionally R.sup.20 and R.sup.21 together with
the carbon atom to which they are attached form a cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring; R.sup.22 and R.sup.23 are independently
selected from the group consisting of hydrogen, alkyl, substituted
alkyl, aryl, substituted aryl, arylalkyl and substituted arylalkyl
or optionally, R.sup.22 and R.sup.23 together with the carbon atom
to which they are attached form a cycloalkyl, substituted
cycloalkyl, cycloheteroalkyl or substituted cycloheteroalkyl ring;
R.sup.24 is selected from the group consisting of hydrogen, acyl,
substituted acyl, alkyl, substituted alkyl, aryl, substituted aryl,
arylalkyl, substituted arylalkyl, cycloalkyl, substituted
cycloalkyl, cycloheteroalkyl, substituted cycloheteroalkyl,
heteroalkyl, substituted heteroalkyl, heteroaryl, substituted
heteroaryl, heteroarylalkyl and substituted heteroarylalkyl; and
R.sup.25 is selected from the group consisting of acyl, substituted
acyl, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,
substituted arylalkyl, cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl, heteroalkyl,
substituted heteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl.
[0019] In a second aspect, the present invention provides
pharmaceutical compositions of compounds of the invention. The
pharmaceutical compositions generally comprise one or more
compounds of the invention, and a pharmaceutically acceptable
vehicle.
[0020] In a third aspect, the present invention provides methods
for treating or preventing epilepsy, depression, anxiety,
psychosis, faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain (especially, neuropathic
pain and muscular and skeletal pain), inflammatory disease (i.e.,
arthritis), insomnia, gastrointestinal disorders or ethanol
withdrawal syndrome. The methods generally involve administering to
a patient in need of such treatment or prevention a therapeutically
effective amount of a compound of the invention.
[0021] In a fourth aspect, the current invention provides
pharmaceutical compositions for treating or preventing epilepsy,
depression, anxiety, psychosis, faintness attacks, hypokinesia,
cranial disorders, neurodegenerative disorders, panic, pain
(especially, neuropathic pain and muscular and skeletal pain),
inflammatory disease (i.e., arthritis), insomnia, gastrointestinal
disorders or ethanol withdrawal syndrome in a patient in need of
such treatment or prevention. The methods generally involve
administering to a patient in need of such treatment or prevention
a therapeutically effective amount of a pharmaceutical composition
of the invention.
[0022] In a fifth aspect, the invention comprises a GABA analog
derivative compound, M-G, for administration to a patient in need
of therapy, wherein M is a promoiety and G is derived from a GABA
analog, H-G (where H is hydrogen). The promoiety M, once cleaved
from G, and any metabolite thereof, exhibits a carcinogenically
toxic dose (TD.sub.50) in rats of greater than 0.2 mmol/kg/day.
Further, the promoiety M cleaves from G at a sufficient rate in
vivo, upon colonic administration to rats, to produce: [0023] (i) a
maximum concentration of H-G in plasma (C.sub.max) of at least 120%
of the C.sub.max of H-G in plasma is achieved by colonically
administering an equimolar dose of H-G; and [0024] (ii) an AUC that
is at least 120% of the AUC is achieved by colonically
administering an equimolar dose of H-G.
[0025] Preferably, M-G is a derivative of Formula (XIV):
##STR00005##
or a pharmaceutically acceptable salt, hydrate or solvate thereof,
wherein: R is hydrogen or R and R.sup.6 together with the atoms to
which they are attached form an azetidine, substituted azetidine,
pyrrolidine or substituted pyrrolidine ring; and Y, R.sup.3,
R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are as previously
defined.
[0026] Most preferably, M is a derivative of Formula (XV):
##STR00006##
[0027] wherein:
[0028] n, X, R.sup.1 and R.sup.2 are as previously defined.
3. DETAILED DESCRIPTION OF THE INVENTION
3.1 Definitions
[0029] "Active transport or active transport process" refers to the
movement of molecules across cellular membranes that:
[0030] a) is directly or indirectly dependent on an energy mediated
process (i.e., driven by ATP hydrolysis, ion gradient, etc.);
or
[0031] b) occurs by facilitated diffusion mediated by interaction
with specific transporter proteins.
[0032] "Alkyl" refers to a saturated or unsaturated, branched,
straight-chain or cyclic monovalent hydrocarbon radical derived by
the removal of one hydrogen atom from a single carbon atom of a
parent alkane, alkene or alkyne. Typical alkyl groups include, but
are not limited to, methyl; ethyls such as ethanyl, ethenyl,
ethynyl; propyls such as propan-1-yl, propan-2-yl,
cyclopropan-1-yl, prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl
(allyl), cycloprop-1-en-1-yl; cycloprop-2-en-1-yl, prop-1-yn-1-yl,
prop-2-yn-1-yl, etc.; butyls such as butan-1-yl, butan-2-yl,
2-methyl-propan-1-yl, 2-methyl-propan-2-yl, cyclobutan-1-yl,
but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl,
but-2-en-1-yl, but-2-en-2-yl, buta-1,3-dien-1-yl,
buta-1,3-dien-2-yl, cyclobut-1-en-1-yl, cyclobut-1-en-3-yl,
cyclobuta-1,3-dien-1-yl, but-1-yn-1-yl, but-1-yn-3-yl,
but-3-yn-1-yl, etc.; and the like.
[0033] The term "alkyl" is specifically intended to include groups
having any degree or level of saturation, i.e., groups having
exclusively single carbon-carbon bonds, groups having one or more
double carbon-carbon bonds, groups having one or more triple
carbon-carbon bonds and groups having mixtures of single, double
and triple carbon-carbon bonds. Where a specific level of
saturation is intended, the expressions "alkanyl," "alkenyl," and
"alkynyl" are used. Preferably, an alkyl group comprises from 1 to
20 carbon atoms, more preferably, from 1 to 10 carbon atoms.
[0034] "Alkanyl" refers to a saturated branched, straight-chain or
cyclic alkyl radical derived by the removal of one hydrogen atom
from a single carbon atom of a parent alkane. Typical alkanyl
groups include, but are not limited to, methanyl; ethanyl;
propanyls such as propan-1-yl, propan-2-yl (isopropyl),
cyclopropan-1-yl, etc.; butanyls such as butan-1-yl, butan-2-yl
(sec-butyl), 2-methyl-propan-1-yl (isobutyl), 2-methyl-propan-2-yl
(t-butyl), cyclobutan-1-yl, etc.; and the like.
[0035] "Alkenyl" refers to an unsaturated branched, straight-chain
or cyclic alkyl radical having at least one carbon-carbon double
bond derived by the removal of one hydrogen atom from a single
carbon atom of a parent alkene. The group may be in either the cis
or trans conformation about the double bond(s). Typical alkenyl
groups include, but are not limited to, ethenyl; propenyls such as
prop-1-en-1-yl, prop-1-en-2-yl, prop-2-en-1-yl (allyl),
prop-2-en-2-yl, cycloprop-1-en-1-yl; cycloprop-2-en-1-yl; butenyls
such as but-1-en-1-yl, but-1-en-2-yl, 2-methyl-prop-1-en-1-yl,
but-2-en-1-yl, but-2-en-1-yl, but-2-en-2-yl, buta-1,3-dien-1-yl,
buta-1,3-dien-2-yl, cyclobut-1-en-1-yl, cyclobut-1-en-3-yl,
cyclobuta-1,3-dien-1-yl, etc.; and the like.
[0036] "Alkynyl" refers to an unsaturated branched, straight-chain
or cyclic alkyl radical having at least one carbon-carbon triple
bond derived by the removal of one hydrogen atom from a single
carbon atom of a parent alkyne. Typical alkynyl groups include, but
are not limited to, ethynyl; propynyls such as prop-1-yn-1-yl,
prop-2-yn-1-yl, etc.; butynyls such as but-1-yn-1-yl,
but-1-yn-3-yl, but-3-yn-1-yl, etc.; and the like.
[0037] "Acyl" refers to a radical --C(O)R, where R is hydrogen,
alkyl, cycloalkyl, cycloheteroalkyl, aryl, arylalkyl, heteroalkyl,
heteroaryl, heteroarylalkyl as defined herein. Representative
examples include, but are not limited to formyl, acetyl,
cylcohexylcarbonyl, cyclohexylmethylcarbonyl, benzoyl,
benzylcarbonyl and the like.
[0038] "Acylamino" (or alternatively "acylamido") refers to a
radical --NR'C(O)R, where R' and R are each independently hydrogen,
alkyl, cycloalkyl, cycloheteroalkyl, aryl, arylalkyl, heteroalkyl,
heteroaryl, heteroarylalkyl, as defined herein. Representative
examples include, but are not limited to, formylamino, acetylamino
(i.e., acetamido), cyclohexylcarbonylamino,
cyclohexylmethyl-carbonylamino, benzoylamino (i.e., benzamido),
benzylcarbonylamino and the like.
[0039] "Acyloxy" refers to a radical --OC(O)R, where R is hydrogen,
alkyl, cycloalkyl, cycloheteroalkyl, aryl, arylalkyl, heteroalkyl,
heteroaryl or heteroarylalkyl, as defined herein.
[0040] Representative examples include, but are not limited to,
acetyloxy (or acetoxy), butyloxy (or butoxy), benzoyloxy and the
like.
[0041] "Alkylamino" means a radical --NHR where R represents an
alkyl or cycloalkyl group as defined herein. Representative
examples include, but are not limited to, methylamino, ethylamino,
1-methylethylamino, cyclohexyl amino and the like.
[0042] "Alkoxy" refers to a radical --OR where R represents an
alkyl or cycloalkyl group as defined herein. Representative
examples include, but are not limited to, methoxy, ethoxy, propoxy,
butoxy, cyclohexyloxy and the like.
[0043] "Alkoxycarbonyl" refers to a radical --C(O)-alkoxy where
alkoxy is as defined herein.
[0044] "Alkylsulfonyl" refers to a radical --S(O).sub.2R where R is
an alkyl or cycloalkyl group as defined herein. Representative
examples include, but are not limited to, methylsulfonyl,
ethylsulfonyl, propylsulfonyl, butylsulfonyl and the like.
[0045] "Alkylsulfinyl" refers to a radical --S(O)R where R is an
alkyl or cycloalkyl group as defined herein. Representative
examples include, but are not limited to, methylsulfinyl,
ethylsulfinyl, propylsulfinyl, butylsulfinyl and the like.
[0046] "Alkylthio" refers to a radical --SR where R is an alkyl or
cycloalkyl group as defined herein that may be optionally
substituted as defined herein. Representative examples include, but
are not limited to methylthio, ethylthio, propylthio, butylthio and
the like.
[0047] "Amino" refers to the radical --NH.sub.2.
[0048] "Aryl" refers to a monovalent aromatic hydrocarbon group
derived by the removal of one hydrogen atom from a single carbon
atom of a parent aromatic ring system. Typical aryl groups include,
but are not limited to, groups derived from aceanthrylene,
acenaphthylene, acephenanthrylene, anthracene, azulene, benzene,
chrysene, coronene, fluoranthene, fluorene, hexacene, hexaphene,
hexalene, as-indacene, s-indacene, indane, indene, naphthalene,
octacene, octaphene, octalene, ovalene, penta-2,4-diene, pentacene,
pentalene, pentaphene, perylene, phenalene, phenanthrene, picene,
pleiadene, pyrene, pyranthrene, rubicene, triphenylene,
trinaphthalene and the like. Preferably, an aryl group comprises
from 6 to 20 carbon atoms, more preferably between 6 to 12 carbon
atoms.
[0049] "Arylalkyl" refers to an acyclic alkyl group in which one of
the hydrogen atoms bonded to a carbon atom, typically a terminal or
sp.sup.3 carbon atom, is replaced with an aryl group. Typical
arylalkyl groups include, but are not limited to, benzyl,
2-phenylethan-1-yl, 2-phenylethen-1-yl, naphthylmethyl,
2-naphthylethan-1-yl, 2-naphthylethen-1-yl, naphthobenzyl,
2-naphthophenylethan-1-yl and the like. Where specific alkyl
moieties are intended, the nomenclature arylalkanyl, arylalkenyl
and/or arylalkynyl is used. Preferably, an arylalkyl group is
(C.sub.6-C.sub.30) arylalkyl, e.g., the alkanyl, alkenyl or alkynyl
moiety of the arylalkyl group is (C.sub.1-C.sub.10) and the aryl
moiety is (C.sub.6-C.sub.20), more preferably, an arylalkyl group
is (C.sub.6-C.sub.20) arylalkyl, e.g., the alkanyl, alkenyl or
alkynyl moiety of the arylalkyl group is (C.sub.1-C.sub.8) and the
aryl moiety is (C.sub.6-C.sub.12).
[0050] "Arylalkyloxy" refers to an --O-arylalkyl group where
arylalkyl is as defined herein.
[0051] "Aryloxycarbonyl" refers to a radical --C(O)--O-aryl where
aryl is as defined herein.
[0052] "AUC" is the area under the plasma drug
concentration-versus-time curve extrapolated from zero time to
infinity.
[0053] "Bridged cycloalkyl" refers to a radical selected from the
group consisting of
##STR00007##
[0054] wherein:
[0055] A is (CR.sup.35R.sup.36).sub.b;
[0056] R.sup.35 and R.sup.36 are independently selected from the
group consisting of hydrogen and methyl;
[0057] R.sup.33 and R.sup.34 are independently selected from the
group consisting of hydrogen and methyl;
[0058] b is an integer from 1 to 4; and
[0059] c is an integer from 0 to 2.
[0060] "Carbamoyl" refers to the radical --C(O)N(R).sub.2 where
each R group is independently hydrogen, alkyl, cycloalkyl or aryl
as defined herein, which may be optionally substituted, as defined
herein.
[0061] "Carboxy" means the radical --C(O)OH.
[0062] "Carcinogenic potency (TD.sub.50)" (see Peto et al.,
Environmental Health Perspectives 1984, 58, 1-8) is defined for a
particular compound in a given animal species as that chronic
dose-rate in mg/kg body wt/day which would induce tumors in half
the test animals at the end of a standard lifespan for the species.
Since the tumor(s) of interest often does occur in control animals,
TD.sub.50 is more precisely defined as: that dose-rate in mg/kg
body wt/day which, if administered chronically for the standard
lifespan of the species, will halve the probability of remaining
tumorless throughout that period. A TD.sub.50 can be computed for
any particular type of neoplasm, for any particular tissue, or for
any combination of these.
[0063] "C.sub.max" is the highest drug concentration observed in
plasma following an extravascular dose of drug.
[0064] "Compounds of the invention" refers to compounds encompassed
by generic formulae disclosed herein and includes any specific
compounds within that formula whose structure is disclosed herein.
The compounds of the invention may be identified either by their
chemical structure and/or chemical name. When the chemical
structure and chemical name conflict, the chemical structure is
determinative of the identity of the compound. The compounds of the
invention may contain one or more chiral centers and/or double
bonds and therefore, may exist as stereoisomers, such as
double-bond isomers (i.e., geometric isomers), enantiomers or
diastereomers. Accordingly, the chemical structures depicted herein
encompass all possible enantiomers and stereoisomers of the
illustrated compounds including the stereoisomerically pure form
(e.g., geometrically pure, enantiomerically pure or
diastereomerically pure) and enantiomeric and stereoisomeric
mixtures. Enantiomeric and stereoisomeric mixtures can be resolved
into their component enantiomers or stereoisomers using separation
techniques or chiral synthesis techniques well known to the skilled
artisan. The compounds of the invention may also exist in several
tautomeric forms including the enol form, the keto form and
mixtures thereof. Accordingly, the chemical structures depicted
herein encompass all possible tautomeric forms of the illustrated
compounds. The compounds of the invention also include isotopically
labeled compounds where one or more atoms have an atomic mass
different from the atomic mass conventionally found in nature.
Examples of isotopes that may be incorporated into the compounds of
the invention include, but are not limited to, .sup.2H, .sup.3H,
.sup.13C, .sup.14C, .sup.15N, .sup.18O, .sup.17O, .sup.31P,
.sup.32P, .sup.3S, .sup.18F and .sup.36Cl. Further, it should be
understood, when partial structures of the compounds of the
invention are illustrated, that brackets indicate the point of
attachment of the partial structure to the rest of the
molecule.
[0065] "Composition of the invention" refers to at least one
compound of the invention and a pharmaceutically acceptable
vehicle, with which the compound is administered to a patient.
[0066] When administered to a patient, the compounds of the
invention are administered in isolated form, which means separated
from a synthetic organic reaction mixture.
[0067] "Cyano" means the radical --CN.
[0068] "Cycloalkyl" refers to a saturated or unsaturated cyclic
alkyl radical. Where a specific level of saturation is intended,
the nomenclature "cycloalkanyl" or "cycloalkenyl" is used. Typical
cycloalkyl groups include, but are not limited to, groups derived
from cyclopropane, cyclobutane, cyclopentane, cyclohexane, and the
like. Preferably, the cycloalkyl group is (C.sub.3-C.sub.10)
cycloalkyl, more preferably (C.sub.3-C.sub.7) cycloalkyl.
[0069] "Cycloheteroalkyl" refers to a saturated or unsaturated
cyclic alkyl radical in which one or more carbon atoms (and any
associated hydrogen atoms) are independently replaced with the same
or different heteroatom. Typical heteroatoms to replace the carbon
atom(s) include, but are not limited to, N, P, O, S, Si, etc. Where
a specific level of saturation is intended, the nomenclature
"cycloheteroalkanyl" or "cycloheteroalkenyl" is used. Typical
cycloheteroalkyl groups include, but are not limited to, groups
derived from epoxides, imidazolidine, morpholine, piperazine,
piperidine, pyrazolidine, pyrrolidine, quinuclidine, and the
like.
[0070] "Cycloheteroalkyloxycarbonyl" refers to a radical --C(O)--OR
where R is cycloheteroalkyl is as defined herein.
[0071] "Derived from a bile acid" refers to a moiety that is
structurally related to a compound of Formulae (XVII) or
(XVIII):
##STR00008##
[0072] wherein each of D, E and F are independently H or OH.
[0073] The structure of the moiety is identical to the compounds
above except at 1 or 2 positions. At these positions, a hydrogen
atom attached to a hydroxyl group and/or the hydroxyl moiety of the
carboxylic acid group has been replaced with a covalent bond that
serves as a point of attachment to another moiety, which is
preferably a GABA analog or GABA analog derivative.
[0074] "Derived from a GABA analog" refers to a moiety that is
structurally related to a GABA analog. The structure of the moiety
is identical to the compound except at 1 or 2 positions. At these
positions, a hydrogen atom attached to the amino group, and
(optionally) the hydroxyl moiety of the carboxylic acid group has
been replaced with a covalent bond that serves as a point of
attachment to another moiety.
[0075] "Dialkylamino" means a radical --NRR' where R and R'
independently represent an alkyl or cycloalkyl group as defined
herein. Representative examples include, but are not limited to,
dimethylamino, methylethylamino, di-(1-methylethyl)amino,
(cyclohexyl)(methyl)amino, (cyclohexyl)(ethyl)amino,
(cyclohexyl)(propyl)amino and the like.
[0076] "GABA analog" refers to a compound, unless specified
otherwise, as having the following structure:
##STR00009##
[0077] wherein:
[0078] R is hydrogen, or R and R.sup.6 together with the atoms to
which they are attached form an azetidine, substituted azetidine,
pyrrolidine or substituted pyrrolidine ring;
[0079] R.sup.3 and R.sup.6 are independently selected from the
group consisting of hydrogen, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl; and
[0080] R.sup.4 and R.sup.5 are independently selected from the
group consisting of hydrogen, alkyl, substituted alkyl, acyl,
substituted acyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,
substituted cycloheteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl or optionally,
R.sup.4 and R.sup.5 together with the carbon atom to which they are
attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl or bridged
cycloalkyl ring.
[0081] "Halo" means fluoro, chloro, bromo, or iodo.
[0082] "Heteroalkyloxy" means an --O-heteroalkyl group where
heteroalkyl is as defined herein.
[0083] "Heteroalkyl. Heteroalkanyl, Heteroalkenyl, Heteroalkynyl"
refer to alkyl, alkanyl, alkenyl and alkynyl radical, respectively,
in which one or more of the carbon atoms (and any associated
hydrogen atoms) are each independently replaced with the same or
different heteroatomic groups. Typical heteroatomic groups include,
but are not limited to, --O--, --S--, --O--O--, --S--S--, --O--S--,
--NR'--, .dbd.N--N.dbd., --N.dbd.N--, --N.dbd.N--NR'--, --PH--,
--P(O).sub.2--, --O--P(O).sub.2--, --S(O)--, --S(O).sub.2--,
--SnH.sub.2-- and the like, where R' is hydrogen, alkyl,
substituted alkyl, cycloalkyl, substituted cycloalkyl, aryl or
substituted aryl.
[0084] "Heteroaryl" refers to a monovalent heteroaromatic radical
derived by the removal of one hydrogen atom from a single atom of a
parent heteroaromatic ring system. Typical heteroaryl groups
include, but are not limited to, groups derived from acridine,
arsindole, carbazole, .beta.-carboline, chromane, chromene,
cinnoline, furan, imidazole, indazole, indole, indoline,
indolizine, isobenzofuran, isochromene, isoindole, isoindoline,
isoquinoline, isothiazole, isoxazole, naphthyridine, oxadiazole,
oxazole, perimidine, phenanthridine, phenanthroline, phenazine,
phthalazine, pteridine, purine, pyran, pyrazine, pyrazole,
pyridazine, pyridine, pyrimidine, pyrrole, pyrrolizine,
quinazoline, quinoline, quinolizine, quinoxaline, tetrazole,
thiadiazole, thiazole, thiophene, triazole, xanthene, and the like.
Preferably, the heteroaryl group is between 5-20 membered
heteroaryl, more preferably between 5-10 membered heteroaryl.
Preferred heteroaryl groups are those derived from thiophene,
pyrrole, benzothiophene, benzofuran, indole, pyridine, quinoline,
imidazole, oxazole and pyrazine.
[0085] "Heteroaryloxycarbonyl" refers to a radical --C(O)--OR where
R is heteroaryl as defined herein.
[0086] "Heteroarylalkyl" refers to an acyclic alkyl group in which
one of the hydrogen atoms bonded to a carbon atom, typically a
terminal or sp.sup.3 carbon atom, is replaced with a heteroaryl
group. Where specific alkyl moieties are intended, the nomenclature
heteroarylalkanyl, heteroarylalkenyl and/or heterorylalkynyl is
used. In preferred embodiments, the heteroarylalkyl group is a 6-30
membered heteroarylalkyl, e.g., the alkanyl, alkenyl or alkynyl
moiety of the heteroarylalkyl is 1-10 membered and the heteroaryl
moiety is a 5-20-membered heteroaryl, more preferably, 6-20
membered heteroarylalkyl, e.g., the alkanyl, alkenyl or alkynyl
moiety of the heteroarylalkyl is 1-8 membered and the heteroaryl
moiety is a 5-12-membered heteroaryl.
[0087] "Passive diffusion" refers to uptake of an agent that is not
mediated by a specific transporter protein. An agent that is
substantially incapable of passive diffusion has a permeability
across a standard cell monolayer (e.g., Caco-2) in vitro of less
than 5.times.10.sup.-6 cm/sec, and usually less than
1.times.10.sup.-6 cm/sec (in the absence of an efflux
mechanism).
[0088] "Pharmaceutically acceptable" means approved or approvable
by a regulatory agency of the Federal or a state government or
listed in the U.S. Pharmacopoeia or other generally recognized
pharmacopoeia for use in animals, and more particularly in
humans.
[0089] "Pharmaceutically acceptable salt" refers to a salt of a
compound of the invention, which is pharmaceutically acceptable and
possesses the desired pharmacological activity of the parent
compound. Such salts include: (1) acid addition salts, formed with
inorganic acids such as hydrochloric acid, hydrobromic acid,
sulfuric acid, nitric acid, phosphoric acid, and the like; or
formed with organic acids such as acetic acid, propionic acid,
hexanoic acid, cyclopentanepropionic acid, glycolic acid, pyruvic
acid, lactic acid, malonic acid, succinic acid, malic acid, maleic
acid, fumaric acid, tartaric acid, citric acid, benzoic acid,
3-(4-hydroxybenzoyl)benzoic acid, cinnamic acid, mandelic acid,
methanesulfonic acid, ethanesulfonic acid, 1,2-ethane-disulfonic
acid, 2-hydroxyethanesulfonic acid, benzenesulfonic acid,
4-chlorobenzenesulfonic acid, 2-naphthalenesulfonic acid,
4-toluenesulfonic acid, camphorsulfonic acid,
4-methylbicyclo[2.2.2]-oct-2-ene-1-carboxylic acid, glucoheptonic
acid, 3-phenylpropionic acid, trimethylacetic acid, tertiary
butylacetic acid, lauryl sulfuric acid, gluconic acid, glutamic
acid, hydroxynaphthoic acid, salicylic acid, stearic acid, muconic
acid, and the like; or (2) salts formed when an acidic proton
present in the parent compound is replaced by a metal ion, e.g., an
alkali metal ion, an alkaline earth ion, or an aluminum ion; or
coordinates with an organic base such as ethanolamine,
diethanolamine, triethanolamine, N-methylglucamine and the
like.
[0090] "Pharmaceutically acceptable vehicle" refers to a diluent,
adjuvant, excipient or carrier with which a compound of the
invention is administered.
[0091] "Patient" includes humans. The terms "human" and "patient"
are used interchangeably herein.
[0092] "Preventing" or "prevention" refers to a reduction in risk
of acquiring a disease or disorder (i.e., causing at least one of
the clinical symptoms of the disease not to develop in a patient
that may be exposed to or predisposed to the disease but does not
yet experience or display symptoms of the disease).
[0093] "Prodrug" refers to a derivative of a drug molecule that
requires a transformation within the body to release the active
drug. Prodrugs are frequently (though not necessarily)
pharmacologically inactive until converted to the parent drug.
[0094] "Promoiety" refers to a form of protecting group that when
used to mask a functional group within a drug molecule converts the
drug into a prodrug. Typically, the promoiety will be attached to
the drug via bond(s) that are cleaved by enzymatic or non-enzymatic
means in vivo.
[0095] "Protecting group" refers to a grouping of atoms that when
attached to a reactive functional group in a molecule masks,
reduces or prevents reactivity of the functional group.
[0096] Examples of protecting groups can be found in Green et al.,
"Protective Groups in Organic Chemistry", (Wiley, 2.sup.nd ed.
1991) and Harrison et al., "Compendium of Synthetic Organic
Methods", Vols. 1-8 (John Wiley and Sons, 1971-1996).
Representative amino protecting groups include, but are not limited
to, formyl, acetyl, trifluoroacetyl, benzyl, benzyloxycarbonyl
("CBZ"), tert-butoxycarbonyl ("Boc"), trimethylsilyl ("TMS"),
2-trimethylsilyl-ethanesulfonyl ("SES"), trityl and substituted
trityl groups, allyloxycarbonyl, 9-fluorenylmethyloxycarbonyl
("FMOC"), nitro-veratryloxycarbonyl ("NVOC") and the like.
Representative hydroxy protecting groups include, but are not
limited to, those where the hydroxy group is either acylated or
alkylated such as benzyl, and trityl ethers as well as alkyl
ethers, tetrahydropyranyl ethers, trialkylsilyl ethers and allyl
ethers.
[0097] "Substituted" refers to a group in which one or more
hydrogen atoms are each independently replaced with the same or
different substituent(s). Typical substituents include, but are not
limited to, --X, --R.sup.29, --O, .dbd.O, --OR.sup.29, --SR.sup.29,
--S.sup.-, .dbd.S, --NR.sup.29R.sup.30, .dbd.NR.sup.29, --CX.sub.3,
--CF.sub.3, --CN, --OCN, --SCN, --NO, --NO.sub.2, .dbd.N.sub.2,
--N.sub.3, --S(O).sub.2O.sup.-, --S(O).sub.2OH,
--S(O).sub.2R.sup.29, --OS(O.sub.2)O.sup.-, --OS(O).sub.2R.sup.29,
--P(OX)(O.sup.-).sub.2, --P(O)(OR.sup.29)(O.sup.-),
--OP(O)(OR.sup.29)(OR.sup.30), --C(O)R.sup.29, --C(S)R.sup.29,
--C(O)OR.sup.29, --C(O)NR.sup.29R.sup.30, --C(O)O.sup.-,
--C(S)OR.sup.29, --NR.sup.31C(O)NR.sup.29R.sup.30,
--NR.sup.31C(S)NR.sup.29R.sup.30,
--NR.sup.31C(NR.sup.29)NR.sup.29R.sup.30 and
--C(NR.sup.29)NR.sup.29R.sup.30, where each X is independently a
halogen; each R.sup.29 and R.sup.30 are independently hydrogen,
alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,
substituted arylalkyl, cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl, heteroalkyl,
substituted heteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl, substituted heteroarylalkyl, --NR.sup.31R.sup.32,
--C(O)R.sup.31 or --S(O).sub.2R.sup.31 or optionally R.sup.29 and
R.sup.30 together with the atom to which they are both attached
form a cycloheteroalkyl or substituted cycloheteroalkyl ring; and
R.sup.31 and R.sup.32 are independently hydrogen, alkyl,
substituted alkyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,
substituted cycloheteroalkyl, heteroalkyl, substituted heteroalkyl,
heteroaryl, substituted heteroaryl, heteroarylalkyl or substituted
heteroarylalkyl.
[0098] "Transporter protein" refers to a protein that has a direct
or indirect role in transporting a molecule into and/or through a
cell. For example, a transporter protein may be, but is not limited
to, solute carrier transporters, co-transporters, counter
transporters, uniporters, symporters, antiporters, pumps,
equilibrative transporters, concentrative transporters and other
proteins, which mediate active transport, energy-dependent
transport, facilitated diffusion, exchange mechanisms and specific
absorption mechanisms. Transporter proteins, may also be, but are
not limited to, membrane-bound proteins that recognize a substrate
and effect its entry into or exit from a cell by a carrier-mediated
transporter or by receptor-mediated transport. A transporter
protein, may also be, but is not limited to, an intracellularly
expressed protein that participates in trafficking of substrates
through or out of a cell. Transporter proteins, may also be, but
are not limited to, proteins or glycoproteins exposed on the
surface of a cell that do not directly transport a substrate but
bind to the substrate holding it in proximity to a receptor or
transporter protein that effects entry of the substrate into or
through the cell. Examples of carrier proteins include: the
intestinal and liver bile acid transporters, dipeptide
transporters, oligopeptide transporters, simple sugar transporters
(e.g., SGLT1), phosphate transporters, monocarboxcylic acid
transporters, P-glycoprotein transporters, organic anion
transporters (OAT), and organic cation transporters. Examples of
receptor-mediated transport proteins include: viral receptors,
immunoglobulin receptors, bacterial toxin receptors, plant lectin
receptors, bacterial adhesion receptors, vitamin transporters and
cytokine growth factor receptors.
[0099] "Treating" or "treatment" of any disease or disorder refers,
in one embodiment, to ameliorating the disease or disorder (i.e.,
arresting or reducing the development of the disease or at least
one of the clinical symptoms thereof). In another embodiment
"treating" or "treatment" refers to ameliorating at least one
physical parameter, which may not be discernible by the patient. In
yet another embodiment, "treating" or "treatment" refers to
inhibiting the disease or disorder, either physically, (e.g.,
stabilization of a discernible symptom), physiologically, (e.g.,
stabilization of a physical parameter), or both. In yet another
embodiment, "treating" or "treatment" refers to delaying the onset
of the disease or disorder.
[0100] "Theraveuticallv effective amount" means the amount of a
compound that, when administered to a patient for treating a
disease, is sufficient to effect such treatment for the disease.
The "therapeutically effective amount" will vary depending on the
compound, the disease and its severity and the age, weight, etc.,
of the patient to be treated.
[0101] Reference will now be made in detail to preferred
embodiments of the invention. While the invention will be described
in conjunction with the preferred embodiments, it will be
understood that it is not intended to limit the invention to those
preferred embodiments. To the contrary, it is intended to cover
alternatives, modifications, and equivalents as may be included
within the spirit and scope of the invention as defined by the
appended claims.
3.2 The Compounds of the Invention
[0102] Those of skill in the art will appreciate that compounds of
Formulae (I), (II) and (III) share certain structural features in
common. These compounds are all GABA analogs (i.e.,
.gamma.-aminobutryic acid derivatives) to which promoieties have
been attached. In particular, R.sup.2, R.sup.3, R.sup.4, R.sup.5,
R.sup.6, X and Y are common substituents found in compounds of
Formulae (I), (II) and (III).
[0103] The compounds of the invention include compounds of Formula
(I), Formula (II) or Formula (III):
##STR00010##
[0104] or a pharmaceutically acceptable salt, hydrate or solvate
thereof, wherein: n, t, u, X, Y, R.sup.1, R.sup.2, R.sup.3,
R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.20, R.sup.21, R.sup.22
and R.sup.23 are as previously defined above.
[0105] In a preferred embodiment, compounds of Formulae (I), (II)
and (III) do not include the following compounds:
[0106] when R.sup.3 and R.sup.6 are both hydrogen, then R.sup.4 and
R.sup.5 are not both hydrogen and are not both methyl;
[0107] in a compound of Formula (I) when either n is 0 or when n is
1 and X is NR.sup.16, then R.sup.1 is not hydrogen;
[0108] in a compound of Formula (I) neither R.sup.1, R.sup.7O--,
R.sup.24C(O)--, R.sup.25C(O)-- nor R.sup.25O-- is a moiety derived
from a bile acid;
[0109] in a compound of Formula (I) when R.sup.1 is R.sup.24C(O)--
and n is 0, then R.sup.24 is not methyl, tert-butyl, 2-aminoethyl,
3-aminopropyl, benzyl, phenyl or 2-(benzoyloxymethyl)phenyl;
[0110] in a compound of Formula (I) when R.sup.1 is
R.sup.25OC(O)--, then R.sup.25 is not
R.sup.26C(O)CR.sup.13R.sup.14--, wherein R.sup.26 is selected from
the group consisting of hydrogen, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl and substituted
heteroarylalkyl;
[0111] in a compound of Formula (I) when R.sup.1 is R.sup.25OC(O)--
and n is 0, then R.sup.25 is not methyl, tert-butyl or benzyl;
[0112] in a compound of Formula (I) when n is 0 and R.sup.1 is
R.sup.25C(O)OCR.sup.13R.sup.14OC(O)-- then if either R.sup.13 or
R.sup.14 is hydrogen, alkoxycarbonyl, substituted alkoxycarbonyl,
carbamoyl, cycloalkoxycarbonyl or substituted cycloalkoxycarbonyl,
the other of R.sup.13 or R.sup.14 is not hydrogen;
[0113] in a compound of Formula (I) when n is 1, X is NH, R.sup.3,
R.sup.5 and R.sup.6 are each hydrogen, and R.sup.4 is cyclohexyl,
then R.sup.2 is not benzyl;
[0114] in a compound of Formula (II) when t is 1, u is 0, then
neither R.sup.20 nor R.sup.21 is 2-hydroxy-3-methyl-5-chlorophenyl;
and
[0115] in a compound of Formula (II) when u is 1 and X is O, then t
is 1.
[0116] In one embodiment of compounds of Formulae (I), (II) and
(III), when R.sup.3 and R.sup.6 are each hydrogen, then R.sup.4 and
R.sup.5 are neither both hydrogen nor both methyl.
[0117] In one embodiment of compounds of Formula (I), when either n
is 0 or when n is 1 and X is NR.sup.16, then R.sup.1 is not
hydrogen. In another embodiment, of compounds of Formula (I),
neither R.sup.1, R.sup.7O--, R.sup.24C(O)--, R.sup.25C(O)-- nor
R.sup.25O-- is a moiety derived from a bile acid. In still another
embodiment of compounds of Formula (I), when R.sup.1 is
R.sup.24C(O)-- and n is 0, then R.sup.24 is not alkyl, substituted
alkyl, arylalkyl, aryl or substituted aryl. In still another
embodiment of compounds of Formula (I), when R.sup.1 is
R.sup.24C(O)-- and n is 0, then R.sup.24 is not C.sub.1-4alkanyl,
benzyl, phenyl or substituted phenyl. In still another embodiment
of compounds of Formula (I), when R.sup.1 is R.sup.24C(O)-- and n
is 0, then R.sup.24 is not methyl, tert-butyl, 2-aminoethyl,
3-aminopropyl, benzyl, phenyl or 2-(benzoyloxymethyl)-phenyl. In
still another embodiment of compounds of Formula (I) when R.sup.1
is R.sup.25OC(O)--, then R.sup.25 is not
R.sup.26C(O)CR.sup.13R.sup.14--. In still another embodiment of
compounds of Formula (I) when R.sup.1 is R.sup.25OC(O)-- and n is
0, then R.sup.25 is not alkyl or arylalkyl. In still another
embodiment of compounds of Formula (I) when R.sup.1 is
R.sup.25OC(O)-- and n is 0, then R.sup.25 is not C.sub.1-4 alkanyl
or benzyl. In still another embodiment of compounds of Formula (I)
when R.sup.1 is R.sup.25OC(O)-- and n is 0, then R.sup.25 is not
methyl, tert-butyl or benzyl. In still another embodiment of
compounds of Formula (I) when n is 0 and R.sup.1 is
R.sup.25C(O)OCR.sup.13R.sup.14OC(O)-- then if either R.sup.13 or
R.sup.14 is hydrogen, alkoxycarbonyl, substituted alkoxycarbonyl,
carbamoyl, cycloalkoxycarbonyl or substituted cycloalkoxycarbonyl,
the other of R.sup.13 or R.sup.14 is not hydrogen. In still another
embodiment of compounds of Formula (I) when R.sup.3, R.sup.5 and
R.sup.6 are each hydrogen, then R.sup.4 is not cyclohexyl. In still
another embodiment of compounds of Formula (I) when n is 1, X is
NH, R.sup.3, R.sup.5, R.sup.6 are each hydrogen and R.sup.2 is
benzyl, then R.sup.4 is not cyclohexyl.
[0118] In one embodiment of compounds of Formula (II), neither
R.sup.20 nor R.sup.21 is 2-hydroxy-3-methyl-5-chlorophenyl. In one
embodiment of compounds of Formula (II), when u is 1 and X is O,
then t is 1.
[0119] In one embodiment of compounds of Formulae, (I) (II) and
(III), n is 0. In another embodiment, n is 1. When n is 1, and X is
NR.sup.16, preferably the .alpha.-amino acid is of the
L-stereochemical configuration.
[0120] In another embodiment of compounds of Formulae (I) and (II),
R.sup.7 is selected from the group consisting of hydrogen, alkyl,
substituted alkyl, aryl, substituted aryl, arylalkanyl, substituted
arylalkanyl, cycloalkanyl, substituted cycloalkanyl,
cycloheteroalkanyl and substituted cycloheteroalkanyl. In a
preferred embodiment, Y is O and R.sup.7 is hydrogen. In still
another embodiment, Y is O and R.sup.7 is alkanyl, substituted
alkanyl, alkenyl, substituted alkenyl, aryl or substituted aryl.
Preferably, R.sup.7 is methyl, ethyl, benzyl,
--C(CH.sub.3).dbd.CH.sub.2, --CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00011##
[0121] where V is O or CH.sub.2.
[0122] In one preferred embodiment of compounds of Formulae (I),
(II) and (III), R.sup.2 is selected from the group consisting of
hydrogen, alkyl, substituted alkyl, aryl, substituted aryl,
arylalkyl, substituted arylalkyl, cycloalkyl, substituted
cycloalkyl, cycloheteroalkyl, substituted cycloheteroalkyl,
heteroalkyl, substituted heteroalkyl, heteroaryl, substituted
heteroaryl, heteroarylalkyl and substituted heteroarylalkyl.
Preferably, R.sup.2 is selected from the group consisting hydrogen,
alkanyl, substituted alkanyl, aryl, substituted aryl, arylalkanyl,
substituted arylalkanyl, cycloalkanyl, heteroarylalkyl and
substituted heteroarylalkanyl.
[0123] In another embodiment compounds of Formulae (I), (II) and
(III), X is NH and R.sup.2 is hydrogen, cycloalkanyl or alkanyl.
Preferably, R.sup.2 is hydrogen, methyl, isopropyl, isobutyl,
sec-butyl, t-butyl, cyclopentyl or cyclohexyl. In another
embodiment, X is NH and R.sup.2 is substituted alkanyl. Preferably,
R.sup.2 is --CH.sub.2OH, --CH(OH)CH.sub.3, --CH.sub.2CO.sub.2H,
--CH.sub.2CH.sub.2CO.sub.2H, --CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2SCH.sub.3,
CH.sub.2SH, --CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. In still another
embodiment, X is NH and R.sup.2 is selected from the group
consisting of aryl, arylalkanyl, substituted arylalkanyl and
heteroarylalkanyl. Preferably, R.sup.2 is phenyl, benzyl,
4-hydroxybenzyl, 4-bromobenzyl, 2-imidazolyl or 2-indolyl. In yet
another embodiment, X is NR.sup.16 and R.sup.2 and R.sup.16
together with the atoms to which they are attached form a
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably
R.sup.2 and R.sup.16 together with the atoms to which they are
attached form an azetidine, pyrrolidine or piperidine ring.
[0124] In still another embodiment of compounds of Formulae (I),
(II) and (III), R.sup.3 is hydrogen. In still another embodiment,
R.sup.6 is hydrogen. In yet another embodiment, R.sup.3 and R.sup.6
are independently selected from the group consisting of hydrogen,
alkyl, substituted alkyl, aryl, substituted aryl, cycloalkyl and
substituted cycloalkyl. Preferably, R.sup.3 and R.sup.6 are
independently selected from the group consisting of hydrogen and
alkanyl. More preferably, R.sup.3 is hydrogen or alkanyl and
R.sup.6 is hydrogen.
[0125] In still another preferred embodiment of compounds of
Formulae (I), (II) and (III), R.sup.4 and R.sup.5 are independently
selected from the group consisting of hydrogen, alkyl, substituted
alkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl and
substituted cycloheteroalkyl. Preferably, R.sup.4 and R.sup.5 are
independently selected from the group consisting of hydrogen,
alkanyl and substituted alkanyl.
[0126] In another embodiment of compounds of Formulae (I), (II) and
(III), R.sup.4 and R.sup.5 together with the carbon atom to which
they are attached form a cycloalkanyl or substituted cycloalkanyl
ring. Preferably, R.sup.4 and R.sup.5 together with the carbon atom
to which they are attached form a cyclobutyl, substituted
cyclobutyl, cyclopentyl, substituted cyclopentyl, cyclohexyl or
substituted cyclohexyl ring. In another embodiment, R.sup.4 and
R.sup.5 together with the carbon atom to which they are attached
form a cycloheteroalkyl or substituted cycloheteroalkyl ring. In
still another embodiment, R.sup.4 and R.sup.5 together with the
carbon atom to which they are attached form a bridged cycloalkyl
ring.
[0127] In one embodiment of compounds of Formula (I), n is 1,
R.sup.1 is R.sup.24C(O)-- or R.sup.24C(S)-- and R.sup.24 is alkyl,
substituted alkyl, heteroalkyl, substituted heteroalkyl, aryl,
substituted aryl, heteroaryl or substituted heteroaryl. Preferably,
R.sup.24 is methyl, ethyl, 2-propyl, t-butyl,
--CH.sub.2OCH(CH.sub.3).sub.2, phenyl or 3-pyridyl.
[0128] In another embodiment of compounds of Formula (I), n is 1,
R.sup.1 is R.sup.25OC(O)-- or R.sup.25SC(O)-- and R.sup.25 is
alkyl, substituted alkyl, heteroalkyl, aryl, substituted aryl,
heteroaryl or substituted heteroaryl. Preferably, R.sup.25 is
ethyl, 2-propyl, neopentyl, --CH.sub.2OCH(CH.sub.3).sub.2, phenyl
or 2-pyridyl.
[0129] One preferred embodiment of compounds of Formula (I)
includes compounds of Formula (IV):
##STR00012##
[0130] or a pharmaceutically acceptable salt, hydrate or solvate
thereof, wherein: n, Y, R.sup.2, R.sup.3, R.sup.4, R.sup.5,
R.sup.6, R.sup.7, R.sup.13, R.sup.14, R.sup.16 and R.sup.25 are as
previously defined.
[0131] In a preferred embodiment, the compounds of Formula (IV), do
not include the following compounds:
[0132] when either R.sup.13 or R.sup.14 is hydrogen,
alkoxycarbonyl, substituted alkoxycarbonyl, carbamoyl,
cycloalkoxycarbonyl or substituted cycloalkoxycarbonyl, then the
other of R.sup.13 or R.sup.14 is not hydrogen; and
[0133] R.sup.25C(O) is not a moiety derived from a bile acid.
[0134] In one embodiment of compounds of Formulae (IV), R.sup.13
and R.sup.14 are independently hydrogen, alkyl, substituted alkyl,
alkoxycarbonyl, aryl, arylalkyl, carbamoyl, cycloalkyl, substituted
cycloalkyl, cycloalkoxycarbonyl or heteroaryl (preferably, when
R.sup.3 is alkoxycarbonyl, cycloalkoxycarbonyl or carbamoyl then
R.sup.14 is methyl). More preferably, R.sup.13 and R.sup.14 are
independently hydrogen, methyl, ethyl, propyl, isopropyl, butyl,
isobutyl, sec-butyl, tert-butyl, cyclopentyl, cyclohexyl,
methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl,
isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl,
sec-butoxycarbonyl, tert-butoxycarbonyl, cyclohexyloxycarbonyl,
phenyl, benzyl, phenethyl or 3-pyridyl.
[0135] In another embodiment of compounds of Formula (IV), R.sup.13
and R.sup.14 are independently hydrogen, alkanyl, substituted
alkanyl, cycloalkanyl or substituted cycloalkanyl. Preferably,
R.sup.13 and R.sup.14 are hydrogen, alkanyl or cycloalkanyl. More
preferably, R.sup.13 and R.sup.14 are independently hydrogen,
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
tert-butyl, cyclopentyl or cyclohexyl. Even more preferably,
R.sup.13 is methyl, ethyl, propyl, isopropyl, butyl, isobutyl,
sec-butyl, tert-butyl, cyclopentyl or cyclohexyl and R.sup.14 is
hydrogen, or R.sup.13 is methyl and R.sup.14 is methyl.
[0136] In still another embodiment of compounds of Formula (IV),
R.sup.13 and R.sup.14 are independently hydrogen, aryl, arylalkyl
or heteroaryl. More preferably, R.sup.13 and R.sup.14 are
independently hydrogen, phenyl, benzyl, phenethyl or 3-pyridyl.
Even more preferably, R.sup.13 is phenyl, benzyl, phenethyl or
3-pyridyl and R.sup.14 is hydrogen.
[0137] In still another embodiment of compounds of Formula (IV),
R.sup.13 and R.sup.14 are independently hydrogen, alkyl,
substituted alkyl, alkoxycarbonyl, carbamoyl, or
cycloalkoxycarbonyl. Preferably, when R.sup.13 is alkoxycarbonyl,
cycloalkoxycarbonyl or carbamoyl then R.sup.14 is methyl. More
preferably, R.sup.13 is methoxycarbonyl, ethoxycarbonyl,
isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl,
sec-butoxycarbonyl, tert-butoxycarbonyl or cyclohexyloxycarbonyl
and R.sup.14 is methyl.
[0138] In still another embodiment of compounds of Formula (IV),
R.sup.13 and R.sup.14 together with the carbon atom to which they
are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably,
R.sup.13 and R.sup.14 together with the carbon atom to which they
are attached form a cycloalkyl ring. More preferably, R.sup.13 and
R.sup.14 together with the carbon atom to which they are attached
form a cyclobutyl, cyclopentyl or cyclohexyl ring.
[0139] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl or substituted
heteroarylalkyl. Preferably, R.sup.25 is acyl, substituted acyl,
alkyl, substituted alkyl, aryl, arylalkyl, cycloalkyl or
heteroaryl. More preferably, R.sup.25 is methyl, ethyl, propyl,
isopropyl, butyl, isobutyl, sec-butyl, pentyl, isopentyl,
sec-pentyl, neopentyl, 1,1-dimethoxyethyl, 1,1-diethoxyethyl,
1-(1,3-dioxolan-2-yl)-ethyl, 1-(1,3-dioxan-2-yl)-ethyl,
1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl.
[0140] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl or substituted acyl. More preferably, R.sup.25 is
acetyl, propionyl, butyryl, benzoyl or phenacetyl.
[0141] In still another embodiment of compounds of Formula (IV),
R.sup.25 is alkanyl or substituted alkanyl. Preferably, R.sup.25 is
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl or
1-(1,3-dioxan-2-yl)-2-phenethyl. More preferably, R.sup.25 is
methyl, ethyl, propyl, isopropyl, butyl, 1,1-dimethoxyethyl or
1,1-diethoxyethyl.
[0142] In still another embodiment of compounds of Formula (IV),
R.sup.25 is aryl, arylalkyl or heteroaryl. Preferably, R.sup.25 is
phenyl, 4-methoxyphenyl, benzyl, phenethyl, styryl or
3-pyridyl.
[0143] In still another embodiment of compounds of Formula (IV),
R.sup.25 is cycloalkyl or substituted cycloalkyl. More preferably
R.sup.25 is cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl.
[0144] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl or substituted
heteroarylalkyl; and R.sup.13 and R.sup.14 are independently
hydrogen, alkyl, substituted alkyl, alkoxycarbonyl, substituted
alkoxycarbonyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, carbamoyl, cycloalkyl, substituted cycloalkyl,
cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl, heteroaryl or
substituted heteroaryl (preferably, when R.sup.13 is
alkoxycarbonyl, substituted alkoxycarbonyl, cycloalkoxycarbonyl,
substituted cycloalkoxycarbonyl or carbamoyl then R.sup.14 is
methyl). Preferably, R.sup.25 is acyl, substituted acyl, alkyl,
substituted alkyl, aryl, arylalkyl, cycloalkyl or heteroaryl and
R.sup.13 and R.sup.14 are independently hydrogen, alkyl,
substituted alkyl, alkoxycarbonyl, aryl, arylalkyl, carbamoyl,
cycloalkyl, cycloalkoxycarbonyl or heteroaryl (preferably, when
R.sup.13 is alkoxycarbonyl, substituted alkoxycarbonyl,
cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl or carbamoyl
then R.sup.14 is methyl). More preferably, R.sup.25 is methyl,
ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, pentyl,
isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl and R.sup.13 and
R.sup.14 are independently hydrogen, methyl, ethyl, propyl,
isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, cyclopentyl,
cyclohexyl, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl,
isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl,
sec-butoxycarbonyl, tert-butoxycarbonyl, cyclohexyloxycarbonyl,
phenyl, benzyl, phenethyl or 3-pyridyl. Even more preferably,
R.sup.25 is methyl, ethyl, propyl, isopropyl, butyl, isobutyl,
sec-butyl, 1,1-dimethoxyethyl, 1,1-diethoxyethyl,
1,1-dimethoxybenzyl, 1,1-diethoxybenzyl, 1,1-dimethoxy-2-phenethyl,
1,1-diethoxy-2-phenethyl, acetyl, propionyl, butyryl, benzoyl,
phenacetyl, phenyl, 4-methoxyphenyl, benzyl, phenethyl, cyclohexyl
or 3-pyridyl, and R.sup.13 and R.sup.14 are independently hydrogen,
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
tert-butyl, cyclopentyl, cyclohexyl, methoxycarbonyl,
ethoxycarbonyl, isopropoxycarbonyl, cyclohexyloxycarbonyl, phenyl,
benzyl, phenethyl or 3-pyridyl.
[0145] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl or substituted
heteroarylalkyl and R.sup.13 and R.sup.14 together with the atom to
which they are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably,
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
arylalkyl, cycloalkyl or heteroaryl and R.sup.13 and R.sup.14
together with the atom to which they are attached form a cycloalkyl
or substituted cycloalkyl ring. More preferably, R.sup.25 is
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl, and R.sup.13 and
R.sup.14 together with the atom to which they are attached form a
cyclobutyl, cyclopentyl or a cyclohexyl ring.
[0146] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl or substituted acyl and R.sup.13 and R.sup.14 are
independently hydrogen, alkyl, substituted alkyl, alkoxycarbonyl,
substituted alkoxycarbonyl, aryl, substituted aryl, arylalkyl,
substituted arylalkyl, carbamoyl, cycloalkyl, substituted
cycloalkyl, cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl,
heteroaryl or substituted heteroaryl (preferably, when R.sup.13 is
alkoxycarbonyl, substituted alkoxycarbonyl, cycloalkoxycarbonyl,
substituted cycloalkoxycarbonyl or carbamoyl then R.sup.14 is
methyl). Preferably, R.sup.25 is acetyl, propionyl, butyryl,
benzoyl or phenacetyl, and R.sup.13 and R.sup.14 are independently
hydrogen, alkyl, substituted alkyl, alkoxycarbonyl, substituted
alkoxycarbonyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, carbamoyl, cycloalkyl, substituted cycloalkyl,
cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl, heteroaryl or
substituted heteroaryl (preferably, when R.sup.13 is
alkoxycarbonyl, cycloalkoxycarbonyl or carbamoyl then R.sup.14 is
methyl).
[0147] In still another embodiment of compounds of Formula (IV),
R.sup.25 is alkanyl or substituted alkanyl and R.sup.13 and
R.sup.14 are independently hydrogen, alkyl, substituted alkyl,
alkoxycarbonyl, substituted alkoxycarbonyl, aryl, substituted aryl,
arylalkyl, substituted arylalkyl, carbamoyl, cycloalkyl,
substituted cycloalkyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl, heteroaryl or substituted heteroaryl
(preferably, when R.sup.13 is alkoxycarbonyl, substituted
alkoxycarbonyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl or carbamoyl then R.sup.14 is methyl).
Preferably, R.sup.25 is methyl, ethyl, propyl, isopropyl, butyl,
isobutyl, sec-butyl, pentyl, isopentyl, sec-pentyl, neopentyl,
1,1-dimethoxyethyl, 1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl or
1-(1,3-dioxan-2-yl)-2-phenethyl, and R.sup.13 and R.sup.14 are
independently hydrogen, alkyl, substituted alkyl, alkoxycarbonyl,
substituted alkoxycarbonyl, aryl, substituted aryl, arylalkyl,
substituted arylalkyl, carbamoyl, cycloalkyl, substituted
cycloalkyl, cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl,
heteroaryl or substituted heteroaryl (preferably, when R.sup.13 is
alkoxycarbonyl, cycloalkoxycarbonyl or carbamoyl then R.sup.14 is
methyl).
[0148] In still another embodiment of compounds of Formula (IV),
R.sup.25 is aryl, substituted aryl, arylalkyl, substituted
arylalkyl, heteroaryl or substituted heteroaryl, and R.sup.13 and
R.sup.14 are independently hydrogen, alkyl, substituted alkyl,
alkoxycarbonyl, substituted alkoxycarbonyl, aryl, substituted aryl,
arylalkyl, substituted arylalkyl, carbamoyl, cycloalkyl,
substituted cycloalkyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl, heteroaryl or substituted heteroaryl
(preferably, when R.sup.13 is alkoxycarbonyl, substituted
alkoxycarbonyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl or carbamoyl then R.sup.14 is methyl).
Preferably R.sup.25 is phenyl, 4-methoxyphenyl, benzyl, phenethyl,
styryl or 3-pyridyl and R.sup.13 and R.sup.14 are independently
hydrogen, alkyl, substituted alkyl, alkoxycarbonyl, substituted
alkoxycarbonyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, carbamoyl, cycloalkyl, substituted cycloalkyl,
cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl, heteroaryl or
substituted heteroaryl (preferably, when R.sup.13 is
alkoxycarbonyl, cycloalkoxycarbonyl or carbamoyl then R.sup.14 is
methyl).
[0149] In still another embodiment of compounds of Formula (IV),
R.sup.25 is cycloalkyl or substituted cycloalkyl, and R.sup.13 and
R.sup.14 are independently hydrogen, alkyl, substituted alkyl,
alkoxycarbonyl, substituted alkoxycarbonyl, aryl, substituted aryl,
arylalkyl, substituted arylalkyl, carbamoyl, cycloalkyl,
substituted cycloalkyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl, heteroaryl or substituted heteroaryl
(preferably, when R.sup.13 is alkoxycarbonyl, substituted
alkoxycarbonyl, cycloalkoxycarbonyl, substituted
cycloalkoxycarbonyl or carbamoyl then R.sup.14 is methyl).
Preferably, R.sup.25 is cyclopropyl, cyclobutyl, cyclopentyl or
cyclohexyl and R.sup.13 and R.sup.14 are independently hydrogen,
alkyl, substituted alkyl, alkoxycarbonyl, substituted
alkoxycarbonyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, carbamoyl, cycloalkyl, substituted cycloalkyl,
cycloalkoxycarbonyl, substituted cycloalkoxycarbonyl, heteroaryl or
substituted heteroaryl (preferably, when R.sup.13 is
alkoxycarbonyl, cycloalkoxycarbonyl or carbamoyl then R.sup.14 is
methyl).
[0150] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroalkyl, substituted heteroalkyl, heteroaryl,
substituted heteroaryl, heteroarylalkyl or substituted
heteroarylalkyl, and R.sup.13 and R.sup.14 are independently
hydrogen, alkyl, substituted alkyl, aryl, arylalkyl, cycloalkyl or
heteroaryl. Preferably, R.sup.25 is acyl, substituted acyl, alkyl,
substituted alkyl, aryl, arylalkyl, cycloalkyl or heteroaryl and
R.sup.13 and R.sup.14 are independently hydrogen, alkanyl,
substituted alkanyl, cycloalkanyl or substituted cycloalkanyl. More
preferably, R.sup.25 is acyl, substituted acyl, alkyl, substituted
alkyl, aryl, arylalkyl, cycloalkyl or heteroaryl and R.sup.13 and
R.sup.14 are independently hydrogen, methyl, ethyl, propyl,
isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, cyclopentyl or
cyclohexyl. In the above embodiments, R.sup.25 is preferably
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl.
[0151] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
arylalkyl, cycloalkyl or heteroaryl and R.sup.13 and R.sup.14 are
independently hydrogen, alkyl, substituted alkyl, aryl, arylalkyl,
cycloalkyl or heteroaryl. Preferably, R.sup.25 is acyl, substituted
acyl, alkyl, substituted alkyl, aryl, arylalkyl, cycloalkyl or
heteroaryl and R.sup.13 and R.sup.14 are independently hydrogen,
aryl, arylalkyl or heteroaryl. More preferably, R.sup.25 is acyl,
substituted acyl, alkyl, substituted alkyl, aryl, arylalkyl,
cycloalkyl or heteroaryl and R.sup.13 and R.sup.14 are
independently hydrogen, phenyl, benzyl, phenethyl or 3-pyridyl. In
the above embodiments, R.sup.25 is preferably methyl, ethyl,
propyl, isopropyl, butyl, isobutyl, sec-butyl, pentyl, isopentyl,
sec-pentyl, neopentyl, 1,1-dimethoxyethyl, 1,1-diethoxyethyl,
1-(1,3-dioxolan-2-yl)-ethyl, 1-(1,3-dioxan-2-yl)-ethyl,
1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl.
[0152] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
arylalkyl, cycloalkyl or heteroaryl and R.sup.13 and R.sup.14 are
independently hydrogen, alkyl, substituted alkyl, aryl, arylalkyl,
cycloalkyl or heteroaryl. Preferably, R.sup.25 is acyl, substituted
acyl, alkyl, substituted alkyl, aryl, arylalkyl, cycloalkyl or
heteroaryl and R.sup.13 and R.sup.14 are independently hydrogen,
alkyl, substituted alkyl, alkoxycarbonyl, substituted
alkoxycarbonyl, carbamoyl, cycloalkoxycarbonyl or substituted
cycloalkoxycarbonyl (preferably, when R.sup.13 is alkoxycarbonyl,
substituted alkoxycarbonyl, carbamoyl, cycloalkoxycarbonyl or
substituted cycloalkoxycarbonyl then R.sup.14 is methyl; more
preferably, R.sup.13 is methoxycarbonyl, ethoxycarbonyl,
propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl,
isobutoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl or
cyclohexyloxycarbonyl, and R.sup.14 is methyl). In the above
embodiments, R.sup.25 is preferably methyl, ethyl, propyl,
isopropyl, butyl, isobutyl, sec-butyl, pentyl, isopentyl,
sec-pentyl, neopentyl, 1,1-dimethoxyethyl, 1,1-diethoxyethyl,
1-(1,3-dioxolan-2-yl)-ethyl, 1-(1,3-dioxan-2-yl)-ethyl,
1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl.
[0153] In still another embodiment of compounds of Formula (IV),
R.sup.25 is acyl, substituted acyl, alkyl, substituted alkyl, aryl,
arylalkyl, cycloalkyl or heteroaryl and R.sup.13 and R.sup.14
together with the atom to which they are attached form a
cycloalkyl, substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring. Preferably, R.sup.25 is acyl, substituted
acyl, alkyl, substituted alkyl, aryl, arylalkyl, cycloalkyl or
heteroaryl and R.sup.13 and R.sup.14 together with the atom to
which they are attached form a cycloalkyl or substituted cycloalkyl
ring. More preferably R.sup.25 is acyl, substituted acyl, alkyl,
substituted alkyl, aryl, arylalkyl, cycloalkyl or heteroaryl, and
R.sup.13 and R.sup.14 together with the atom to which they are
attached form a cyclobutyl, cyclopentyl or cyclohexyl ring. In the
above embodiments, R.sup.25 is preferably methyl, ethyl, propyl,
isopropyl, butyl, isobutyl, sec-butyl, pentyl, isopentyl,
sec-pentyl, neopentyl, 1,1-dimethoxyethyl, 1,1-diethoxyethyl,
1-(1,3-dioxolan-2-yl)-ethyl, 1-(1,3-dioxan-2-yl)-ethyl,
1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl or 3-pyridyl.
[0154] In still another embodiment of compounds of Formulae (I) and
(III), R.sup.1 is
##STR00013##
[0155] m is 0, and R.sup.8, R.sup.11 and R.sup.12 are as previously
defined.
[0156] In one embodiment of compounds of Formulae (I) and (III),
R.sup.11 is acyl, alkoxycarbonyl, aryloxycarbonyl,
cycloalkoxycarbonyl or carbamoyl, R.sup.8 is hydrogen,
alkoxycarbonyl, alkyl, aryl, arylalkyl or cyano and R.sup.12 is
hydrogen, alkoxycarbonyl, alkyl, substituted alkyl, aryl, or
arylalkyl.
[0157] In another embodiment of compounds of Formulae (I) and
(III), R.sup.11 is selected from the group consisting of acetyl,
propionyl, butyryl, isobutyryl, pivaloyl, cyclopentanecarbonyl,
cyclohexanecarbonyl, benzoyl, phenacetyl, methoxycarbonyl,
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl,
butoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl,
tert-butoxycarbonyl, cyclopentyloxycarbonyl, cyclohexyloxycarbonyl,
phenoxycarbonyl, benzyloxycarbonyl, carbamoyl, N-methylcarbamoyl,
N-ethylcarbamoyl, N-propylcarbamoyl, N-isopropylcarbamoyl,
N-butylcarbamoyl, N-isobutylcarbamoyl, N-sec-butylcarbamoyl,
N-tert-butylcarbamoyl, N-cyclopentylcarbamoyl,
N-cyclohexylcarbamoyl, N-phenylcarbamoyl, N-benzylcarbamoyl,
N,N-dimethylcarbamoyl, N,N-diethylcarbamoyl, N,N-dipropylcarbamoyl,
N,N-diisopropylcarbamoyl, N,N-dibutylcarbamoyl,
N,N-dibenzylcarbamoyl, N-pyrrolidinylcarbamoyl,
N-piperidinylcarbamoyl and N-morpholinylcarbamoyl. More preferably,
R.sup.11 is selected from the group consisting of acetyl,
propionyl, butyryl, isobutyryl, cyclohexanecarbonyl, benzoyl,
phenacetyl, methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl,
isopropoxycarbonyl, butoxycarbonyl, cyclohexyloxycarbonyl,
phenoxycarbonyl, benzyloxycarbonyl, carbamoyl, N-methylcarbamoyl,
N-ethylcarbamoyl, N-propylcarbamoyl, N-isopropylcarbamoyl,
N-phenylcarbamoyl, N-benzylcarbamoyl, N,N-dimethylcarbamoyl,
N,N-diethylcarbamoyl, N,N-dipropylcarbamoyl,
N-pyrrolidinylcarbamoyl, N-piperidinylcarbamoyl and
N-morpholinylcarbamoyl.
[0158] In still another embodiment of compounds of Formulae (I) and
(III), R.sup.8 is selected from the group consisting of hydrogen,
methyl, ethyl, propyl, isopropyl, phenyl, benzyl, methoxycarbonyl,
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl,
butoxycarbonyl, phenoxycarbonyl, benzyloxycarbonyl and cyano. More
preferably R.sup.8 is selected from the group consisting of
hydrogen, methyl, ethyl, isopropyl, phenyl, benzyl,
methoxycarbonyl, ethoxycarbonyl and butoxycarbonyl.
[0159] In still another embodiment of compounds of Formulae (I) and
(III), R.sup.12 is selected from the group consisting of hydrogen,
methyl, ethyl, propyl, isopropyl, phenyl, benzyl, methoxycarbonyl,
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl,
butoxycarbonyl, phenoxycarbonyl and benzyloxycarbonyl. More
preferably R.sup.12 is selected from the group consisting of
hydrogen, methyl, ethyl, isopropyl, phenyl, benzyl,
methoxycarbonyl, ethoxycarbonyl and butoxycarbonyl.
[0160] In still another embodiment of compounds of Formulae (I) and
(III), R.sup.11 is selected from the group consisting of hydrogen,
alkoxycarbonyl, alkyl, substituted alkyl, aryl, arylalkyl and
R.sup.8 and R.sup.12 together with the carbon atoms to which they
are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably,
R.sup.11 is selected from the group consisting of hydrogen, methyl,
ethyl, isopropyl, phenyl, benzyl, methoxycarbonyl, ethoxycarbonyl
and butoxycarbonyl, and R.sup.8 and R.sup.12 together with the
carbon atoms to which they are attached form a cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring. More preferably, R.sup.11 is hydrogen or
methyl and R.sup.8 and R.sup.12 together with the carbon atoms to
which they are attached form a cyclopent-1-ene, cyclohex-1-ene,
2-cyclopenten-1-one, 2-cyclohexen-1-one, 2-(5H)-furanone or
5,6-dihydro-pyran-2-one ring.
[0161] In still another embodiment of compounds of Formulae (I) and
(III), R.sup.12 is selected from the group consisting of hydrogen,
alkoxycarbonyl, alkyl, substituted alkyl, aryl, arylalkyl and
R.sup.8 and R.sup.11 together with the carbon atoms to which they
are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably,
R.sup.12 is selected from the group consisting of hydrogen, methyl,
ethyl, isopropyl, phenyl, benzyl, methoxycarbonyl, ethoxycarbonyl
and butoxycarbonyl, and R.sup.8 and R.sup.11 together with the
carbon atoms to which they are attached form a cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring. More preferably, R.sup.12 is selected from
the group consisting of hydrogen, methyl, ethyl, isopropyl, phenyl,
benzyl, methoxycarbonyl, ethoxycarbonyl and butoxycarbonyl, and
R.sup.8 and R.sup.11 together with the carbon atoms to which they
are attached form a .gamma.-butyrolactone, .delta.-valerolactone or
2,2-dimethyl-1,3-dioxan-4,6-dione ring.
[0162] In still another embodiment of compounds of Formulae (I) and
(III), R.sup.1 is
##STR00014##
[0163] and R.sup.15 is selected from the group consisting of alkyl,
substituted alkyl, cycloalkyl, substituted cycloalkyl, aryl,
substituted aryl, heteroaryl and substituted heteroaryl.
Preferably, R.sup.15 is methyl, ethyl, propyl, isopropyl,
cyclopentyl, cyclohexyl, phenyl, 4-hydroxyphenyl, benzyl,
4-hydroxybenzyl or 3-pyridyl.
[0164] In still another embodiment, of Formulae (I) and (III),
R.sup.1 is
##STR00015##
[0165] where R.sup.37 is hydrogen, alkyl, substituted alkyl, acyl,
aryl, substituted aryl, arylalkyl, substituted arylalkyl,
cycloalkyl, heterocycloalkyl, substituted cycloheteroalkyl,
heteroaryl, substituted heteroaryl, heteroarylalkyl or substituted
heteroarylalkyl;
[0166] Z is O, N or S; and
[0167] Ar is aryl, substituted aryl, heteroaryl or substituted
heteroaryl.
Preferably, Z and CH.sub.2OC(O)-- are in a conjugated relationship
with one another (e.g., 1.4 or 1.2 related in a six membered ring
system).
[0168] In still another embodiment, of Formulas (I) and (I),
R.sup.1 is
##STR00016##
[0169] where q is 0 or 1;
[0170] R.sup.38 and R.sup.39 are independently hydrogen, alkyl,
substituted alkyl, cycloalkyl, substituted alkyl, aryl, substituted
aryl, heteroaryl and substituted heteroaryl;
[0171] R.sup.40 and R.sup.41 are independently hydrogen, alkyl,
substituted alkyl, cycloalkyl, substituted alkyl, aryl, substituted
aryl, heteroaryl and substituted heteroaryl; or together with the
carbon atom to which they are attached form a cycloalkyl ring
[0172] R.sup.42 and R.sup.43 are independently alkyl, substituted
alkyl, cycloalkyl, substituted alkyl, aryl, substituted aryl,
heteroaryl and substituted aryl or together with the carbon atoms
to which they are attached form an aryl, substituted aryl,
heteroaryl or substituted aryl ring; and
[0173] R.sup.37 is as previously defined.
[0174] In a preferred embodiment of compounds of Formulae (I)-(IV),
Y is O, R.sup.3, R.sup.6 and R.sup.7 are hydrogen and R.sup.4 and
R.sup.5 together with the carbon atom to which they are attached
form a cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,
substituted cycloheteroalkyl, bridged cycloalkyl or substituted
bridged cycloalkyl ring. In another preferred embodiment of
compounds of Formulae (I)-(IV), R.sup.4 and R.sup.5 together with
the carbon atom to which they are attached form a cycloalkyl or
substituted cycloalkyl ring. In one embodiment n is 0, t is 0 and u
is 0. In another embodiment, n is 1 and R.sup.2 is hydrogen,
methyl, 2-propyl, 2-butyl, isobutyl, t-butyl, cyclopentyl,
cyclohexyl, phenyl, benzyl, 4-hydroxybenzyl, 4-bromobenzyl,
2-imidazolyl, 2-indolyl, --CH.sub.2OH, --CH(OH)CH.sub.3,
--CH.sub.2CO.sub.2H, --CH.sub.2CH.sub.2CO.sub.2H,
--CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2CONH.sub.2,
--CH.sub.2SCH.sub.3, CH.sub.2SH, --CH.sub.2(CH.sub.2).sub.3NH.sub.2
or --CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. In still another
embodiment, n is 1 and R.sup.2 and R.sup.16 together with the atoms
to which they are attached form a pyrrolidine ring.
[0175] In still another preferred embodiment of compounds of
Formulae (I)-(IV), R.sup.4 and R.sup.5 together with the carbon
atom to which they are attached form a cyclobutyl or substituted
cyclobutyl ring. Preferably, the substituted cyclobutyl ring is
substituted with one or more substituents selected from the group
consisting of alkanyl, substituted alkanyl, halo, hydroxy, carboxyl
and alkoxycarbonyl.
[0176] In still another preferred embodiment of compounds of
Formulae (I)-(IV), R.sup.4 and R.sup.5 together with the carbon
atom to which they are attached form a cyclopentyl or substituted
cyclopentyl ring. Preferably, the cyclopentyl ring is substituted
with alkanyl, substituted alkanyl, halo, hydroxy, carboxyl or
alkoxycarbonyl. More preferably, the cyclopentyl ring is
substituted with alkanyl. Even more preferably, the cyclopentyl
ring is selected from the group consisting of
##STR00017##
[0177] Preferably, in a more specific version of the above
embodiments, R.sup.7 is hydrogen.
[0178] In still another preferred embodiment of compounds of
Formulae (I)-(IV), R.sup.4 and R.sup.5 together with the carbon
atom to which they are attached form a cyclohexyl or substituted
cyclohexyl ring. Preferably, the cyclohexyl ring is substituted
with alkanyl, substituted alkanyl, halo, hydroxy, carboxyl or
alkoxycarbonyl. More preferably, the cyclohexyl ring is substituted
with alkanyl. Even more preferably, the cyclohexyl ring is selected
from the group consisting of
##STR00018##
[0179] Preferably, in a more specific version of the above
embodiments, R.sup.7 is hydrogen.
[0180] In still another preferred embodiment of compounds of
Formulae (I)-(IV), R.sup.4 and R.sup.5 together with the carbon
atom to which they are attached form a cycloheteroalkyl or
substituted cycloheteroalkyl ring.
[0181] In one embodiment, n is 0. In another embodiment, n is 1,
and R.sup.2 is hydrogen, methyl, 2-propyl, 2-butyl, isobutyl,
t-butyl, cyclopentyl, cyclohexyl, phenyl, benzyl, 4-hydroxybenzyl,
4-bromobenzyl, 2-imidazolyl, 2-indolyl, --CH.sub.2OH,
--CH(OH)CH.sub.3, --CH.sub.2CO.sub.2H, --CH.sub.2CH.sub.2CO.sub.2H,
--CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2SCH.sub.3, CH.sub.2SH,
--CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. In still another
embodiment, n is 1 and R.sup.2 and R.sup.16 together with the atoms
to which they are attached form a pyrrolidine ring. Preferably,
R.sup.4 and R.sup.5 together with the carbon atom to which they are
attached form a cycloheteroalkanyl ring. More preferably, the
cycloheteroalkanyl ring is selected from the group consisting
of
##STR00019##
[0182] wherein Z is O, S(O).sub.p or NR.sup.18;
[0183] p is 0, 1 or 2; and
[0184] R.sup.18 is is selected from the group consisting of
hydrogen, alkyl, substituted alkyl, acyl and alkoxycarbonyl. More
preferably, the cycloheteroalkanyl ring is selected from the group
consisting of
##STR00020##
[0185] Preferably, in a more specific version of the above
embodiments, R.sup.7 is hydrogen.
[0186] In still another embodiment of compounds of Formulae
(I)-(IV), R.sup.4 and R.sup.5 together with the carbon atom to
which they are attached form a bridged cycloalkyl ring. In one
embodiment, n is 0. In another embodiment, n is 1 and R.sup.2 is
hydrogen, methyl, 2-propyl, 2-butyl, isobutyl, t-butyl,
cyclopentyl, cyclohexyl, phenyl, benzyl, 4-hydroxybenzyl,
4-bromobenzyl, 2-imidazolyl, 2-indolyl, --CH.sub.2OH,
--CH(OH)CH.sub.3, --CH.sub.2CO.sub.2H, --CH.sub.2CH.sub.2CO.sub.2H,
--CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2SCH.sub.3, CH.sub.2SH,
--CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. In another embodiment, n
is 1 and R2 and R.sup.16 together with the atoms to which they are
attached form a pyrrolidine ring. Preferably, the bridged
cycloalkyl group is
##STR00021##
[0187] Preferably, in a more specific version of the above
embodiments, R.sup.7 is hydrogen.
[0188] In still another embodiment of compounds of Formulae
(I)-(IV), Y is O, R.sup.6 and R.sup.7 are hydrogen, R.sup.4 is
alkyl or cycloalkyl, R.sup.5 is hydrogen or alkyl and R.sup.3 is
hydrogen or alkyl. In one embodiment, n is 0. In another
embodiment, n is 1 and R.sup.2 is hydrogen, methyl, 2-propyl,
2-butyl, isobutyl, t-butyl, cyclopentyl, cyclohexyl, phenyl,
benzyl, 4-hydroxybenzyl, 4-bromobenzyl, 2-imidazolyl, 2-indolyl,
--CH.sub.2OH, --CH(OH)CH.sub.3, --CH.sub.2CO.sub.2H,
--CH.sub.2CH.sub.2CO.sub.2H, --CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2SCH.sub.3,
CH.sub.2SH, --CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. In still another
embodiment, n is 1 and R.sup.2 and R.sup.16 together with the atoms
to which they are attached form a pyrrolidine ring. Preferably,
R.sup.4 is cycloalkyl, R.sup.5 is hydrogen or methyl, and R.sup.3
is hydrogen or methyl. Preferably, R.sup.3 is hydrogen, R.sup.4 is
isobutyl and R.sup.5 is hydrogen.
[0189] In still another embodiment of compounds of Formulae
(I)-(IV), Y is O, R.sup.5 and R.sup.7 are hydrogen or alkanyl,
R.sup.3 and R.sup.6 are hydrogen and R.sup.4 is substituted
heteroalkyl. Preferably, R.sup.4 is
##STR00022##
[0190] A is NR.sup.19, O or S;
[0191] B is alkyl, substituted alkyl, alkoxy, halogen, hydroxy,
carboxyl, alkoxycarbonyl or amino;
[0192] R.sup.19 is hydrogen, alkyl, cycloalkyl or aryl;
[0193] j is an integer from 0 to 4;
[0194] k is an integer from 1 to 4; and
[0195] l is an integer from 0 to 3.
[0196] More preferably, k is 1.
[0197] In still another embodiment of compounds of Formulae
(I)-(IV), Y is O, R.sup.5 and R.sup.7 are hydrogen or alkanyl,
R.sup.3 and R.sup.6 are hydrogen and R.sup.4 is substituted
alkanyl, cycloalkanyl or substituted cycloalkanyl. Preferably,
R.sup.4 is selected from the group consisting of
##STR00023##
[0198] Preferably, R.sup.4 is
##STR00024##
[0199] h is an integer from 1 to 6; and
[0200] i is an integer from 0 to 6.
[0201] More preferably, h is 1, 2, 3 or 4 and i is 0 or 1. Even
more preferably, R.sup.4 is selected from the group consisting
of
##STR00025##
[0202] Preferably, compounds of Formulae (I)-(IV) are derived from
a GABA analog of Formula (XIII):
##STR00026##
[0203] wherein the GABA analog of Formula (XIII) is selected from
the group consisting of: [0204] 1-Aminomethyl-1-cyclohexane acetic
acid; [0205] 1-Aminomethyl-1-(3-methylcyclohexane) acetic acid;
[0206] 1-Aminomethyl-1-(4-methylcyclohexane) acetic acid; [0207]
1-Aminomethyl-1-(4-isopropylcyclohexane) acetic acid; [0208]
1-Aminomethyl-1-(4-tert-butylcyclohexane) acetic acid; [0209]
1-Aminomethyl-1-(3,3-dimethylcyclohexane) acetic acid; [0210]
1-Aminomethyl-1-(3,3,5,5-tetramethylcyclohexane) acetic acid;
[0211] 1-Aminomethyl-1-cyclopentane acetic acid; [0212]
1-Aminomethyl-1-(3-methylcyclopentane) acetic acid; [0213]
1-Aminomethyl-1-(3,4-dimethylcyclopentane) acetic acid; [0214]
7-Aminomethyl-bicyclo[2.2.1]hept-7-yl acetic acid; [0215]
9-Aminomethyl-bicyclo[3.3.1]non-9-yl acetic acid; [0216]
4-Aminomethyl-4-(tetrahydropyran-4-yl) acetic acid; [0217]
3-Aminomethyl-3-(tetrahydropyran-3-yl) acetic acid; [0218]
4-Aminomethyl-4-(tetrahydrothiopyran-4-yl) acetic acid; [0219]
3-Aminomethyl-3-(tetrahydrothiopyran-3-yl) acetic acid; [0220]
3-Aminomethyl-5-methyl-hexanoic acid; [0221]
3-Aminomethyl-5-methyl-heptanoic acid; [0222]
3-Aminomethyl-5-methyl-octanoic acid; [0223]
3-Aminomethyl-5-methyl-nonanoic acid; [0224]
3-Aminomethyl-5-methyl-decanoic acid; [0225]
3-Aminomethyl-5-cyclopropyl-hexanoic acid; [0226]
3-Aminomethyl-5-cyclobutyl-hexanoic acid; [0227]
3-Aminomethyl-5-cyclopentyl-hexanoic acid; [0228]
3-Aminomethyl-5-cyclohexyl-hexanoic acid; [0229]
3-Aminomethyl-5-phenyl-hexanoic acid; [0230]
3-Aminomethyl-5-phenyl-pentanoic acid; [0231]
3-Aminomethyl-4-cyclobutyl-butyric acid; [0232]
3-Aminomethyl-4-cyclopentyl-butyric acid; [0233]
3-Aminomethyl-4-cyclohexyl-butyric acid; [0234]
3-Aminomethyl-4-phenoxy-butyric acid; [0235]
3-Aminomethyl-5-phenoxy-hexanoic acid; and [0236]
3-Aminomethyl-5-benzyl sulfanyl-pentanoic acid.
[0237] Particularly preferred embodiments of Formula (I) include
compounds of Formulae
##STR00027##
(V) and (VI):
[0238] where R.sup.1, R.sup.2, R.sup.7 and R.sup.16 are as
previously defined.
[0239] In one embodiment of compounds of Formulae (V) and (VI), n
is 0. In another embodiment, n is 1 and R.sup.2 is hydrogen,
methyl, 2-propyl, 2-butyl, isobutyl, t-butyl, cyclopentyl,
cyclohexyl, phenyl, benzyl, 4-hydroxybenzyl, 4-bromobenzyl,
2-imidazolyl, 2-indolyl, --CH.sub.2OH, --CH(OH)CH.sub.3,
--CH.sub.2CO.sub.2H, --CH.sub.2CH.sub.2CO.sub.2H,
--CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2SCH.sub.3, --CH.sub.2SH,
--CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. Preferably, in the above
embodiments, R.sup.7 is hydrogen.
[0240] In another embodiment of compounds of Formulae (V) and (VI),
n is 1, R.sup.1 is R.sup.24C(O)-- or R.sup.24C(S)--; and R.sup.24
is alkyl, substituted alkyl, heteroalkyl, aryl, substituted aryl,
heteroaryl or substituted heteroaryl. Preferably, R.sup.24 is
methyl, ethyl, 2-propyl, t-butyl, --CH.sub.2OCH(CH.sub.3).sub.2,
phenyl or 3-pyridyl. Preferably, in this embodiment, R.sup.7 is
hydrogen, alkanyl, substituted alkanyl, alkenyl, substituted
alkenyl, aryl or substituted aryl. More preferably, R.sup.7 is
hydrogen, methyl, ethyl, benzyl, --C(CH.sub.3).dbd.CH.sub.2,
--CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00028##
[0241] where V is O or CH.sub.2.
[0242] Most preferably, R.sup.7 is hydrogen.
[0243] In still another embodiment of compounds of Formulae (V) and
(VI), n is 1, R.sup.1 is R.sup.25OC(O)-- or R.sup.25SC(O)--; and
R.sup.25 is alkyl, substituted alkyl, heteroalkyl, aryl,
substituted aryl, heteroaryl or substituted heteroaryl. Preferably,
R.sup.25 is ethyl, 2-propyl, neopentyl,
--CH.sub.2OCH(CH.sub.3).sub.2, phenyl or 2-pyridyl. Preferably in
this embodiment, R.sup.7 is hydrogen, alkanyl, substituted alkanyl,
alkenyl, substituted alkenyl, aryl or substituted aryl. More
preferably, R.sup.7 is hydrogen, methyl, ethyl, benzyl,
--C(CH.sub.3).dbd.CH.sub.2, --CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00029##
[0244] where V is O or CH.sub.2.
[0245] Most preferably, R.sup.7 is hydrogen.
[0246] In still another embodiment of compounds of Formulae (V) and
(VI), R.sup.1 is
##STR00030##
and R.sup.15 is selected from the group consisting of alkyl,
substituted alkyl, cycloalkyl, substituted cycloalkyl, aryl,
substituted aryl, heteroaryl and substituted heteroaryl.
Preferably, R.sup.15 is methyl, ethyl, propyl, isopropyl,
cyclopentyl, cyclohexyl, phenyl, 4-hydroxyphenyl, benzyl,
4-hydroxybenzyl or 3-pyridyl. In a more specific version of this
embodiment, R.sup.7 is hydrogen, alkanyl, substituted alkanyl,
alkenyl, substituted alkenyl, aryl or substituted aryl. More
preferably, R.sup.7 is hydrogen, methyl, ethyl, benzyl,
--C(CH.sub.3).dbd.CH.sub.2, --CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00031##
[0247] where V is O or CH.sub.2.
[0248] Preferably, R.sup.7 is hydrogen.
[0249] Particularly preferred embodiments of compounds of Formulae
(V) and (VI) are compounds selected from the group consisting of:
[0250]
1-{[((5-methyl-2-oxo-1,3-dioxol-4-en-4-yl)methoxy)carbonyl]aminomethyl}-1-
-cyclohexane acetic acid; and [0251]
3-{[((5-methyl-2-oxo-1,3-dioxol-4-en-4-yl)methoxy)carbonyl]aminomethyl}-5-
-methyl-hexanoic acid.
[0252] In still another embodiment of compounds of Formulae (V) and
(VI), R.sup.1 is
##STR00032##
m is 0, and R.sup.8, R.sup.11 and R.sup.12 are as previously
defined. In one embodiment of compounds of Formulae (V) and (VI),
R.sup.11 is acyl, alkoxycarbonyl, aryloxycarbonyl,
cycloalkoxycarbonyl, carbamoyl or substituted carbamoyl, R.sup.8 is
hydrogen, alkoxycarbonyl, alkyl, aryl, arylalkyl or cyano and
R.sup.12 is hydrogen, alkoxycarbonyl, alkyl, substituted alkyl,
aryl, or arylalkyl. In another embodiment of compounds of Formulae
(V) and (VI), R.sup.11 is selected from the group consisting of
acetyl, propionyl, butyryl, isobutyryl, pivaloyl,
cyclopentanecarbonyl, cyclohexanecarbonyl, benzoyl, phenacetyl,
methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl,
isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl,
sec-butoxycarbonyl, tert-butoxycarbonyl, cyclopentyloxycarbonyl,
cyclohexyloxycarbonyl, phenoxycarbonyl, benzyloxycarbonyl,
carbamoyl, N-methylcarbamoyl, N-ethylcarbamoyl, N-propylcarbamoyl,
N-isopropylcarbamoyl, N-butylcarbamoyl, N-isobutylcarbamoyl,
N-sec-butylcarbamoyl, N-tert-butylcarbamoyl,
N-cyclopentylcarbamoyl, N-cyclohexylcarbamoyl, N-phenylcarbamoyl,
N-benzylcarbamoyl, N,N-dimethylcarbamoyl, N,N-diethylcarbamoyl,
N,N-dipropylcarbamoyl, N,N-diisopropylcarbamoyl,
N,N-dibutylcarbamoyl, N,N-dibenzylcarbamoyl,
N-pyrrolidinylcarbamoyl, N-piperidinylcarbamoyl and
N-morpholinylcarbamoyl. In still another embodiment of compounds of
Formulae (V) and (VI), R.sup.11 is selected from the group
consisting of acetyl, propionyl, butyryl, isobutyryl,
cyclohexanecarbonyl, benzoyl, phenacetyl, methoxycarbonyl,
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl,
butoxycarbonyl, cyclohexyloxycarbonyl, phenoxycarbonyl,
benzyloxycarbonyl, carbamoyl, N-methylcarbamoyl, N-ethylcarbamoyl,
N-propylcarbamoyl, N-isopropylcarbamoyl, N-phenylcarbamoyl,
N-benzylcarbamoyl, N,N-dimethylcarbamoyl, N,N-diethylcarbamoyl,
N,N-dipropylcarbamoyl, N-pyrrolidinylcarbamoyl,
N-piperidinylcarbamoyl and N-morpholinylcarbamoyl.
[0253] In one embodiment of compounds of Formulae (V) and (VI),
R.sup.8 is selected from the group consisting of hydrogen, methyl,
ethyl, propyl, isopropyl, phenyl, benzyl, methoxycarbonyl,
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl,
butoxycarbonyl, phenoxycarbonyl, benzyloxycarbonyl and cyano.
Preferably, R.sup.8 is selected from the group consisting of
hydrogen, methyl, ethyl, isopropyl, phenyl, benzyl,
methoxycarbonyl, ethoxycarbonyl and butoxycarbonyl.
[0254] In still another embodiment of compounds of Formulae (V) and
(VI), R.sup.12 is selected from the group consisting of hydrogen,
methyl, ethyl, propyl, isopropyl, phenyl, benzyl, methoxycarbonyl,
ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl,
butoxycarbonyl, phenoxycarbonyl and benzyloxycarbonyl. Preferably
R.sup.12 is selected from the group consisting of hydrogen, methyl,
ethyl, isopropyl, phenyl, benzyl, methoxycarbonyl, ethoxycarbonyl
and butoxycarbonyl.
[0255] In still another embodiment of compounds of Formulae (V) and
(VI), R.sup.11 is selected from the group consisting of hydrogen,
alkoxycarbonyl, alkyl, substituted alkyl, aryl, arylalkyl and
R.sup.8 and R.sup.12 together with the carbon atoms to which they
are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably,
R.sup.11 is selected from the group consisting of hydrogen, methyl,
ethyl, isopropyl, phenyl, benzyl, methoxycarbonyl, ethoxycarbonyl
and butoxycarbonyl, and R.sup.8 and R.sup.12 together with the
carbon atoms to which they are attached form a cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring. More preferably, R.sup.11 is hydrogen or
methyl and R.sup.8 and R.sup.12 together with the carbon atoms to
which they are attached form a 2-cyclopenten-1-one,
2-cyclohexen-1-one, 2-(5H)-furanone or 5,6-dihydro-pyran-2-one
ring.
[0256] In still another embodiment of compounds of Formulae (V) and
(VI), R.sup.12 is selected from the group consisting of hydrogen,
alkoxycarbonyl, alkyl, substituted alkyl, aryl, arylalkyl and
R.sup.8 and R.sup.11 together with the carbon atoms to which they
are attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl or substituted cycloheteroalkyl ring. Preferably,
R.sup.12 is selected from the group consisting of hydrogen, methyl,
ethyl, isopropyl, phenyl, benzyl, methoxycarbonyl, ethoxycarbonyl
and butoxycarbonyl, and R.sup.8 and R.sup.11 together with the
carbon atoms to which they are attached form a cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl or substituted
cycloheteroalkyl ring. More preferably, R.sup.12 is selected from
the group consisting of hydrogen, methyl, ethyl, isopropyl, phenyl,
benzyl, methoxycarbonyl, ethoxycarbonyl and butoxycarbonyl, and
R.sup.8 and R.sup.11 together with the carbon atoms to which they
are attached form a .gamma.-butyrolactone, .delta.-valerolactone or
2,2-dimethyl-1,3-dioxan-4,6-dione ring.
[0257] In a more specific version of the above embodiments of
compounds of Formulae (V) and (VI), R.sup.7 is hydrogen, alkanyl,
substituted alkanyl, alkenyl, substituted alkenyl, aryl or
substituted aryl. More preferably, R.sup.7 is hydrogen, methyl,
ethyl, benzyl, --C(CH.sub.3).dbd.CH.sub.2,
--CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00033## [0258] where V is O or CH.sub.2.
[0259] Most preferably R.sup.7 is hydrogen.
[0260] Particularly preferred embodiments of compounds of Formulae
(V) and (VI) are compounds selected from the group consisting of:
[0261] Piperidinium
1-{(1-methyl-3-oxo-but-1-enyl)aminomethyl}-1-cyclohexane acetate;
[0262] Piperidinium
1-{1-[(2-oxo-tetrahydrofuran-3-ylidene)ethyl]aminomethyl}-1-cyclohexane
acetate; [0263] Piperidinium
1-{(2-carbomethoxy-cyclopent-1-enyl)aminomethyl}-1-cyclohexane
acetate; and [0264] Piperidinium
1-{(1-methyl-2-(ethoxycarbonyl)-3-ethoxy-3-oxoprop-1-enyl)aminomethyl}-1--
cyclohexane acetate.
[0265] In a particularly preferred embodiment, compounds of Formula
(IV) have the structure of Formulae (VII) or (VIII):
##STR00034##
[0266] or a pharmaceutically acceptable salt, hydrate or solvate
thereof, wherein:
[0267] n, R.sup.2, R.sup.7, R.sup.13, R.sup.14, R.sup.16 and
R.sup.25 are as previously defined.
[0268] In one preferred embodiment, the compounds of Formulae (VII)
and (VIII) do not include the following compounds:
[0269] if either R.sup.13 or R.sup.14 is hydrogen, alkoxycarbonyl,
substituted alkoxycarbonyl, carbamoyl, cycloalkoxycarbonyl or
substituted cycloalkoxycarbonyl, then the other of R.sup.13 or
R.sup.14 is not hydrogen; and
[0270] R.sup.25C(O) is not a moiety derived from a bile acid.
[0271] In one embodiment of compounds of Formulae (VII) and (VIII),
n is 0. In another embodiment, n is 1. When n is 1, preferably the
.alpha.-amino acid is of the L-stereochemical configuration.
[0272] In another embodiment of compounds of Formulae (VII) and
(VIII), R.sup.7 is hydrogen, alkanyl, substituted alkanyl, alkenyl,
substituted alkenyl, aryl or substituted aryl. Preferably, R.sup.7
is hydrogen, methyl, ethyl, benzyl, --C(CH.sub.3).dbd.CH.sub.2,
--CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00035##
[0273] where V is O or CH.sub.2.
[0274] Most preferably, R.sup.7 is hydrogen.
[0275] In still another embodiment of compounds of Formulae (VII)
and (VIII), n is 0. In still another embodiment of compounds of
Formulae (VII) and (VIII), n is 1, R.sup.16 is hydrogen and R.sup.2
is hydrogen, methyl, 2-propyl, 2-butyl, isobutyl, tert-butyl,
cyclopentyl, cyclohexyl, phenyl, benzyl, 4-hydroxybenzyl,
4-bromobenzyl, 2-imidazolyl, 2-indolyl, --CH.sub.2OH,
--CH(OH)CH.sub.3, --CH.sub.2CO.sub.2H, --CH.sub.2CH.sub.2CO.sub.2H,
--CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2SCH.sub.3, --CH.sub.2SH,
--CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2. Preferably R.sup.16 is
hydrogen and R.sup.2 is hydrogen, methyl, 2-propyl, 2-butyl,
isobutyl, tert-butyl, cyclohexyl, phenyl or benzyl. In still
another embodiment, n is 1 and R.sup.2 and R.sup.16 together with
the atoms to which they are attached form a pyrrolidine ring.
[0276] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
methyl and R.sup.14 is hydrogen.
[0277] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
ethyl and R.sup.14 is hydrogen.
[0278] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
propyl and R.sup.14 is hydrogen.
[0279] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
isopropyl and R.sup.14 is hydrogen.
[0280] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
butyl and R.sup.14 is hydrogen.
[0281] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
isobutyl and R.sup.14 is hydrogen.
[0282] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
sec-butyl and R.sup.14 is hydrogen.
[0283] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
tert-butyl and R.sup.14 is hydrogen.
[0284] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
cyclopentyl and R.sup.14 is hydrogen.
[0285] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
cyclohexyl and R.sup.14 is hydrogen.
[0286] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
methyl and R.sup.14 is methyl.
[0287] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
methoxycarbonyl and R.sup.14 is methyl.
[0288] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
ethoxycarbonyl and R.sup.14 is methyl.
[0289] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
propoxycarbonyl and R.sup.14 is methyl.
[0290] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
isopropoxycarbonyl and R.sup.14 is methyl.
[0291] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
butoxycarbonyl and R.sup.14 is methyl.
[0292] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
isobutoxycarbonyl and R.sup.14 is methyl.
[0293] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
sec-butoxycarbonyl and R.sup.14 is methyl.
[0294] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
tert-butoxycarbonyl and R.sup.14 is methyl.
[0295] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
cyclohexyloxycarbonyl and R.sup.14 is methyl.
[0296] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
phenyl and R.sup.14 is hydrogen.
[0297] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
benzyl and R.sup.14 is hydrogen.
[0298] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
phenethyl and R.sup.14 is hydrogen.
[0299] In still another embodiment of compounds of Formulae (VII)
and (VIII), R.sup.25 is selected from the group consisting of
methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl,
pentyl, isopentyl, sec-pentyl, neopentyl, 1,1-dimethoxyethyl,
1,1-diethoxyethyl, 1-(1,3-dioxolan-2-yl)-ethyl,
1-(1,3-dioxan-2-yl)-ethyl, 1,1-dimethoxypropyl, 1,1-diethoxypropyl,
1-(1,3-dioxolan-2-yl)-propyl, 1-(1,3-dioxan-2-yl)-propyl,
1,1-dimethoxybutyl, 1,1-diethoxybutyl, 1-(1,3-dioxolan-2-yl)-butyl,
1-(1,3-dioxan-2-yl)-butyl, 1,1-dimethoxybenzyl, 1,1-diethoxybenzyl,
1-(1,3-dioxolan-2-yl)-benzyl, 1-(1,3-dioxan-2-yl)-benzyl,
1,1-dimethoxy-2-phenethyl, 1,1-diethoxy-2-phenethyl,
1-(1,3-dioxolan-2-yl)-2-phenethyl, 1-(1,3-dioxan-2-yl)-2-phenethyl,
acetyl, propionyl, butyryl, benzoyl, phenacetyl, phenyl,
4-methoxyphenyl, benzyl, phenethyl, styryl, cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl and 3-pyridyl, R.sup.13 is
3-pyridyl and R.sup.14 is hydrogen.
[0300] Particularly preferred embodiments of compounds of Formulae
(VII) and (VIII) include compounds selected from the group
consisting of: [0301]
1-{[(.alpha.-Acetoxyethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0302]
1-{[(.alpha.-Propanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0303]
1-{[(.alpha.-Butanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0304]
1-{[(.alpha.-Isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0305]
1-{[(.alpha.-Pivaloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0306]
1-{[(.alpha.-Benzoyloxyethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0307]
1-{[(.alpha.-Acetoxybutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0308]
1-{[(.alpha.-Butanoyloxybutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0309]
1-{[(.alpha.-Isobutanoyloxybutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0310]
1-{[(.alpha.-Benzoyloxybutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0311]
1-{[(.alpha.-Acetoxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0312]
1-{[(.alpha.-Propanoyloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0313]
1-{[(.alpha.-Butanoyloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0314]
1-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0315]
1-{[(.alpha.-Pivaloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0316]
1-{[(.alpha.-2,2-Diethoxypropanoyloxyisobutoxy)carbonyl]aminomethyl}-1-cy-
clohexane acetic acid; [0317]
1-{[(.alpha.-2-(1,3-Dioxolan-2-yl)propanoyloxyisobutoxy)carbonyl]aminomet-
hyl}-1-cyclohexane acetic acid; [0318]
1-{[(.alpha.-(2-Amino-2-methylpropanoyl)oxyisobutoxy)carbonyl]aminomethyl-
}-1-cyclohexane acetic acid; [0319]
1-{[(.alpha.-Benzoyloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0320]
1-{[(.alpha.-Nicotinoyloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0321]
1-{[(.alpha.-Acetoxyisopropoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0322]
1-{[(.alpha.-Butanoyloxyisopropoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0323]
1-{[(.alpha.-Isobutanoyloxyisopropoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0324]
1-{[(.alpha.-Benzoyloxyisopropoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0325]
1-{[(.alpha.-Acetoxybenzyloxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0326]
1-{[(.alpha.-Benzoyloxybenzyloxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0327]
1-{[(1-(3-Methylbutanoyloxy)-2-phenylethoxy)carbonyl]aminomethyl}-1-cyclo-
hexane acetic acid; [0328]
1-{[(1-Benzoyloxy-2-phenylethoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid; [0329]
1-{[N-[(.alpha.-Isobutanoyloxyethoxy)carbonyl]-4-bromophenylalaninyl]-ami-
nomethyl}-1-cyclohexane acetic acid; [0330]
3-{[(.alpha.-Isobutanoyloxyethoxy)carbonyl]aminomethyl}-5-methylhexanoic
acid; [0331]
3-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-5-methylhexano-
ic acid; and [0332]
3-{[(.alpha.-Benzoyloxyisobutoxy)carbonyl]aminomethyl}-5-methylhexanoic
acid.
[0333] In one embodiment, the compounds of the invention have the
structure of Formula (II):
##STR00036##
[0334] In an embodiment of compounds of Formula (II), when R.sup.3,
R.sup.5 and R.sup.6 are hydrogen, R.sup.4 is not phenyl or
substituted phenyl. More preferably, R.sup.4 is not
4-chlorophenyl.
[0335] In a preferred embodiment, the compounds of Formula (II)
have the structure of Formulae (IX) and (X):
##STR00037##
[0336] In one embodiment of compounds of Formulae (IX) and (X), t
is 0. In another embodiment, t is 1 and R.sup.2 is hydrogen,
methyl, 2-propyl, 2-butyl, isobutyl, t-butyl, cyclopentyl,
cyclohexyl, phenyl, benzyl, 4-hydroxybenzyl, 4-bromobenzyl,
2-imidazolyl, 2-indolyl, --CH.sub.2OH, --CH(OH)CH.sub.3,
--CH.sub.2CO.sub.2H, --CH.sub.2CH.sub.2CO.sub.2H,
--CH.sub.2CONH.sub.2, --CH.sub.2CH.sub.2CONH.sub.2,
--CH.sub.2CH.sub.2SCH.sub.3, --CH.sub.2SH,
--CH.sub.2(CH.sub.2).sub.3NH.sub.2 or
--CH.sub.2CH.sub.2CH.sub.2NHC(NH)NH.sub.2.
[0337] In still another embodiment of compounds of Formulae (IX) or
(X), R.sup.20 and R.sup.21 are independently selected from the
group consisting of alkyl, substituted alkyl, aryl, substituted
aryl, heteroaryl and substituted heteroaryl. Preferably, R.sup.20
and R.sup.21 are independently selected from the group consisting
of alkyl, substituted aryl and heteroaryl. In one embodiment,
R.sup.20 is methyl and R.sup.21 is methyl. Preferably, in this last
embodiment, R.sup.7 is hydrogen, methyl, ethyl, benzyl,
--C(CH.sub.3).dbd.CH.sub.2, --CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00038## [0338] where V is O or CH.sub.2.
[0339] Most preferably, R.sup.7 is hydrogen.
[0340] In another embodiment of compounds of Formulae (IX) or (X),
R.sup.20 and R.sup.21 together with the carbon atom to which they
are attached form a cycloalkyl or substituted cycloalkyl ring. In
one embodiment, R.sup.20 and R.sup.21 together with the carbon atom
to which they are attached form a cyclohexyl ring. Preferably, in
this last embodiment, R.sup.7 is hydrogen, methyl, ethyl, benzyl,
--C(CH.sub.3).dbd.CH.sub.2, --CH.sub.2C(O)N(CH.sub.3).sub.2,
##STR00039##
[0341] where V is O or CH.sub.2.
[0342] Most preferably, R.sup.7 is hydrogen.
[0343] In one embodiment, the compounds of the invention have the
structure of Formula
##STR00040##
(III):
[0344] In one embodiment of the compounds of Formula (III), n is 1,
R.sup.1 is hydrogen and R.sup.2 is arylalkyl. Preferably, R.sup.2
is benzyl. In another embodiment of the compounds of Formula (III),
n is 0 and R.sup.1 is R.sup.25OC(O)--. Preferably, R.sup.25 is
alkyl or substituted alkyl. More preferably, R.sup.25 is ethyl. In
still another embodiment of the compounds of Formula (III),
R.sup.22 and R.sup.23 are hydrogen. In still another embodiment,
R.sup.22 and R.sup.23 are alkyl or substituted alkyl. Preferably,
R.sup.22 and R.sup.23 are methyl.
[0345] In a preferred embodiment, the compounds of Formula (III)
have the structure of Formula (XI):
##STR00041##
[0346] In one embodiment of the compounds of Formula (XI), n is 1,
X is NH, Y is O, R.sup.1 is hydrogen, R.sup.2 is benzyl, R.sup.22
is methyl and R.sup.23 are methyl. In another embodiment, n is 0, Y
is O, R.sup.1 is R.sup.25OC(O)--, R.sup.25 is ethyl, R.sup.22 is
hydrogen and R.sup.23 is hydrogen.
[0347] In another embodiment, the compounds of Formula (III) have
the structure of Formula (XII):
##STR00042##
[0348] In one embodiment of the compounds of Formula (XII), n is 1,
X is NH, Y is O, R.sup.1 is hydrogen, R.sup.2 is benzyl, R.sup.22
is methyl and R.sup.23 are methyl. In another embodiment, n is 0, Y
is O, R.sup.1 is R.sup.25OC(O)--, R.sup.25 is ethyl, R.sup.22 is
hydrogen and R.sup.23 is hydrogen.
[0349] The instant invention also comprises a GABA analog
derivative, M-G, for administration to a patient in need of
therapy, wherein M is a promoiety and G is derived from a GABA
analog, H-G (where H is hydrogen). The promoiety M, once cleaved
from G, and any metabolite thereof, exhibits a carcinogenically
toxic dose (TD.sub.50) in rats of greater than 0.2 mmol/kg/day.
Further, the promoiety M is cleaved from G at a sufficient rate in
vivo, upon colonic administration to rats, to produce: [0350] (i) a
maximum concentration of H-G in plasma (C.sub.max) of at least 120%
of the C.sub.max of H-G in plasma achieved by colonically
administering an equimolar dose of H-G; and [0351] (ii) an AUC that
is at least 120% of the AUC achieved by colonically administering
an equimolar dose of H-G.
[0352] Preferably, M-G has the structure of Formula (XIV):
##STR00043##
or a pharmaceutically acceptable salt, hydrate or solvate thereof,
wherein:
[0353] M is a promoiety;
[0354] Y is O or S;
[0355] R is hydrogen, or R and R.sup.6 together with the atoms to
which they are attached form an azetidine, substituted azetidine,
pyrrolidine or substituted pyrrolidine ring;
[0356] R.sup.3 and R.sup.6 are independently selected from the
group consisting of hydrogen, alkyl, substituted alkyl, aryl,
substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl,
substituted cycloalkyl, cycloheteroalkyl, substituted
cycloheteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl;
[0357] R.sup.4 and R.sup.5 are independently selected from the
group consisting of hydrogen, alkyl, substituted alkyl, acyl,
substituted acyl, aryl, substituted aryl, arylalkyl, substituted
arylalkyl, cycloalkyl, substituted cycloalkyl, cycloheteroalkyl,
substituted cycloheteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl or optionally,
R.sup.4 and R.sup.5 together with the carbon atom to which they are
attached form a cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl or bridged
cycloalkyl ring; and
[0358] R.sup.7 is selected from the group consisting of hydrogen,
alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl,
substituted arylalkyl, cycloalkyl, substituted cycloalkyl,
cycloheteroalkyl, substituted cycloheteroalkyl, heteroalkyl,
substituted heteroalkyl, heteroaryl, substituted heteroaryl,
heteroarylalkyl and substituted heteroarylalkyl.
[0359] In a preferred embodiment, M has the structure of Formula
(XV):
##STR00044##
[0360] wherein:
[0361] n, X, R.sup.1 and R.sup.2 are as previously defined
[0362] In one embodiment, M-G include compounds wherein H-G, once
cleaved from M, is substantially free of any lactam having the
structure of Formula (XVI):
##STR00045##
[0363] wherein R is hydrogen and R.sup.3, R.sup.4, R.sup.5 and
R.sup.6 are as previously defined
[0364] Preferably, promoiety M or any metabolite formed from M does
not form formaldehyde or pivalic acid upon cleavage of G-M. In one
embodiment, the promoiety M is cleaved from G at a sufficient rate
in vivo, upon colonic administration to rats, to produce a
C.sub.max of H-G in plasma of at least 200%, and most preferably at
least 1000%, of the C.sub.max of H-G in plasma achieved by
colonically administering an equimolar dose of H-G. Preferably, the
promoiety M is cleaved from G at a sufficient rate in vivo, upon
colonic administration to rats, to produce an AUC of H-G in plasma
of at least 200%, and most preferably at least 500%, of the AUC of
H-G in plasma achieved by colonically administering an equimolar
dose of H-G. In another embodiment, the promoiety M is cleaved from
H-G at a sufficient rate in vivo, following oral administration to
dogs (e.g., using an osmotic mini-pump device) at a dose of about
60 .mu.mol equivalent of H-G per kg, to produce a plasma
concentration of H-G at 12 hours post dosing of at least 200% of
the plasma concentration of H-G achieved from an equimolar dose of
H-G following the same mode of administration.
3.3 Synthesis of the Compounds of the Invention
[0365] The compounds of the invention may be obtained via the
synthetic methods illustrated in Schemes 1-17. Those of skill in
the art will appreciate that a preferred synthetic route to the
compounds of the invention consists of attaching promoieties to
GABA analogs. Numerous methods have been described in the art for
the synthesis of GABA analogs (See, e.g., Satzinger et al., U.S.
Pat. No. 4,024,175; Silverman et al., U.S. Pat. No. 5,563,175;
Horwell et al., U.S. Pat. No. 6,020,370; Silverman et al., U.S.
Pat. No. 6,028,214; Horwell et al., U.S. Pat. No. 6,103,932;
Silverman et al., U.S. Pat. No. 6,117,906; Silverman, International
Publication No. WO 92/09560; Silverman et al., International
Publication No. WO 93/23383; Horwell et al., International
Publication No. WO 97/29101, Horwell et al., International
Publication No. WO 97/33858; Horwell et al., International
Publication No. WO 97/33859; Bryans et al., International
Publication No. WO 98/17627; Guglietta et al., International
Publication No. WO 99/08671; Bryans et al., International
Publication No. WO 99/21824; Bryans et al., International
Publication No. WO 99/31057; Belliotti et al., International
Publication No. WO 99/31074; Bryans et al., International
Publication No. WO 99/31075; Bryans et al., International
Publication No. WO 99/61424; Bryans et al., International
Publication No. WO 00/15611; Bryans, International Publication No.
WO 00/31020; and Bryans et al., International Publication No. WO
00/50027). Other methods are known in the art for synthesizing GABA
analogs, which are readily accessible to the skilled artisan. The
promoieties described herein, are known in the art and may be
prepared and attached to GABA analogs by established procedures
(See e.g., Green et al., "Protective Groups in Organic Chemistry",
(Wiley, 2.sup.nd ed. 1991); Harrison et al., "Compendium of
Synthetic Organic Methods", Vols. 1-8 (John Wiley and Sons,
1971-1996); "Beilstein Handbook of Organic Chemistry," Beilstein
Institute of Organic Chemistry, Frankfurt, Germany; Feiser et al.,
"Reagents for Organic Synthesis," Volumes 1-17, Wiley Interscience;
Trost et al., "Comprehensive Organic Synthesis," Pergamon Press,
1991; "Theilheimer's Synthetic Methods of Organic Chemistry,"
Volumes 1-45, Karger, 1991; March, "Advanced Organic Chemistry,"
Wiley Interscience, 1991; Larock "Comprehensive Organic
Transformations," VCH Publishers, 1989; Paquette, "Encyclopedia of
Reagents for Organic Synthesis," John Wiley & Sons, 1995,
Bodanzsky, "Principles of Peptide Synthesis," Springer Verlag,
1984; Bodanzsky, "Practice of Peptide Synthesis," Springer Verlag,
1984).
[0366] Accordingly, starting materials useful for preparing
compounds of the invention and intermediates thereof are
commercially available or can be prepared by well-known synthetic
methods. Other methods for synthesis of the prodrugs described
herein are either described in the art or will be readily apparent
to the skilled artisan in view of the references provided above and
may be used to synthesize the compounds of the invention.
Accordingly, the methods presented in the Schemes herein are
illustrative rather than comprehensive.
[0367] In any of the Schemes below, after the amino group of a GABA
analog has been functionalized with a promoiety or other protecting
group, the carboxylic acid group may be converted to an ester or
thioester by many synthetic methods, which are well-known to the
skilled artisan. In one preferred embodiment, GABA analogs may be
reacted with an alcohol or thiol in the presence of a coupling
reagent (e.g., carbodiimide and dimethylaminopyridine) to provide
the ester. In another preferred embodiment, GABA analogs may be
reacted with an alkyl halide in the presence of base to yield the
ester. Other methods for converting GABA analogs to esters or
thioesters are well within the purview of the skilled artisan in
view of the references provided herein.
##STR00046##
[0368] As illustrated above in Scheme 1, carboxylic acids can be
directly coupled to the terminal amino (or hydroxyl) group of GABA
analog derivatives (6) to provide adducts (7). Reagents for
effecting this reaction are well known to the skilled artisan and
include, but are not limited to, carbodiimides, aminium salts,
phosphonium salts, etc. Alternatively, reaction of carboxylic acid
derivatives such as acyl chlorides, symmetrical anhydrides or mixed
anhydrides with GABA analogs (6) in the presence of base (e.g.,
hydroxide, tertiary amines, etc.) may be used to synthesize
(7).
##STR00047##
[0369] As illustrated in Scheme 2, GABA analog derivatives (6) may
be converted to carbamates (8) by treatment with various carbonic
acid derivatives in the presence of base (e.g., hydroxide, tertiary
amines, etc.). Alternatively, the well-known addition of alcohols
to isocyanates (9) or (10) may be used to synthesize (8).
##STR00048##
[0370] As illustrated in Scheme 3, GABA analog derivatives (6) may
be converted to thioamides (11) by reaction with thioacids in the
presence of coupling agents. Reagents for effecting this reaction
are well known to the skilled artisan and include, but are not
limited to, carbodiimides, aminium salts, phosphonium salts, etc.
Alternatively, reaction of thio acid derivatives such as thioacyl
chlorides, symmetrical anhydrides or mixed anhydrides with (6) in
the presence of base (e.g., hydroxide, tertiary amines, etc.) may
be used to synthesize thioamides (11). In yet another method,
amides (7) may be converted to thioamides (11) by heating in the
presence of phosphorus pentasulfide (when n=0).
[0371] Thiocarbamates (12) and (13) may be synthesized from the
reaction of the corresponding thiocarbonate derivatives (i.e., P=P,
Q=S and P=S Q=O, respectively) where W is chloride, imidazolyl or
4-nitrophenoxy with GABA analog derivatives (6) in the presence of
base. Thiocarbamate (13) may also be formed by reaction of a thiol
with isocyanates (9) or (10). Dithiocarbamate (14) (P=S, Q=S) may
be made by reaction of GABA analog derivatives (6) with the
dithiocarbonate derivative (i.e., P and Q=S) where W is chloride,
imidazolyl or 4-nitrophenoxy in the presence of base (see Scheme
4).
##STR00049##
[0372] One method for synthesis of compounds of Formula (IV) is
illustrated in Scheme 5.
##STR00050##
[0373] Chloroformate (15) is treated with an aromatic leaving group
such asp-nitrophenol in the presence of base to provide
p-nitrophenylcarbonate (16). Halide interchange provides iodide
(17), which is reacted with a metal or tetraalkylammonium salt of a
carboxylic acid to afford compound (18). Treatment of (18) with
GABA analog derivative (19), optionally in the presence of
trimethylsilyl chloride, affords a compound of Formula (IV).
Methods for making related acyloxyalkyl carbamate compounds have
been described in the art (Alexander, U.S. Pat. No. 4,760,057;
Alexander, U.S. Pat. No. 4,916,230; Alexander, U.S. Pat. No.
5,466,811; Alexander, U.S. Pat. No. 5,684,018).
[0374] Alternatively compounds of Formula (IV) can be prepared from
carbonate (18) in a stepwise fashion as illustrated in Scheme 6.
Here reaction of (18) with an ao-amino acid (20), optionally
protected as an ester, affords intermediate (21) which upon
deprotection (if necessary) provides compound (22), which is then
coupled to GABA analog (23) using standard peptide coupling
reagents well known in the art.
##STR00051##
[0375] Another method for synthesis of compounds of Formula (IV)
proceeds via carbonylation of GABA analog derivative (19) to an
intermediate carbamic acid species, which is captured by an in situ
alkylation reaction in an adaptation of the methods disclosed in
the art (Butcher, Synlett, 1994, 825-6; Ferres et al., U.S. Pat.
No. 4,036,829). Carbon dioxide gas is bubbled into a solution
containing (19) and a base (e.g., Cs.sub.2CO.sub.3,
Ag.sub.2CO.sub.3 or AgO) in a solvent such as DMF or NMP. The
activated halide is added, optionally in the presence of iodide ion
as a catalyst, and the carbonylation continued until the reaction
is completed. This method is illustrated in Scheme 7 for the
preparation of compounds of Formula (IV) from halide (24).
##STR00052##
[0376] Alternatively compounds of Formula (IV) can be prepared in a
stepwise fashion as illustrated in Scheme 8. Carbonylation and
alkylation of carboxyl protected .alpha.-amino acid (20) provides
intermediate (21), which upon deprotection is coupled to GABA
analog (23) as previously described in Scheme 6.
##STR00053##
[0377] Yet another method for synthesis of compounds of Formula
(IV) relies upon oxidation of ketocarbamate derivatives of GABA
analogs (Gallop et al., U.S. Pat. No. 6,927,036 entitled "Methods
for Synthesis of Prodrugs from 1-Acyl-Alkyl Derivatives and
Compositions Thereof"). As illustrated in Scheme 9, oxidation of
ketocarbamate (25) affords compounds of Formula (IV). Preferred
solvents include, but are not limited to, t-butanol, diethylether,
acetic acid, hexane, dichloroethane, dichloromethane, ethyl
acetate, acetonitrile, methanol, chloroform and water. Generally,
the oxidant may be an organism (e.g., yeast or bacteria), or a
chemical reagent (e.g., an enzyme or peroxide). Preferred oxidants
include those, which have been successfully used in Baeyer-Villager
oxidations of ketones to esters or lactones (Strukul, Angnew. Chem.
Int. Ed., 1998, 37, 1198; Renz et al., Eur. J. Org. Chem. 1999,
737; Beller et al., in "Transition Metals in Organic Synthesis"
Chapter 2, Wiley VCH; Stewart, Current Organic Chemistry, 1998, 2,
195; Kayser et al., Synlett, 1999, 1, 153).
##STR00054##
[0378] Other compounds of this invention may be amenable to
synthesis from the appropriate ketocarbamate derivative via this
Baeyer-Villiger type oxidation, provided that they do not contain
chemical functionality susceptible to decomposition or other
transformation under conditions of the reaction.
[0379] Ketocarbamates (25) may be prepared from the corresponding
.alpha.-hydroxyketone compounds (26) either directly, via reaction
with isocyanate (9), or by first converting the
.alpha.-hydroxyketone compound to a haloformate or activated
carbonate intermediate (27) and subsequently reacting with compound
(19), as illustrated in Scheme 10.
##STR00055##
[0380] Alternatively ketocarbamate (25) can be prepared in a
stepwise manner via the .alpha.-amino acid carbamate (28) as
illustrated in Scheme 11, following the coupling methodologies
described above.
##STR00056##
[0381] Note that one method for preparation of isocyanate
derivatives of GABA analogs (i.e., compounds (9)) used in Scheme 10
above begins with the appropriate six-membered anhydride (29) as
illustrated in Scheme 12. The anhydride ring is opened by reaction
with an alcohol or thiol nucleophile to afford carboxylic acid
(30). This compound is converted to the intermediate acyl azide in
either a 2-step sequence (i.e., first activation of the carboxyl
group as a mixed anhydride, acyl halide or synthetic equivalent and
then displacement with azide) or directly (e.g., by treatment with
Ph.sub.2P(O)N.sub.3). Curtius rearrangement of the acyl azide
intermediate by thermolysis in an appropriate solvent (e.g.,
toluene) at a temperature between 0.degree. C. to 120.degree. C.
affords isocyanate (9). Optionally, the isocyanate is not isolated
but rather is generated in situ and quenched by reaction with
.alpha.-hydroxyketone (26) to afford the desired product (25).
##STR00057##
[0382] One method for synthesis of oxodioxolenylmethyl carbamate
prodrugs (36) is disclosed in Scheme 13. Hydroxyketone (31) is
treated with phosgene or carbonyldiimidazole in the presence of
base to yield cyclic carbonate (32). Free radical bromination with
N-bromosuccinimide and azoisobutryonitrile provides bromide (33),
which is converted to alcohol (34). Alcohol (34) is transformed to
dicarbonate (35) by reaction with 4-nitrophenyl chloroformate,
which is then reacted with GABA analog derivatives (19) to provide
prodrugs (36). Alternatively, reaction of compound (34) with
isocyanate (9) provides compound (36), where n is 0.
##STR00058##
[0383] Prodrugs (41) may be synthesized by the method disclosed in
Scheme 14. Carboxylic acid (37) is coupled to alcohol (38) (e.g.,
dicylohexylcarbodiimide and pyridine) to provide ester (39). Ester
(39) is converted to activated carbonate (40) by reaction with
4-nitrophenyl chloroformate, which is then reacted with GABA analog
derivative (19) to provide prodrug (41).
##STR00059##
[0384] Enamine prodrugs such as (43) may be synthesized simply by
reacting activated carbonyl compounds (42) with GABA analog
derivatives (19) (where R.sup.16=H), optionally in the presence of
a secondary amine as catalyst, under dehydrating conditions as
shown in Scheme 15.
##STR00060##
[0385] Compounds (III) may be synthesized by the route illustrated
in Scheme 16. Reaction of GABA analog (23) with an
.alpha.-activated ester derivative (44) provides amino ester (45).
The amino group of (45) is blocked by acylation to yield (46)
(e.g., using the methods described above) and the free acid is
esterified under standard conditions to yield the diester (47).
Dieckman condensation followed by decarboxylation yields ketone
(48). Peroxy acid oxidation then provides lactone (III).
##STR00061##
[0386] Imine prodrugs (II) may be synthesized as depicted in Scheme
17 by treating ketones or ketone equivalents (49) with GABA analog
derivatives (50) under dehydrating conditions.
##STR00062##
[0387] Phosphorus prodrugs may be synthesized by conventional
methods-known in the art. Similarly, prodrugs with S--N bond may be
synthesized by using procedures described in the art.
3.4 Therapeutic Uses of the Compounds of the Invention
[0388] In accordance with the invention, a compound and/or
composition of the invention is administered to a patient,
preferably a human, suffering from epilepsy, depression, anxiety,
psychosis, faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain (especially, neuropathic
pain and muscular and skeletal pain), inflammatory disease (i.e.,
arthritis), insomnia, gastrointestinal disorders or ethanol
withdrawal syndrome. Further, in certain embodiments, the compounds
and/or compositions of the invention are administered to a patient,
preferably a human, as a preventative measure against various
diseases or disorders. Thus, the compounds and/or compositions of
the invention may be administered as a preventative measure to a
patient having a predisposition for epilepsy, depression, anxiety,
psychosis, faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain (especially, neuropathic
pain and muscular and skeletal pain), inflammatory disease (i.e.,
arthritis), insomnia, gastrointestinal disorders and ethanol
withdrawal syndrome. Accordingly, the compounds and/or compositions
of the invention may be used for the prevention of one disease or
disorder and concurrently treating another (e.g., prevention of
psychosis while treating gastrointestinal disorders; prevention of
neuropathic pain while treating ethanol withdrawal syndrome).
[0389] The suitability of the compounds and/or compositions of the
invention in treating epilepsy, depression, anxiety, psychosis,
faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain (especially neuropathic
pain and muscular and skeletal pain), inflammatory disease (i.e.,
arthritis), insomnia, gastrointestinal disorders and ethanol
withdrawal syndrome may be determined by methods described in the
art (See, e.g., Satzinger et al., U.S. Pat. No. 4,024,175;
Satzinger et al., U.S. Pat. No. 4,087,544; Woodruff, U.S. Pat. No.
5,084,169; Silverman et al., U.S. Pat. No. 5,563,175; Singh, U.S.
Pat. No. 6,001,876; Horwell et al., U.S. Pat. No. 6,020,370;
Silverman et al., U.S. Pat. No. 6,028,214; Horwell et al., U.S.
Pat. No. 6,103,932; Silverman et al., U.S. Pat. No. 6,117,906;
Silverman, International Publication No. WO 92/09560; Silverman et
al., International Publication No. WO 93/23383; Horwell et al.,
International Publication No. WO 97/29101, Horwell et al.,
International Publication No. WO 97/33858; Horwell et al.,
International Publication No. WO 97/33859; Bryans et al.,
International Publication No. WO 98/17627; Guglietta et al.,
International Publication No. WO 99/08671; Bryans et al.,
International Publication No. WO 99/21824; Bryans et al.,
International Publication No. WO 99/31057; Magnus-Miller et al.,
International Publication No. WO 99/37296; Bryans et al.,
International Publication No. WO 99/31075; Bryans et al.,
International Publication No. WO 99/61424; Pande, International
Publication No. WO 00/23067; Bryans, International Publication No.
WO 00/31020; Bryans et al., International Publication No. WO
00/50027; and Bryans et al, International Publication No. WO
02/00209). The compounds and/or compositions of the invention may
be used to treat or prevent epilepsy, depression, anxiety,
psychosis, faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain (especially neuropathic
pain and muscular and skeletal pain), inflammatory disease (i.e.,
arthritis), insomnia, gastrointestinal disorders and ethanol
withdrawal syndrome by procedures described in the art (see
references above). Thus, it is well with the capability of those of
skill in the art to assay and use the compounds and/or compositions
of the invention to treat or prevent epilepsy, depression, anxiety,
psychosis, faintness attacks, hypokinesia, cranial disorders,
neurodegenerative disorders, panic, pain (especially, neuropathic
pain and muscular and skeletal pain), inflammatory disease (i.e.,
arthritis), insomnia, gastrointestinal disorders and ethanol
withdrawal syndrome.
3.5 Therapeutic/Prophylactic Administration
[0390] The compounds and/or compositions of the invention may be
advantageously used in human medicine. As previously described in
Section 4.4 above, compounds and/or compositions of the invention
are useful for the treatment or prevention of epilepsy, depression,
anxiety, psychosis, faintness attacks, hypokinesia, cranial
disorders, neurodegenerative disorders, panic, pain (especially,
neuropathic pain and muscular and skeletal pain), inflammatory
disease (i.e., arthritis), insomnia, gastrointestinal disorders or
ethanol withdrawal syndrome.
[0391] When used to treat or prevent the above disease or disorders
compounds and/or compositions of the invention may be administered
or applied singly, in combination with other agents. The compounds
and/or compositions of the invention may also be administered or
applied singly, in combination with other pharmaceutically active
agents, including other compounds of the invention.
[0392] The current invention provides methods of treatment and
prophylaxis by administration to a patient of a therapeutically
effective amount of a composition or compound of the invention. The
patient may be an animal, is more preferably a mammal, and most
preferably a human.
[0393] The present compounds and/or compositions of the invention,
which comprise one or more compounds of the invention, are
preferably administered orally. The compounds and/or compositions
of the invention may also be administered by any other convenient
route, for example, by infusion or bolus injection, by absorption
through epithelial or mucocutaneous linings (e.g., oral mucosa,
rectal and intestinal mucosa, etc.). Administration can be systemic
or local. Various delivery systems are known, (e.g., encapsulation
in liposomes, microparticles, microcapsules, capsules, etc.) that
can be used to administer a compound and/or composition of the
invention. Methods of administration include, but are not limited
to, intradermal, intramuscular, intraperitoneal, intravenous,
subcutaneous, intranasal, epidural, oral, sublingual, intranasal,
intracerebral, intravaginal, transdermal, rectally, by inhalation,
or topically, particularly to the ears, nose, eyes, or skin.
[0394] In particularly preferred embodiments, the compounds and/or
compositions of the invention can be delivered via sustained
release systems, preferably oral sustained release systems. In one
embodiment, a pump may be used (see Langer, supra; Sefton, 1987,
CRC Crit Ref Biomed Eng. 14:201; Saudek et al., 1989, N. Engl. J
Med. 321:574).
[0395] In another embodiment, polymeric materials can be used (see
"Medical Applications of Controlled Release," Langer and Wise
(eds.), CRC Pres., Boca Raton, Fla. (1974); "Controlled Drug
Bioavailability," Drug Product Design and Performance, Smolen and
Ball (eds.), Wiley, New York (1984); Ranger and Peppas, 1983, J
Macromol. Sci. Rev. Macromol Chem. 23:61; see also Levy et al.,
1985, Science 228: 190; During et al., 1989, Ann. Neurol. 25:351;
Howard et al, 1989, J. Neurosurg. 71:105). In a preferred
embodiment, polymeric materials are used for oral sustained release
delivery. Preferred polymers include sodium carboxymethylcellulose,
hydroxypropylcellulose, hydroxypropylmethylcellulose and
hydroxyethylcellulose (most preferred,
hydroxypropylmethylcellulose). Other preferred cellulose ethers
have been described (Alderman, Int. J. Pharm. Tech. & Prod.
Mfr., 1984, 5(3) 1-9). Factors affecting drug release are well
known to the skilled artisan and have been described in the art
(Bamba et al., Int. J. Pharm., 1979, 2, 307).
[0396] In another embodiment, enteric-coated preparations can be
used for oral sustained release administration. Preferred coating
materials include polymers with a pH-dependent solubility (i.e.,
pH-controlled release), polymers with a slow or pH-dependent rate
of swelling, dissolution or erosion (i.e., time-controlled
release), polymers that are degraded by enzymes (i.e.,
enzyme-controlled release) and polymers that form firm layers that
are destroyed by an increase in pressure (i.e., pressure-controlled
release).
[0397] In still another embodiment, osmotic delivery systems are
used for oral sustained release administration (Verma et al., Drug
Dev. Ind. Pharm., 2000, 26:695-708). In a preferred embodiment,
OROS.TM. osmotic devices are used for oral sustained release
delivery devices (Theeuwes et al., U.S. Pat. No. 3,845,770;
Theeuwes et al., U.S. Pat. No. 3,916,899).
[0398] In yet another embodiment, a controlled-release system can
be placed in proximity of the target of the compounds and/or
composition of the invention, thus requiring only a fraction of the
systemic dose (see, e.g., Goodson, in "Medical Applications of
Controlled Release," supra, vol. 2, pp. 115-138 (1984)). Other
controlled-release systems discussed in Langer, 1990, Science
249:1527-1533 may also be used.
[0399] The compounds and/or compositions of the invention
preferably provide GABA analogs (e.g., gabapentin and pregablin)
upon in vivo administration to a patient. While not wishing to
bound by theory, the promoiety or promoieties of the compounds
and/or compositions of the invention may be cleaved either
chemically and/or enzymatically. One or more enzymes present in the
stomach, intestinal lumen, intestinal tissue, blood, liver, brain
or any other suitable tissue of a mammal may enzymatically cleave
the promoiety or promoieties of the compounds and/or compositions
of the invention. The mechanism of cleavage is not important to the
current invention. Preferably, GABA analogs formed by cleavage of
prodrugs from the compounds of the invention do not contain
substantial quantities of lactam contaminant (preferably, less than
0.5% by weight, more preferably, less than 0.2% by weight, most
preferably less than 0.1% by weight). The extent of release of
lactam contaminant from the prodrugs of this invention may be
assessed using the standard in vitro analytical methods.
[0400] While not wishing to bound by theory, the promoiety or
promoieties of the compounds and/or compositions of the invention
may be cleaved prior to absorption by the gastrointestinal tract
(e.g., within the stomach or intestinal lumen) and/or after
absorption by the gastrointestinal tract (e.g., in intestinal
tissue, blood, liver or other suitable tissue of a mammal). If the
promoiety or promoieties of the compounds of the invention are
cleaved prior to absorption by the gastrointestinal tract, the
resulting GABA analogs may be absorbed into the systemic
circulation conventionally (e.g. via the large neutral amino acid
transporter located in the small intestine). If the promoiety or
promoieties of the compounds of the invention are cleaved after
absorption by the gastrointestinal tract, these GABA analog
prodrugs may have the opportunity to be absorbed into the systemic
circulation either by passive diffusion, active transport or by
both passive and active processes.
[0401] If the promoiety or promoieties of the compounds of the
invention are cleaved after absorption by the gastrointestinal
tract, these GABA analog prodrugs may have the opportunity to be
absorbed into the systemic circulation from the large intestine. In
this situation, the compounds and/or compositions of the invention
are preferably administered as sustained release systems. In a
preferred embodiment, the compounds and/or compositions of the
invention are delivered by oral sustained release administration.
Preferably, in this embodiment, the compounds and/or compositions
of the invention are administered twice per day (more preferably,
once per day).
3.6 Compositions of the Invention
[0402] The present compositions contain a therapeutically effective
amount of one or more compounds of the invention, preferably in
purified form, together with a suitable amount of a
pharmaceutically acceptable vehicle, to provide the form for proper
administration to a patient.
[0403] When administered to a patient, the compounds of the
invention and pharmaceutically acceptable vehicles are preferably
sterile. Water is a preferred vehicle when a compound of the
invention is administered intravenously. Saline solutions and
aqueous dextrose and glycerol solutions can also be employed as
liquid vehicles, particularly for injectable solutions. Suitable
pharmaceutical vehicles also include excipients such as starch,
glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk,
silica gel, sodium stearate, glycerol monostearate, talc, sodium
chloride, dried skim milk, glycerol, propylene, glycol, water,
ethanol and the like. The present compositions, if desired, can
also contain minor amounts of wetting or emulsifying agents, or pH
buffering agents. In addition, auxiliary, stabilizing, thickening,
lubricating and coloring agents may be used.
[0404] In one embodiment, the compositions of the invention are
free of lactam side products formed by intramolecular cyclization.
In a preferred embodiment, the compositions of the invention are
stable to extended storage (preferably, greater than one year)
without substantial lactam formation (preferably, less than 0.5%
lactam by weight, more preferably, less than 0.2% lactam by weight,
most preferably, less than 0.1% lactam by weight).
[0405] Pharmaceutical compositions comprising a compound of the
invention may be manufactured by means of conventional mixing,
dissolving, granulating, dragee-making, levigating, emulsifying,
encapsulating, entrapping or lyophilizing processes. Pharmaceutical
compositions may be formulated in conventional manner using one or
more physiologically acceptable carriers, diluents, excipients or
auxiliaries, which facilitate processing of compounds of the
invention into preparations which can be used pharmaceutically.
Proper formulation is dependent upon the route of administration
chosen.
[0406] The present compositions can take the form of solutions,
suspensions, emulsion, tablets, pills, pellets, capsules, capsules
containing liquids, powders, sustained-release formulations,
suppositories, emulsions, aerosols, sprays, suspensions, or any
other form suitable for use. In one embodiment, the
pharmaceutically acceptable vehicle is a capsule (see e.g.,
Grosswald et al., U.S. Pat. No. 5,698,155). Other examples of
suitable pharmaceutical vehicles have been described in the art
(see Remington's Pharmaceutical Sciences, Philadelphia College of
Pharmacy and Science, 17th Edition, 1985). Preferred compositions
of the invention are formulated for oral delivery, particularly for
oral sustained release administration.
[0407] Compositions for oral delivery may be in the form of
tablets, lozenges, aqueous or oily suspensions, granules, powders,
emulsions, capsules, syrups, or elixirs, for example. Orally
administered compositions may contain one or more optional agents,
for example, sweetening agents such as fructose, aspartame or
saccharin, flavoring agents such as peppermint, oil of wintergreen,
or cherry coloring agents and preserving agents, to provide a
pharmaceutically palatable preparation. Moreover, where in tablet
or pill form, the compositions may be coated to delay
disintegration and absorption in the gastrointestinal tract,
thereby providing a sustained action over an extended period of
time. Selectively permeable membranes surrounding an osmotically
active driving compound are also suitable for orally administered
compounds and compositions of the invention. In these later
platforms, fluid from the environment surrounding the capsule is
imbibed by the driving compound, which swells to displace the agent
or agent composition through an aperture. These delivery platforms
can provide an essentially zero order delivery profile as opposed
to the spiked profiles of immediate release formulations. A time
delay material such as glycerol monostearate or glycerol stearate
may also be used. Oral compositions can include standard vehicles
such as mannitol, lactose, starch, magnesium stearate, sodium
saccharine, cellulose, magnesium carbonate, etc. Such vehicles are
preferably of pharmaceutical grade.
[0408] For oral liquid preparations such as, for example,
suspensions, elixirs and solutions, suitable carriers, excipients
or diluents include water, saline, alkyleneglycols (e.g., propylene
glycol), polyalkylene glycols (e.g., polyethylene glycol) oils,
alcohols, slightly acidic buffers between pH 4 and pH 6 (e.g.,
acetate, citrate, ascorbate at between about 5 mM to about 50 mM),
etc. Additionally, flavoring agents, preservatives, coloring
agents, bile salts, acylcarnitines and the like may be added.
[0409] Compositions for administration via other routes may also be
contemplated. For buccal administration, the compositions may take
the form of tablets, lozenges, etc. formulated in conventional
manner. Liquid drug formulations suitable for use with nebulizers
and liquid spray devices and EHD aerosol devices will typically
include a compound of the invention with a pharmaceutically
acceptable vehicle. Preferably, the pharmaceutically acceptable
vehicle is a liquid such as alcohol, water, polyethylene glycol or
a perfluorocarbon. Optionally, another material may be added to
alter the aerosol properties of the solution or suspension of
compounds of the invention. Preferably, this material is liquid
such as an alcohol, glycol, polyglycol or a fatty acid. Other
methods of formulating liquid drug solutions or suspension suitable
for use in aerosol devices are known to those of skill in the art
(see, e.g., Biesalski, U.S. Pat. No. 5,112,598; Biesalski, U.S.
Pat. No. 5,556,611). A compound of the invention may also be
formulated in rectal or vaginal compositions such as suppositories
or retention enemas, e.g., containing conventional suppository
bases such as cocoa butter or other glycerides. In addition to the
formulations described previously, a compound of the invention may
also be formulated as a depot preparation. Such long acting
formulations may be administered by implantation (for example
subcutaneously or intramuscularly) or by intramuscular injection.
Thus, for example, a compound of the invention may be formulated
with suitable polymeric or hydrophobic materials (for example as an
emulsion in an acceptable oil) or ion exchange resins, or as
sparingly soluble derivatives, for example, as a sparingly soluble
salt.
[0410] When a compound of the invention is acidic, it may be
included in any of the above-described formulations as the free
acid, a pharmaceutically acceptable salt, a solvate or hydrate.
[0411] Pharmaceutically acceptable salts substantially retain the
activity of the free acid, may be prepared by reaction with bases
and tend to be more soluble in aqueous and other protic solvents
than the corresponding free acid form.
3.7 Methods of Use and Doses
[0412] A compound of the invention, or compositions thereof, will
generally be used in an amount effective to achieve the intended
purpose. For use to treat or prevent diseases or disorders such as
epilepsy, depression, anxiety, psychosis, faintness attacks,
hypokinesia, cranial disorders, neurodegenerative disorders, panic,
pain (especially neuropathic pain and muscular and skeletal pain),
inflammatory disease (i.e., arthritis), insomnia, gastrointestinal
disorders or ethanol withdrawal syndrome the compounds of the
invention or compositions thereof, are administered or applied in a
therapeutically effective amount.
[0413] The amount of a compound of the invention that will be
effective in the treatment of a particular disorder or condition
disclosed herein will depend on the nature of the disorder or
condition, and can be determined by standard clinical techniques
known in the art as previously described. In addition, in vitro or
in vivo assays may optionally be employed to help identify optimal
dosage ranges. The amount of a compound of the invention
administered will, of course, be dependent on, among other factors,
the subject being treated, the weight of the subject, the severity
of the affliction, the manner of administration and the judgment of
the prescribing physician.
[0414] For example, the dosage may be delivered in a pharmaceutical
composition by a single administration, by multiple applications or
controlled release. In a preferred embodiment, the compounds of the
invention are delivered by oral sustained release administration.
Preferably, in this embodiment, the compounds of the invention are
administered twice per day (more preferably, once per day). Dosing
may be repeated intermittently, may be provided alone or in
combination with other drugs and may continue as long as required
for effective treatment of the disease state or disorder.
[0415] Suitable dosage ranges for oral administration are dependent
on the potency of the parent GABA analog drug, but are generally
about 0.001 mg to about 200 mg of a compound of the invention per
kilogram body weight. When the GABA analog is gabapentin, typical
daily doses of the parent drug in adult patients are 900 mg/day to
3600 mg/day and the dose of gabapentin prodrug may be adjusted to
provide an equivalent molar quantity of gabapentin. Other GABA
analogs may be more potent than gabapentin (e.g., pregabalin), and
lower doses may be appropriate for both the parent drug and any
prodrug (measured on an equivalent molar basis). Dosage ranges may
be readily determined by methods known to the skilled artisan.
[0416] The compounds of the invention are preferably assayed in
vitro and in vivo, for the desired therapeutic or prophylactic
activity, prior to use in humans. For example, in vitro assays can
be used to determine whether administration of a specific compound
of the invention or a combination of compounds of the invention is
preferred for reducing convulsion. The compounds of the invention
may also be demonstrated to be effective and safe using animal
model systems.
[0417] Preferably, a therapeutically effective dose of a compound
of the invention described herein will provide therapeutic benefit
without causing substantial toxicity. Toxicity of compounds of the
invention may be determined using standard pharmaceutical
procedures and may be readily ascertained by the skilled artisan.
The dose ratio between toxic and therapeutic effect is the
therapeutic index. A compound of the invention will preferably
exhibit particularly high therapeutic indices in treating disease
and disorders. The dosage of a compound of the inventions described
herein will preferably be within a range of circulating
concentrations that include an effective dose with little or no
toxicity.
3.8 Combination Therapy
[0418] In certain embodiments of the present invention, the
compounds of the invention can be used in combination therapy with
at least one other therapeutic agent. The compound of the invention
and the therapeutic agent can act additively or, more preferably,
synergistically. In a preferred embodiment, a composition
comprising a compound of the invention is administered concurrently
with the administration of another therapeutic agent, which can be
part of the same composition as the compound of the invention or a
different composition. In another embodiment, a composition
comprising a compound of the invention is administered prior or
subsequent to administration of another therapeutic agent.
4. EXAMPLES
[0419] The invention is further defined by reference to the
following examples, which describe in detail preparation of
compounds and compositions of the invention and assays for using
compounds and compositions of the invention. It will be apparent to
those skilled in the art that many modifications, both to materials
and methods, may be practiced without departing from the scope of
the invention.
[0420] In the examples below, the following abbreviations have the
following meanings. If an abbreviation is not defined, it has its
generally accepted meaning. [0421]
AIBN=2,2'-azobis(isobutyronitrile) [0422] Atm=atmosphere [0423]
Boc=tert-butyloxycarbonyl [0424] Cbz=carbobenzyloxy [0425]
CPM=counts per minute [0426] DCC=dicyclohexylcarbodiimide [0427]
DMAP=4-N,N-dimethylaminopyridine [0428] DMEM=Dulbecco's minimun
eagle medium [0429] DMF=N,N-dimethylformamide [0430]
DMSO=dimethylsulfoxide [0431] Fmoc=9-fluorenylmethyloxycarbonyl
[0432] g=gram [0433] h=hour [0434] HBSS=Hank's buffered saline
solution [0435] L=liter [0436] LC/MS=liquid chromatography/mass
spectroscopy [0437] M=molar [0438] min=minute [0439] mL=milliliter
[0440] mmol=millimoles [0441] NBS=N-bromosuccinimide [0442]
NHS=N-hydroxysuccinimide [0443] PBS=phosphate buffered saline
[0444] THF=tetrahydrofuran [0445] TFA=trifluoroacetic acid [0446]
TMS=trimethylsilyl [0447] .mu.L=microliter [0448] .mu.M=micromolar
[0449] v/v=volume to volume
Example 1
1-{[(.alpha.-Pivaloyloxymethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (51)
Step A: Chloromethyl n-Nitrophenyl Carbonate (52)
[0450] p-Nitrophenol (100 g, 0.72 moles) was dissolved in anhydrous
tetrahydrofuran (3 L) and stirred vigorously. To this solution was
added chloromethyl chloroformate (70 mL, 0.79 moles) at room
temperature followed by triethylamine (110 mL). After stirring for
1 hour, the reaction mixture was filtered and the filtrate was
concentrated and then diluted with ethyl acetate (1 L). The organic
solution was washed with 10% potassium carbonate (3.times.500 mL)
and 1N HCl (2.times.300 mL), brine (2.times.300 mL) and dried over
anhydrous sodium sulfate. Removal of the solvent gave 157 g (95%)
of the title compound (52) as a solid. The compound was unstable to
LC-MS. .sup.1H NMR (CDCl.sub.3, 400 MHz): 5.86 (s, 2H), 7.44 (d,
J=9 Hz, 2H), 8.33 (d, J=9 Hz, 2H).
Step B: Iodomethyl n-Nitrophenyl Carbonate (53)
[0451] Chloromethyl p-nitrophenyl carbonate (52) (100 g, 0.43
moles), sodium iodide (228 g, 1.30 moles) and 50 g of dried
molecular sieves (4 .ANG.) were added to 2 L of acetone under
nitrogen with mechanical stirring. The resulting mixture was
stirred at 40.degree. C. for 5 hours (monitored by .sup.1H NMR).
Upon completion, the solid materials were removed by filtration and
the solvent was removed under reduced pressure. The residue was
redissolved in dichloromethane (1 L) and washed twice with
saturated aqueous sodium carbonate (300 mL) followed by water (300
mL). The organic layer was separated and dried over anhydrous
sodium sulfate. Removal of solvent gave 123.6 g (89%) of the title
compound (53) as a solid upon standing. The compound was found to
be unstable to LC-MS. .sup.1H NMR (CDCl.sub.3, 400 MHz): 6.06 (s,
2H), 7.42 (d, J=9 Hz, 2H), 8.30 (d, J=9 Hz, 2H). .sup.13C NMR
(CDCl.sub.3, 100 MHz): 155.1, 151.0, 146.0, 125.8, 125.7, 121.9,
33.5.
Step C: Silver Pivalate (54)
[0452] Pivalic acid (50 g, 0.49 moles) was dissolved in
acetonitrile (1.3 L) followed by addition of silver oxide (70 g,
0.29 moles) with vigorous stirring. Then, 660 mL of water was added
under nitrogen. The resulting suspension was stirred at 70.degree.
C. in dark for 1 hour. After filtration through a pad of Celite,
removal of the solvent gave 86 g (82%) of the title compound (54)
as a pale white solid, which was used in the next reaction without
further purification.
[0453] Other silver salts described in this application are
prepared following similar procedures.
Step D: n-Nitrophenyl Pivaloyloxymethyl Carbonate (55)
[0454] To a solution of iodomethyl p-nitrophenyl carbonate (53) (62
g, 0.19 moles) in anhydrous toluene (1 L) was added silver pivalate
(80 g, 0.38 moles). After stirring at 55.degree. C. under nitrogen
for 3 h, the reaction mixture was allowed to cool to room
temperature and filtered through a pad of Celite. The filtrate was
washed with 10% potassium carbonate (500 mL). Removal of the
solvent yielded 43 g (75%) of the title compound (55) as a yellow
oil. .sup.1H NMR (CDCl.sub.3, 400 MHz): 1.25 (s, 9H), 5.88 (s, 2H),
7.40 (d, J=9 Hz, 2H), 8.29 (d, J=9 Hz, 2H). .sup.13C NMR
(CDCl.sub.3, 100 MHz): 177.0, 155.3, 151.6, 145.8, 125.6, 121.9,
83.1, 39.1, 27.0.
Step E:
1-{[(.alpha.-Pivaloyloxymethoxy)carbonyl]aminomethyl}-1-Cyclohexan-
e Acetic Acid (51)
[0455] Gabapentin free base (24 g, 0.14 moles) was slurried in
anhydrous dichloromethane (100 mL) and then treated with
chlorotrimethylsilane (18.6 mL, 0.28 moles) and triethylamine (10
mL, 0.15 moles), respectively. The resulting suspension was warmed
with stirring until complete dissolution of any solid was achieved.
The above gabapentin solution was added via an equalizing addition
funnel to a gently refluxed and mechanically stirred solution of
p-nitrophenyl pivaloyloxymethyl carbonate (55) (20 g, 67 mmol) and
triethylamine (10 mL, 0.15 moles) in dichloromethane (100 mL) under
nitrogen. The resulting yellow solution was stirred for 1.5 hours.
Upon completion (monitored by ninhydrin stain), the mixture was
filtered and the filtrate was concentrated. The residue was
dissolved in ethyl acetate (500 mL) and washed with 1N HCl
(3.times.100 mL), brine (2.times.100 mL) and dried over anhydrous
sodium sulfate. After removing the solvent, the crude product was
dissolved in ethanol (300 mL) and then 1 g of 5% Pd/C was added.
The resulting mixture was shaken under 50 psi hydrogen atmosphere
for 15 minutes and then filtered through a pad of Celite. After
concentration, the residue was dissolved in ethyl acetate, washed
with 5% H.sub.2SO.sub.4 and dried over anhydrous sodium sulfate.
After removing the solvent under reduced pressure, the residue was
purified by chromatography on silica gel (4:1 hexanes:ethyl
acetate) to afford 15 g (68%) of the title compound (51) as a
solid. M.p.: 79-81.degree. C.; .sup.1H NMR (CDCl.sub.3, 400 MHz):
1.21 (s, 9H), 1.3-1.5 (m, 10H), 2.32 (s, 2H), 3.26 (s, 2H), 5.33
(m, 1H), 5.73 (s, 2H). .sup.13C NMR (CDCl.sub.3, 400 MHz): 21.7,
26.2, 27.3, 34.3, 38.2, 39.2, 80.6, 155.9, 176.8, 178.0. MS (ESI)
m/z 328.36 (M-H).sup.-, 330.32 (M+H).sup.+, 352.33
(M+Na).sup.+.
Example 2
1-{[(.alpha.-Acetoxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (56)
Step A: 1-Chloroethyl-n-Nitrophenyl Carbonate (57)
[0456] To an ice cold reaction mixture containing p-nitrophenol
(1.39 g, 10 mmol) and pyridine (0.81 g, 10 mmol) in dichloromethane
(60 mL) was added 1-chloroethyl chloroformate (1.2 mL, 11 mmol).
The mixture was stirred at 0.degree. C. for 30 min and then at room
temperature for 1 hour. After removing the solvent under reduced
pressure, the residue was dissolved in ether, washed with water,
10% citric acid and water. The ether layer was dried over
Na.sub.2SO.sub.4 and evaporated under reduced pressure to give 2.4
g (97%) of the title compound (57) as an off-white solid. .sup.1H
NMR (CDCl.sub.3): 1.93 (d, 3H), 6.55 (q, 1H), 7.42 (d, 2H), 8.28
(d, 2H).
Step B: .alpha.-Acetoxyethyl-n-Nitrophenyl Carbonate (58)
[0457] A mixture of 1-chloroethyl-p-nitrophenyl carbonate (57) (0.5
g, 2 mmol) and mercuric acetate (1.5 g, 4.4 mmol) in acetic acid
(15 mL) was stirred at room temperature for 24 hours. After removal
of acetic acid under reduced pressure, the residue was dissolved in
ether and washed with water, 0.5% (v/v) aqueous NaHCO.sub.3, and
water. The ether layer was dried over Na.sub.2SO.sub.4, and
concentrated to dryness. Chromatography of the resulting residue on
silica gel, (hexanes:ethyl acetate (95:5)) gave 0.45 g (84%) of the
title compound (58). .sup.1H NMR (CDCl.sub.3, 400 MHz): 1.55 (d,
J=5.6 Hz, 3H), 2.07 (s, 3H), 6.78 (q, J=5.6 Hz, 1H), 7.36 (d, J=9.6
Hz, 2H), 8.22 (d, J=9.6 Hz, 2H).
Step C:
1-{[(.alpha.-Acetoxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (56)
[0458] To a mixture containing gabapentin (633 mg, 3.7 mmol) and
triethylamine (1.03 mL, 7.4 mmol) in dichloromethane (20 mL) was
added trimethylchlorosilane (0.93 mL, 7.4 mmol) and the mixture was
stirred until a clear solution was formed. A solution containing
.alpha.-acetoxyethyl-p-nitrophenyl carbonate (58) (1 g, 3.7 mmol)
in dichloromethane (10 mL) was then added and the resulting mixture
was stirred for 30 minutes. The reaction mixture was washed with
10% citric acid (20 mL) and the organic layer was separated. The
aqueous layer was further extracted with ether (3.times.10 mL) and
the combined organic extracts were dried over MgSO.sub.4. After
filtration, the organic solvent was removed under reduced pressure.
Chromatography of the resulting residue on silica gel,
(hexanes:ethyl acetate (4:1)), gave 700 mg (63%) of the title
compound (56). .sup.1H NMR (CDCl.sub.3, 400 MHz): 1.27-1.60 (m,
10H), 1.55 (d, 3H), 2.08 (s, 3H), 2.38 (s, 2H), 3.25 (m, 2H), 5.31
(t, 1H), 6.81 (q, 1H). MS (ESI) m/z 302.22 (M+H).sup.+. The acid
form was quantitatively converted to the corresponding sodium salt
by dissolution in water (5 mL), addition of an equimolar quantity
of 0.5 N NaHCO.sub.3, followed by lyophilization.
Example 3
1-{[(.alpha.-Benzoyloxybenzyloxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (59)
Step A: 6-Nitrophenyl .alpha.-Benzoylbenzylcarbonate (60)
[0459] To a solution of benzoin (2.0 g, 9.4 mmol) in 60 mL of
CH.sub.2Cl.sub.2 was added DMAP (1.21 g, 9.9 mmol) and
p-nitrophenyl-chloroformate (1.99 g, 9.9 mmol), respectively, at
room temperature. After stirring for 3 hours at room temperature,
the reaction was quenched with water and extracted with ethyl
acetate/hexane (2.times.100 mL). The combined organic extracts were
dried over anhydrous sodium sulfate. Removal of the solvent under
reduced pressure afforded the title compound (60), which was used
in the next reaction without purification.
Step B:
1-{[(.alpha.-Benzoylbenzyloxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (61)
[0460] To a suspension of gabapentin (1.70 g, 9.9 mmol) in
CH.sub.2Cl.sub.2 at 0.degree. C. was added triethylamine (2.76 mL,
19.8 mmol) and TMSCl (2.51 mL, 19.8 mmol). The reaction was then
stirred for 30 minutes at room temperature. To this mixture was
added compound (60) (prepared above in Step A) in CH.sub.2Cl.sub.2
and the resulting mixture was stirred at room temperature for 5
hours. The reaction mixture was diluted with dichloromethane,
washed with brine and the organic phase was dried over
Na.sub.2SO.sub.4. After removing the solvent under reduced
pressure, the residue was purified by chromatography on silica gel,
eluting with 5% methanol in CH.sub.2Cl.sub.2, to give 3.78 g (90%
over two steps) of the title compound (61). .sup.1H NMR
(CDCl.sub.3, 400 MHz): .delta. 1.48-1.35 (m, 10H), 2.30 (s, 2H),
3.24 (d, J=7.2 Hz, 2H), 5.58 (t, J=6.8 Hz, 1H), 6.85 (s, 1H),
7.50-7.33 (m, 8H), 7.93 (d, J=7.2 Hz, 2H).
Step C:
1-{[(.alpha.-Benzoyloxybenzyloxy)carbonyl]aminomethyl}-1-Cyclohexa-
ne Acetic Acid
[0461] To a solution of
1-{[(.alpha.-benzoylbenzyloxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid (61) (1.89 g, 4.6 mmol) in 40 mL of CH.sub.2Cl.sub.2
was added 77% mCPBA (2.07 g, 9.2 mmol) and NaHCO.sub.3 (0.78 g, 9.2
mmol), respectively, at room temperature and the resulting mixture
was stirred at room temperature overnight. The reaction mixture was
acidified with 10% citric acid and extracted with CH.sub.2Cl.sub.2.
The organic extract was washed with brine and dried over
Na.sub.2SO.sub.4. After removing the solvent under reduced
pressure, the residue was purified by reverse phase preparative
HPLC (acetonitrile-water, 0.1% formic acid) to afford 960 mg (49%)
of the title compound (59). .sup.1H NMR (CDCl.sub.3, 400 MHz):
.delta. 1.58-1.35 (m, 10H), 2.34 (s, 2H), 3.26 (dd, J=6.8, 0.8 Hz,
2H), 5.38 (t, J=6.8 Hz, 1H), 7.46-7.26 (m, 5H), 7.63-7.55 (m, 3H),
7.89 (s, 1H), 8.08 (dd, J=8.8, 1.2 Hz, 2H).
Example 4
1-{[(.alpha.-Acetoxybenzyloxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (62)
[0462] Following the procedure of Example 3, and substituting
1-hydroxy-1-phenyl-propan-2-one for benzoin, provided 300 mg of the
title compound (62). .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
1.41 (m, 10H), 2.19 (s, 3H), 2.33 (s, 2H), 3.27 (dd, J=6.6, 1.6 Hz,
2H), 5.36 (t, J=6.6 Hz, 1H), 7.40 (m, 3H), 7.52 (m, 2H), 7.63 (s,
1H).
Example 5
1-{[(.alpha.-Benzoyloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (64)
[0463] Following the procedure of Example 3, and substituting
2-hydroxy-1-phenyl-1-propanone for benzoin, provided 5 mg of the
title compound (63). .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
1.44-1.36 (m, 10H), 1.62 (d, J=5.6 Hz, 3H), 2.34 (s, 2H), 3.24 (d,
J=6.8 Hz, 2H), 5.28 (t, J=6.8 Hz, 1H), 7.06 (q. J=5.6 Hz, 1H), 7.44
(m, 2H), 7.56 (m, 1H), 8.03 (dd, J=8.4, 1.6 Hz, 2H).
Example 6
1-{[(1-Benzoyloxy-2-phenylethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (64)
Step A: 2-Phenyl-[1,3]-dithiane (65)
[0464] To a solution of benzaldehyde (10.6 g, 100 mmol) and
1,3-propane dithiol in CH.sub.2Cl.sub.2 (150 mL) at room
temperature was dropwise added BF.sub.3.Et.sub.2O (6.3 mL, 50 mmol)
and the resulting mixture was stirred at room temperature for 2
hours. The reaction mixture was then diluted with CH.sub.2Cl.sub.2,
filtered and the filtrate washed with brine, saturated NaHCO.sub.3,
brine and dried over Na.sub.2SO.sub.4. The solvent was removed
under reduced pressure to afford a white solid, which was
recrystallized from a 1:1 mixture of ether and hexane to afford
17.0 g (87%) of the title compound (65) as white crystalline
needles. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 1.91 (m, 1H),
2.14 (m, 1H), 2.89 (m, 2H), 3.04 (m, 2H), 5.16 (s, 1H), 7.35-7.28
(m, 3H), 7.46 (m, 2H).
Step B: 2-Phenyl-1-(2-phenyl-[1,3]-dithian-2-yl)-ethanol (66)
[0465] To a solution of 2-phenyl-[1,3]-dithiane (65) (4.0 g, 20.4
mmol) in THF at -30.degree. C. was added a 1.6 M solution of
n-butyllithium in THF (15.3 mL, 24.4 mmol). After stirring for 30
minutes at -30.degree. C., a solution of phenylacetylaldehyde (2.45
g, 20.4 mmol) in tetrahydrofuran was added dropwise at -30.degree.
C. The resulting reaction mixture was stirred for another hour at
0.degree. C. The reaction was quenched with saturated NH.sub.4Cl
solution and extracted with ethyl acetate. The combined organic
extracts were washed with saturated NH.sub.4Cl solution, brine and
dried over Na.sub.2SO.sub.4. After filtrating and concentrating,
the crude product was purified by flash chromatography on silica
gel, (25% ethyl acetate in hexanes), to afford 2.63 g (71%) of the
title compound (66). .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
1.97 (m, 2H), 2.23 (dd, J=4.0, 1.2 Hz, 1H), 2.43 (dd, J=13.6, 10.2
Hz, 1H), 2.77 (m, 4H), 3.02 (d, J=13.6 Hz, 1H), 4.07 (m, 1H),
7.44-7.13 (m, 8H), 8.02 (dd, J=8.4, 1.4 Hz, 2H).
Step C: 2-Hydroxy-1,3-diphenyl-propan-1-one (67)
[0466] To a solution of
2-phenyl-1-(2-phenyl-[1,3]-dithian-2-yl)-ethanol (66) (2.50 g, 7.9
mmol) in 100 mL of a 9:1 mixture of acetonitrile and water was
added mercuric perchlorate hydrate (4.1 g, 10.3 mmol). The
resulting mixture was stirred at room temperature for 5 minutes and
thin layer chromatography indicated that the reaction was
completed. The mixture was diluted with ethyl acetate, filtered
through a pad of Celite and the filtrate was washed with saturated
NaHCO.sub.3, brine and dried over Na.sub.2SO.sub.4. The solvent was
removed under reduced pressure and the crude product was purified
by flash chromatography on silica gel, (20% ethyl acetate in
hexanes) to afford 1.32 g (74%) of the title compound (67). .sup.1H
NMR (CDCl.sub.3, 400 MHz): .delta. 2.90 (dd, J=14.4, 7.0 Hz, 1H),
3.20 (dd, J=14.4, 4.0 Hz, 1H), 3.70 (d, J=6.8 Hz, 1H), 5.35 (m,
1H), 7.28-7.11 (m, 5H), 7.53 (m, 2H), 7.65 (m, 1H), 7.93 (d, J=7.2
Hz, 2H).
Step D:
1-{[(1-Benzoyloxy-2-phenylethoxy)carbonyl]aminomethyl}-1-Cyclohexa-
ne Acetic Acid (64)
[0467] Following the procedure of Example 3, and substituting
2-hydroxy-1,3-diphenyl-propan-1-one for benzoin, provided 181 mg of
the title compound (64). .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
1.45-1.29 (m, 10H), 2.24 (d, J=13.6 Hz, 1H), 2.28 (d, J=13.6 Hz,
1H), 3.22 (m, 4H), 5.26 (t, J=6.6 Hz, 1H), 7.16 (t, J=5.6 Hz, 1H),
7.33-7.25 (m, 5H), 7.40 (m, 2H), 7.57 (m, 1H), 8.02 (m, 2H).
Example 7
1-{[(1-(3-Methylbutanoyloxy)-2-phenylethoxy)carbonyl]aminomethyl}-1-Cycloh-
exane Acetic Acid (68)
[0468] Following the procedure of Example 6 and substituting
3-methylbutyraldehyde for benzaldehyde in Step A, provided 95 mg of
the title compound (68). .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
0.88-0.90 (m, 6H), 1.16-1.29 (m, 10H), 2.06 (m, 1H), 2.16 (m, 2H),
2.26 (m, 2H), 3.08 (d, J=6.8 Hz, 2H), 3.19 (m, 2H), 5.22 (t, J=6.8
Hz, 1H), 6.93 (t, J=6 Hz, 1H), 7.31-7.23 (m, 5H).
Example 8
1-{[(.alpha.-Benzoyloxybutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (69)
[0469] Following the procedure of Example 6 and substituting
butyraldehyde for phenylacetaldehyde in Step B, provided 240 mg of
the title compound (69). .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
0.99 (t, J=7.6 Hz, 3H), 1.52-1.38 (m, 12H), 1.89 (m, 2H), 2.31 (s,
2H), 3.24 (m, 2H), 5.34 (t, J=6.6 Hz, 1H), 6.70 (t, J=5.6 Hz, 1H),
7.42 (m, 2H), 7.56 (m, 1H), 8.04 (m, 2H).
Example 9
1-{[(.alpha.-Acetoxybutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (70)
[0470] Following the procedure of Example 6, and substituting
acetaldehyde for benzaldehyde in Step A and substituting
butyraldehyde for phenylacetaldehyde in Step B respectively,
provided 42 mg of the title compound (70). .sup.1H NMR (CD.sub.3OD,
400 MHz): .delta. 0.95 (m, 3H), 1.52-1.31 (m, 12H), 1.72 (m, 2H),
2.02 (s, 3H), 2.27 (s, 2H), 3.20 (s, 2H), 6.67 (t, J=5.6 Hz,
1H).
Example 10
1-{[(.alpha.-Butanoyloxybutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (71)
[0471] Following the procedure of Example 3, and substituting
butyroin for benzoin, provided 210 mg of the title compound (71).
.sup.1H NMR (CDCl.sub.3, 400 MHz); .delta. 0.93 (m, 6H), 1.37-1.76
(m, 16H), 2.30 (m, 4H), 3.23 (m, 2H), 5.25 (broad triplet, 1H),
6.73 (m, 1H). MS (ESI) m/z 356.45 (M-H).sup.+.
Example 11
1-{[(.alpha.-Propanoyloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (72)
Step A: 1-Iodoethyl-p-Nitrophenyl Carbonate (73)
[0472] A mixture of 1-chloroethyl-p-nitrophenyl carbonate (0.5 g, 2
mmol) and NaI (0.6 g, 4 mmol) in dry acetone was stirred for 3
hours at 40.degree. C. After filtration, the filtrate was
concentrated under reduced pressure to afford 480 mg (72%) of the
title compound (73), which was used in the next reaction without
further purification.
Step B: .alpha.-Propanoyloxyethyl-n-Nitrophenyl Carbonate (74)
[0473] A mixture of 1-iodoethyl-p-nitrophenyl carbonate (73) (0.51
g, 1.5 mmol) and silver propionate (0.54 g, 3 mmol) in toluene (20
mL) was stirred at 50.degree. C. for 24 hours. The reaction mixture
was filtered to remove solids and the filtrate concentrated under
reduced pressure. Chromatography of the resulting residue on silica
gel, (20% CH.sub.2Cl.sub.2/hexanes and then 40%
CH.sub.2Cl.sub.2/hexanes), gave 0.39 g (92%) of the title compound
(74). .sup.1H NMR (CDCl.sub.3, 400 MHz): 1.16 (t, J=7.6 Hz, 3H),
1.61 (d, J=5.6 Hz, 3H), 2.41 (q, J=7.6 Hz, 2H), 6.84 (q, 1H, J=5.6
Hz), 7.39 (d, J=9.2 Hz, 2H), 8.28 (d, J=9.2 Hz, 2H).
Step C:
1-{[(.alpha.-Propanoyloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexan-
e Acetic Acid
[0474] To a mixture of gabapentin (160 mg, 2.76 mmol) and
triethylamine (0.77 mL, 5.5 mmol) in dichloromethane (30 mL) was
added trimethylchlorosilane (0.71 mL, 5.5 mmol) and the resulting
mixture was stirred until a clear solution was formed. To the above
solution was added a solution of
.alpha.-propanoyloxyethyl-p-nitrophenyl carbonate (74) (0.39 g, 1.4
mmol) in dichloromethane (10 mL). After stirring for 30 minutes the
reaction mixture was washed with 10% citric acid (20 mL) and the
organic layer was separated. The aqueous layer was further
extracted with ether (3.times.10 mL) and the combined organic
extracts were dried over MgSO.sub.4. After removing the solvent
under reduced pressure, the residue was purified by reverse phase
preparative HPLC (acetonitrile, water, 1% formic acid) to afford
190 mg (44%) of the title compound (72). .sup.1H NMR (CD.sub.3OD,
400 MHz): 1.09 (t, J=7.6 Hz, 3H), 1.36-1.54 (m, 10H), 1.44 (d,
J=5.6 Hz, 3H), 2.28 (s, 2H), 2.31 (q, J=7.6 Hz, 2H), 3.22 (s, 2H),
6.67 (q, J=5.6 Hz, 1H). MS (ESI) m/z 316.25 (M+H).sup.+.
Example 12
1-{[(.alpha.-Butanoyloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (75)
Step A: .alpha.-Butanoyloxyethyl-p-Nitrophenyl Carbonate (76)
[0475] A mixture of 1-iodoethyl-p-nitrophenyl carbonate (73) (1.5
g, 4.5 mmol) and silver butyrate (1.3 g, 6.7 mmol) in toluene (40
mL) was stirred at 90.degree. C. in an oil bath for 24 h. The
reaction mixture was filtered and the filtrate was concentrated
under reduced pressure. Chromatography of the resulting residue on
silica gel, (20% CH.sub.2Cl.sub.2/hexanes and then 40%
CH.sub.2Cl.sub.2/hexanes), gave 0.46 g (36%) of the title compound
(76). .sup.1H NMR (CDCl.sub.3, 400 MHz): 0.95 (t, J=7.6 Hz, 3H),
1.61 (d, J=5.6 Hz, 3H), 1.67 (m, 2H), 2.41 (t, J=7.6 Hz, 2H), 6.84
(q, 1H, J=5.6 Hz), 7.39 (d, J=9.2 Hz, 2H), 8.28 (d, J=9.2 Hz, 2H).
MS (ESI) m/z 298.28 (M+H).sup.+.
Step B:
1-{[(.alpha.-Butanoyloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (75)
[0476] To a mixture containing gabapentin (530 mg, 3.1 mmol) and
triethylamine (0.89 mL, 6.4 mmol) in dichloromethane (30 mL) was
added trimethylchlorosilane (0.83 mL, 6.4 mmol) and the resulting
mixture was stirred until a clear solution was formed. To this
solution was added a solution of
.alpha.-butanoyloxyethyl-p-nitrophenyl carbonate (76) (0.46 g, 1.6
mmol) in dichloromethane (10 mL) and the resulting mixture was
stirred for 30 min. The reaction mixture was washed with 10% citric
acid (20 mL) and the organic phase was separated. The aqueous layer
was further extracted with ether (3.times.10 mL) and the combined
organic phases were dried over MgSO.sub.4, then concentrated in
vacuo. The resulting residue was purified by reverse phase
preparative HPLC (acetonitrile, water 0.1% formic acid) to afford
70 mg (21%) of the title compound (75). .sup.1H NMR (CD3OD, 400
MHz): 0.95 (t, J=7.6 Hz, 3H), 1.32-1.58 (m, 10H), 1.42 (d, J=5.6
Hz, 3H), 1.67 (m, 2H), 2.24 (s, 2H), 2.30 (t, J=7.6 Hz, 2H), 3.24
(s, 2H), 6.74 (q, J=5.6 Hz, 1H). MS (ESI) m/z 330.28
(M+H).sup.+.
[0477] The acid form was quantitatively converted to the
corresponding sodium salt by dissolution in water (5 mL), addition
of an equimolar quantity of 0.5 N NaHCO.sub.3, followed by
lyophilization.
Example 13
1-{[(.alpha.-Isobutanoyloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (77)
[0478] Following the procedure of Example 12, and substituting
silver isobutyrate for silver butyrate, provided 70 mg (21%) of the
title compound (77). .sup.1H NMR (CD.sub.3OD, 400 MHz): 1.12 (d,
J=7.2 Hz, 3H), 1.14 (d, J=7.2 Hz, 3H), 1.32-1.58 (m, 10H), 1.44 (d,
J=5.6 Hz, 3H), 2.28 (s, 2H), 2.56 (m, 1H), 3.25 (m, 2H), 6.73 (q,
J=5.6 Hz, 1H). MS (ESI) m/z 330.30 (M+H).sup.+.
[0479] The acid form was quantitatively converted to the
corresponding sodium salt by dissolution in water (5 mL), addition
of an equimolar quantity of 0.5 N NaHCO.sub.3, followed by
lyophilization.
Example 14
1-{[(.alpha.-Pivaloxyethoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (78)
[0480] Following the procedure of Example 12, and substituting
silver pivalate for silver butyrate, provided 80 mg (36%) of the
title compound (78). .sup.1H NMR (CDCl.sub.3, 400 MHz): 1.13 (s,
9H), 1.32-1.58 (m, 10H), 1.41 (d, J=5.6 Hz, 3H), 2.27 (s, 2H), 3.25
(m, 2H), 5.41 (t, 1H), 6.73 (q, J=5.6 Hz, 1H). MS (ESI) m/z 344.20
(M+H).sup.+.
[0481] The acid form was quantitatively converted to the
corresponding sodium salt by dissolution in water (5 mL), addition
of an equimolar quantity of 0.5 N NaHCO.sub.3, followed by
lyophilization.
Example 15
1-{[(.alpha.-Acetoxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (79)
[0482] Following the procedure of Example 2, and substituting
1-chloro-2-methylpropyl chloroformate for 1-chloroethyl
chloroformate, provided 212 mg (38%) of the title compound (79).
.sup.1H NMR (CD.sub.3OD, 400 MHz): 0.99 (m, 6H), 1.32-1.58 (m,
10H), 1.88 (m, 1H), 2.08 (s, 3H), 2.38 (s, 2H), 3.25 (s, 2H), 6.52
(d, J=4.4 Hz, 1H); MS (ESI) m/z 330.30 (M+H).sup.+.
Example 16
1-{[(.alpha.-Propanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (80)
[0483] Following the procedure of Example 11, and substituting
1-chloro-2-methylpropyl-p-nitrophenyl carbonate for
1-chloroethyl-p-nitrophenyl carbonate, provided 190 mg (44%) of the
title compounds (80). .sup.1H NMR (CD.sub.3OD, 400 MHz): 0.90 (d,
J=6.6 Hz, 3H), 0.91 (d, J=6.6 Hz, 3H), 0.98 (t, J=7.6 Hz, 3H),
1.32-1.58 (m, 10H), 1.83 (m, 1H), 2.18 (s, 2H), 2.28 (q, J=7.6 Hz,
2H), 3.25 (s, 2H), 6.52 (d, J=4.4 Hz, 1H). MS (ESI) m/z 344.34
(M+H).sup.+.
Example 17
1-{[(.alpha.-Butanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (81)
[0484] Following the procedure of Example 2 and substituting
1-chloro-2-methylpropyl chloroformate and mercuric butyrate for
1-chloroethyl chloroformate and mercuric acetate, respectively,
provided 95 mg (36%) of the title compound (81). .sup.1H NMR
(CD.sub.3OD, 400 MHz): 1.12 (t, J=7.6 Hz, 3H), 1.13 (d, J=6.6 Hz,
3H), 1.14 (d, J=6.6 Hz, 3H), 1.32-1.58 (m, 10H), 1.87 (m, 2H), 2.22
(m, 1H), 2.42 (s, 2H), 2.46 (t, J=7.6 Hz, 2H), 3.44 (m, 2H), 6.78
(d, J=4.8 Hz, 1H). MS (ESI) m/z 358.30 (M+H).sup.+.
Example 18
1-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (82)
[0485] Following the procedure of Example 2, and substituting
1-chloro-2-methylpropyl chloroformate and mercuric isobutyrate for
1-chloroethyl chloroformate and mercuric acetate, respectively,
provided 95 mg (36%) of the title compound (82). .sup.1H NMR
(CD.sub.3OD, 400 MHz): 0.95 (d, J=7.2 Hz, 3H), 0.97 (d, J=7.2 Hz,
3H), 1.05 (d, J=6.6 Hz, 3H), 1.06 (d, J=6.6 Hz, 3H), 1.32-1.58 (m,
10H), 1.98 (m, 1H), 2.24 (s, 2H), 2.45 (m, 1H), 3.24 (m, 2H), 6.42
(d, J=4.8 Hz, 1H). MS (ESI) m/z 358.27 (M+H).sup.+.
Example 19
1-{[(.alpha.-Pivaloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (83)
[0486] Following the procedure of Example 12, and substituting
1-chloro-2-methylpropyl-p-nitrophenyl carbonate and silver pivalate
for 1-chloroethyl-p-nitrophenyl carbonate and silver butyrate,
respectively, provided 10 mg (9%) of the title compound (83).
.sup.1H NMR (CD.sub.3OD, 400 MHz): 0.98 (d, J=6.6 Hz, 3H), 0.99 (d,
J=6.6 Hz, 3H), 1.19 (s, 9H), 1.32-1.58 (m, 10H), 2.08 (m, 1H), 2.28
(s, 2H), 3.21 (m, 2H), 6.49 (d, 1H); MS (ESI) m/z 372.31
(M+H).sup.+.
Example 20
1-{[(.alpha.-Benzoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (84)
[0487] Following the procedure of Example 11, and substituting
1-chloro-2-methylpropyl-p-nitrophenyl carbonate and silver benzoate
for 1-chloroethyl 1-p-nitrophenyl carbonate and silver propionate,
respectively, provided 109 mg (40%) of the title compound (84).
.sup.1H NMR (CD.sub.3OD, 400 MHz): 1.18 (d, J=7.2 Hz, 6H),
1.32-1.58 (m, 10H), 2.42 (m, 1H), 2.28 (s, 2H), 3.45 (s, 2H), 6.99
(d, J=4.8 Hz, 1H), 7.76 (m, 2H), 7.92 (m, 1H), 8.26 (m, 2H). MS
(ESI) m/z 392.22 (M+H)+.
Example 21
1-{[(.alpha.-Acetoxyisopropoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (85)
Step A: Isopropenyl-p-Nitrophenyl Carbonate (86)
[0488] To a mixture of p-nitrophenol (5.76 g, 41.5 mmol) and
isopropenyl chloroformate (5 g, 41.5 mmol) in dichloromethane (200
mL) at 0.degree. C. was added a solution of pyridine (3.4 mL, 42
mmol) in dichloromethane (50 mL). The resulting mixture was stirred
at 0.degree. C. for 30 minutes and then at room temperature for 1
hour. After removing the solvent under reduced pressure, the
residue was dissolved in ether and washed with water, 10% citric
acid and water again. The ether layer was dried over
Na.sub.2SO.sub.4 and evaporated under reduced pressure to give 8.7
g (94%) of the title compound (86) as an off-white solid. .sup.1H
NMR (CDCl.sub.3, 400 MHz): 2.05 (s, 3H), 4.81 (m, 1H), 4.95 (d, J=2
Hz, 1H), 7.42 (d, J=9.2 Hz, 2H), 8.28 (d, J=9.2 Hz, 2H).
Step B: 2-Chloroisopropyl-Nitrophenyl Carbonate (87)
[0489] Isopropenyl-p-nitrophenyl carbonate (86) (8.7 g, 39 mmol)
was dissolved in 4 M hydrogen chloride/dioxane in a sealed vessel.
The mixture was stirred at room temperature for 16 hours. Removal
of the solvent under reduced pressure gave 10 g (100%) of the title
compound (87), which was used in the next reaction without further
purification. .sup.1H NMR (CDCl.sub.3, 400 MHz): 2.10 (s, 6H), 7.42
(d, 2H, J=9.2 Hz), 8.28 (d, J=9.2 Hz, 2H).
Step C: .alpha.-Acetoxyisopropyl-1-Nitrophenyl Carbonate (88)
[0490] A mixture of 2-chloroisopropyl-p-nitrophenyl carbonate (87)
(0.5 g, 1.93 mmol) and mercuric acetate (1.0 g, 3.13 mmol) in
dichloromethane (20 mL) was stirred at room temperature for 24
hours. The reaction mixture was filtered to remove solid and the
filtrate concentrated under reduced pressure. Chromatography of the
resulting residue on silica gel, (20% CH.sub.2Cl.sub.2/hexanes and
then 40% CH.sub.2Cl.sub.2/hexanes), afforded 227 mg (50%) of the
title compound (88). .sup.1H NMR (CDCl.sub.3, 400 MHz): 1.90 (s,
6H), 2.07 (s, 3H), 7.28 (d, 2H, J=9.2 Hz), 8.28 (d, J=9.2 Hz,
2H).
Step D:
1-{[(.alpha.-Acetoxyisopropoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (85)
[0491] To a mixture containing gabapentin (257 mg, 1.5 mmol) and
triethylamine (0.46 mL, 3.3 mmol) in dichloromethane (30 mL) was
added trimethylchlorosilane (0.38 mL, 3 mmol) and the mixture
stirred until clear. A solution containing
ao-acetoxyisopropyl-p-nitrophenyl carbonate (88) (0.23 g, 0.8 mmol)
in dichloromethane (10 mL) was added and stirred for 30 minutes.
The reaction mixture was washed with brine (10 mL) and the organic
layer was separated. The aqueous layer was further extracted with
ether (3.times.10 mL) and the combined organic extracts were dried
over MgSO.sub.4 and then concentrated in vacuo. Chromatography of
the resulting residue on silica gel, (hexane:ethyl acetate (4:1)),
gave 40 mg (16%) of the title compound (85). .sup.1H NMR
(CD.sub.3OD, 400 MHz): 1.32-1.58 (m, 10H), 1.80 (s, 6H), 2.02 (s,
3H), 2.27 (s, 2H), 3.30 (s, 2H). MS (ESI) m/z 316.21
(M+H).sup.+.
Example 22
1-{[(.alpha.-Butanoyloxyisopropoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (89)
[0492] Following the procedure of Example 21, and substituting
mercuric butyrate for mercuric acetate, provided 5 mg (5%) of the
title compound (89). .sup.1H NMR (CD.sub.3OD, 400 MHz): 0.99 (t,
J=7.6 Hz, 3H), 1.32-1.58 (m, 10H), 1.60 (m, 2H), 1.85 (s, 6H), 2.22
(t, J=7.6, 2H), 2.27 (s, 2H), 3.20 (s, 2H). MS (ESI) m/z 344.24
(M+H)+, 366.30 (M+Na)+.
Example 23
1-{[(.alpha.-Isobutanoyloxyisopropoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (90)
[0493] Following the procedure of Example 21, and substituting
mercuric isobutyrate for mercuric acetate, provided 109 mg (43%) of
the title compound (90). .sup.1H NMR (CD.sub.3OD, 400 MHz): 1.19
(d. J=7.2 Hz, 6H), 1.32-1.58 (m, 10H), 1.82 (s, 6H), 2.38 (s, 2H),
3.25 (s, 2H). MS (ESI) 344.22 (M+H).sup.+, 366.24 (M+Na).sup.+.
Example 24
1-{[(.alpha.-Benzoyloxyisopropoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (91)
[0494] Following the procedure of Example 21, and substituting
mercuric benzoate for mercuric acetate, provided 170 mg (58%) of
the title compound (91). .sup.1H NMR (CDCl.sub.3, 400 MHz):
1.32-1.58 (m, 10H), 1.95 (s, 6H), 2.30 (s, 2H), 3.20 (d, J=6.8,
2H), 5.41 (t, J=6.8 Hz, 1H), 7.40 (m, 2H), 7.52 (m, 1H), 7.98 (m,
2H). MS (ESI) m/z 400.29 (M+Na).sup.+.
Example 25
1-{[(.alpha.-Nicotinoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (92)
Step A:
1-{[(.alpha.-Chloroisobutoxy)carbonyl]aminomethyl-1-Cyclohexane
Acetic Acid (93)
[0495] To a mixture containing gabapentin (1.71 g, 10 mmol) and
triethylamine (3.06 mL, 22 mmol) in dichloromethane (150 mL) was
added trimethylchlorosilane (1.4 mL, 11 mmol) and the resulting
mixture was stirred until clear (about 20 min). A solution
containing 1-chloro-2-methylpropylchloroformate (1.27 mL, 11 mmol)
in dichloromethane (10 mL) was then added at 0.degree. C. and
stirred at room temperature for 60 min. The reaction mixture was
washed with 10% citric acid (30 mL) and the organic layer
separated. The aqueous layer was further extracted with ether
(3.times.20 mL) and the combined organic phases were dried over
MgSO.sub.4 and then concentrated in vacuo. Chromatography of the
residue on silica gel, eluting with hexane:ethyl acetate (1:4) gave
2.37 g (77%) of the title compound. .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 1.04 (d, J=6.4 Hz, 3H), 1.06 (d, J=6.4 Hz, 3H),
1.36-1.53 (m, 10H), 2.15 (m, 1H), 2.34 (s, 2H), 3.24 (m, 2H), 5.39
(t, 1H), 6.32 (d, J=5.6 Hz), 1H). MS (ESI) m/z 306.34
(M+H.sup.+).
Step B:
1-{[(.alpha.-Nicotinoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cycloh-
exane Acetic Acid
[0496] A mixture of (93) (268 mg, 0.88 mmol),
1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (158 .mu.L, 1.01 mmol),
and nicotinic acid (637 mg, 5.2 mmol) in acetone was stirred at
room temperature for 48 h. After filtration, the filtrate was
concentrated in vacuo and the resulting residue was purified by
reverse phase preparative HPLC to afford 50 mg (14%) of the title
compound. .sup.1H NMR (CD.sub.3OD, 400 MHz): .delta. 1.07 (d, J=6.8
Hz, 3H), 1.09 (d, J=6.8 Hz, 3H), 1.32-1.58 (m, 10H), 2.19 (m, 1H),
2.26 (s, 2H), 3.23 (m, 2H), 6.78 (d, J=4.8 Hz, 1H), 7.58 (m, 1H),
8.39 (d, J=6.4 Hz, 1H), 8.76 (d, J=4.4 Hz, 1H), 9.10 (s, 1H). MS
(ESI) m/z 393.42 (M+H.sup.+).
Example 26
1-{[(.alpha.-2,2-Diethoxyproanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cycl-
ohexane Acetic Acid (94)
Step A: Benzyl
1-{[(.alpha.-Chloroisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetate (95)
[0497] To a solution of (93) (1.02 g, 3.34 mmol) in dichloromethane
was added 1,3-dicyclohexylcarbodiimide (758 mg, 3.67 mmol). After
stirring at room temperature for 30 min, benzyl alcohol (380 .mu.L,
3.67 mmol) and 4-(dimethylamino)pyridine (catalytic amount) were
added. The resulting mixture was stirred at room temperature of 16
h. After filtration, the filtrate was washed with 10% citric acid,
dried over Na.sub.2SO.sub.4, and concentrated. Chromatography of
the residue on silica gel, eluting with 10% ethyl acetate/hexane,
gave 820 mg (62%) of the title compound. .sup.1H NMR (CDCl.sub.3,
400 MHz): .delta. 1.03 (d, J=6.4 Hz, 3H), 1.05 (d, J=6.4 Hz, 3H),
1.36-1.53 (m, 10H), 2.13 (m, 1H), 2.35 (s, 2H), 3.22 (m, 2H), 5.11
(s, 2H), 5.49 (t, 1H), 6.32 (d, J=4.8 Hz), 1H), 7.34 (m, 5H). MS
(ESI) m/z 396.24 (M+H+).
Step B: Cesium 2,2-Diethoxypropionate (96)
[0498] To a stirred solution of 14 mL (0.2 mol) of pyruvic acid and
80 mL of triethylorthoformate at 10.degree. C. was added 1 mL of
concentrated sulfuric acid. The resulting mixture was stirred at
5-10.degree. C. for 1 h and then diluted with 200 mL of
dichloromethane. The organic solution was washed successively with
water (3.times.80 mL) and saturated sodium chloride solution (80
mL) and then dried over anhydrous sodium sulfate. The mixture was
filtered and then concentrated to give a quantitative yield of
2,2-diethoxypropionic acid as an oil. .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 1.30 (t, 6H), 1.61 (s, 3H), 3.57 (q, 4H), 8.62 (s,
1H). The acid form was quantitatively converted to its cesium salt
by dissolving the acid in water (25 mL) followed by treatment with
an equimolar quantity of cesium carbonate, and then lyophilization.
.sup.1H NMR (D.sub.2O, 400 MHz): .delta. 0.98 (t, 6H), 1.28 (s,
3H), 3.22 (q, 2H), 3.47 (q, 2H).
Step C: Benzyl
1-{[(.alpha.-2,2-Diethoxypropanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cy-
clohexane Acetate (97
[0499] A mixture of (95) (200 mg, 0.51 mmol) and sodium iodide (114
mg, 0.76 mmol) in acetone was stirred at room temperature for 1 h.
Cesium 2,2-diethoxypropionate (96) (300 mg, 1.02 mmol) and DMF (20
mL) were added and the resulting mixture was stirred at 40.degree.
C. for 18 h. After filtration, the filtrate was concentrated and
the resulting residue was purified by silica gel flash column
chromatography, eluting with 10% ethyl acetate/hexane to afford 100
mg (37%) of the title compound. MS (ESI) m/z 522.34
(M+H.sup.+).
Step D:
1-{[(.alpha.-2,2-Diethoxypropanoyloxyisobutoxy)carbonyl]aminomethy-
l}-1-Cyclohexane Acetic Acid (94)
[0500] A mixture of (97) (200 mg, 0.38 mmol) and 5%
Pd--C(catalytically amount) was stirred under hydrogen at room
temperature for 16 h. After filtration, the filtrate was
concentrated and the resulting residue was purified by reverse
phase preparative HPLC to afford 98 mg (60%) of the title compound.
.sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 0.97 (d, J=6.8 Hz, 6H),
1.19 (t, J=6.4 Hz, 3H), 1.21 (t, J=6.4 Hz, 3H), 1.32-1.58 (m, 10H),
1.51 (s, 3H), 2.06 (m, 1H), 2.30 (s, 2H), 3.23 (m, 2H), 3.46 (m,
2H), 3.56 (m, 2H), 5.30 (t, 1H, NH), 6.59 (d, J=4.8 Hz, 1H). MS
(ESI) m/z 432.24 (M+H.sup.+).
Example 27
1-{[(.alpha.-(2-Amino-2-methylpropanoyl)oxyisobutoxy)carbonyl]aminomethyl}-
-1-Cyclohexane Acetic Acid (98)
[0501] Following the procedure of Example 26, and substituting
2-amino-2-methylpropionic acid for 2,2-diethoxypropionic acid,
provided the title compound. .sup.1H NMR (CDCl.sub.3, 400 MHz):
.delta. 0.97 (d, J=6.8 Hz, 6H), 1.44 (s, 3H), 1.45 (s 3H),
1.32-1.58 (m, 10H), 2.05 (m, 1H), 2.30 (s, 2H), 3.23 (m, 2H), 5.50
(t, 1H, NH), 6.58 (d, J=4.8 Hz, 1H). MS (ESI) m/z 373.48
(M+H.sup.+).
Example 28
1-{[(.alpha.-Isobutanoyloxybutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (99)
Step A: 2-Isopropyl-1,3-Dithiane (100)
[0502] To a mixture of isobutyraldehyde (9.1 mL, 100 mmol) and
1,3-propanedithiol (10 mL, 100 mmol) in dichloromethane at
0.degree. C. was added boron trifluoride diethyl etherate (6.4 mL,
50 mmol). The resulting mixture was stirred at 0.degree. C. for 30
min and at room temperature for 30 min. The reaction mixture was
washed with brine, 5% NaHCO.sub.3, and brine again. The organic
phase was separated and dried over Na.sub.2SO.sub.4, then
concentrated to give 16 g (100%) of the title compound as a yellow
liquid. This was carried to the next step without further
purification. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 1.057 (d,
J=7.2 Hz, 3H), 1.059 (d, J=7.2 Hz, 3H), 1.80 (m, 1H), 1.97-2.08 (m,
2H), 2.82 (m, 4H), 4.00 (d, J=5.2 Hz, 1H).
Step B: 2-Isopropyl-2-(.alpha.-Hydroxybutyl-1,3-Dithiane (101)
[0503] To a solution of (100) (4 g, 24.7 mmol) in anhydrous
tetrahydrofuran (50 mL) at -20.degree. C. was dropwise added
n-butyl lithium (1.6M in hexane, 18.5 mL, 29.6 mmol). The stirred
mixture was allowed to warm room temperature over 4 h and then
cooled to -20.degree. C. again. To this solution was added slowly a
solution of n-butyraldehyde (2.7 mL, 29.6 mmol) in anhydrous
tetrahydrofuran (10 mL). The resulting mixture was stirred for 16 h
between -20.degree. C. and room temperature. The reaction was
quenched with saturated ammonium chloride solution and the mixture
extracted with ethyl acetate. The organic layer was separated and
dried over Na.sub.2SO.sub.4. After removing the solvent under
reduced pressure, flash column chromatography of the residue on
silica gel, eluting with 5% ethyl acetate/hexane provided 5 g (85%)
of the title compound as a yellow oil. .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 0.96 (t, J=7.2 Hz, 3H), 1.11 (d, J=6.8, Hz, 3H), 1.17
(d, J=6.8 Hz, 3H), 1.42-1.52 (m, 2H), 1.76 (m, 1H), 1.87-1.95 (m,
2H), 2.04 (m, 2H), 2.62 (m, 4H), 2.94 (m, 2H), 4.03 (d, J=5.2 Hz,
1H).
Step C: 4-Hydroxy-2-Methylheptan-3-one (102)
[0504] To a solution of (101) (5.0 g, 21.4 mmol) in acetonitrile
(270 mL) was added under vigorous stirring a solution of
Hg(ClO.sub.4).sub.2 in methanol (30 mL). The resulting mixture was
stirred at room temperature for 2 h. After filtration, the filtrate
was carefully concentrated under reduced pressure without heating.
Purification of the residue using silica gel flash column
chromatography (10% ethyl acetate/hexane) provided 2.8 g (91%) of
the title compound as colorless liquid. .sup.1H NMR (CDCl.sub.3,
400 MHz): .delta. 0.91 (t, J=7.2 Hz, 3H), 1.09 (d, J=7.2 Hz, 3H),
1.10 (d, J=7.2 Hz, 3H), 1.35-1.46 (m, 4H), 1.75 (m, 1H), 2.80 (m,
1H), 3.45 (d, J=5.2 Hz, 1H), 4.29 (m, 1H).
Step D: 2-Methylheptan-3-one-4-p-Nitrophenyl Carbonate (103)
[0505] To a mixture of (102) (1.1 g, 7.6 mmol), p-nitrophenyl
chloroformate (1.84 g, 9.2 mmol) in anhydrous dichloromethane at
0.degree. C. was added slowly a solution of 4-dimethylaminopyridine
(1.12 g, 9.2 mmol) in dichloromethane. After stirring for 1 h at
0.degree. C. and for 4 h at room temperature, the reaction was
quenched with 10% citric acid. The organic phase was separated,
dried over Na.sub.2SO.sub.4, and concentrated in vacuo. Flash
column chromatography of the residue, eluting with 30%
dichloromethane/hexane, provided 2 g (85%) of the title compound as
an off-white solid. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 0.99
(t, J=7.6 Hz, 3H), 1.12 (d, J=6.8 Hz, 3H), 1.18 (d, J=6.8 Hz, 3H),
1.51 (m, 2H), 1.84 (m, 2H), 2.82 (m, 1H), 5.17 (m, 1H), 7.42 (d,
J=6.8 Hz, 2H), 8.25 (d, J=6.8 Hz, 2H).
Step E:
1-{[(.alpha.-Isobutanoylbutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetic Acid (104)
[0506] To a mixture containing gabapentin (820 mg, 4.8 mmol) and
triethylamine (1.35 mL, 9.6 mmol) in dichloromethane (20 mL) was
added trimethylchlorosilane (1.22 mL, 9.6 mmol) and the resulting
mixture was stirred for 20 min. To this solution was added (103) (1
g, 3.2 mmol) in dichloromethane (10 mL) and the resulting mixture
was stirred for 60 min. The reaction mixture was washed with 10%
citric acid (20 mL) and the organic layer separated. The aqueous
layer was further extracted with ether (3.times.10 mL) and the
combined organic extracts were dried over MgSO.sub.4 then
concentrated in vacuo. Chromatography of the residue on silica gel,
eluting with hexane:ethyl acetate (4:1) to remove p-nitrophenol,
then further eluting with hexane:ethyl acetate (1:4) gave 780 mg
(72%) of the title compound. .sup.1H NMR (CDCl.sub.3, 400 MHz):
.delta. 0.91 (t, J=7.2 Hz, 3H), 1.04 (d, J=6.8 Hz, 3H), 1.12 (d,
J=6.8 Hz, 3H), 1.36-1.53 (m, 12H), 1.74 (m, 2H), 2.33 (s, 2H), 2.78
(m, 1H), 3.22 (m, 2H), 5.11 (m, 1H), 5.48 (t, 1H, NH). MS (ESI) m/z
342.24 (M+H.sup.+).
Step F:
1-{[(.alpha.-Isobutanoyloxybutoxy)carbonyl]aminomethyl}-1-Cyclohex-
ane Acetic Acid
[0507] To a solution of (104) (780 mg, 2.3 mmol) in dichloromethane
(20 mL) was added m-chloroperoxybenzoic acid (1.03 g, 4.6 mmol) and
NaHCO.sub.3 (386 mg, 4.6 mmol). After stirring for 16 h at room
temperature, another batch of m-chloroperoxybenzoic acid (791 mg,
4.6 mmol) and NaHCO.sub.3 (386 mg, 4.6 mmol) was added. The
resulting mixture was stirred for another 8 h and then treated with
10% citric acid. After filtration, the organic layer was separated,
dried over Na.sub.2SO.sub.4, and concentrated. The residue was
purified by reverse phase preparative HPLC to afford 79 mg (11%) of
the title compound. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 0.94
(t, J=7.2 Hz, 3H), 1.153 (d, J=7.2 Hz, 3H), 1.150 (d, J=7.2 Hz,
3H), 1.32-1.58 (m, 12H), 1.74 (m, 2H), 2.28 (s, 2H), 2.56 (m, 1H),
3.23 (m, 2H), 5.27 (t, J=6.8 Hz, 1H, NH), 6.71 (t, J=5.6 Hz, 1H).
MS (ESI) m/z 358.30 (M+H+).
[0508] The above acid was quantitatively converted to the
corresponding sodium salt by dissolving the acid in water (5 mL)
followed by addition of an equimolar quantity of 0.5 N NaHCO.sub.3
and lyophilization.
Example 29
Methyl
1-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cycloh-
exane Acetate (105)
Step A: Methyl
1-{[(.alpha.-Chloroisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetate (106)
[0509] A mixture of (93) (1.0 g, 3.3 mmol), benzene (90 mL), and
methanol (10 mL) was cooled to 0.degree. C.
Trimethylsilyldiazomethane was added slowly at 0.degree. C. until
the yellow color persisted. The mixture was stirred at 0.degree. C.
for 30 min until the reaction was complete (monitored by TLC).
After removing the solvent under reduced pressure, chromatography
of the resulting residue on silica gel, eluting with 10% ethyl
acetate/hexane gave 760 mg (72%) of the title compound. MS (ESI)
m/z 320.24 (M+H.sup.+).
Step B: Methyl
1-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexane
Acetate (105)
[0510] A mixture of (106) (760 mg, 2.38 mmol), silver carbonate
(394 mg, 1.4 mmol), and isobutyric acid (442 .mu.L, 4.76 mmol) in
chloroform was stirred at room temperature for 24 h. Another batch
of silver carbonate (394 mg, 1.4 mmol) and isobutyric acid (442
.mu.L, 4.76 mmol) was added, and the resulting mixture was stirred
for another 24 h. After filtration, the filtrate was concentrated
and the resulting residue purified by silica gel flash column
chromatography, eluting with 10% ethyl acetate/hexane, to afford
560 mg (63%) of the title compound. .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 0.94 (d, J=6.8 Hz, 3H), 0.96 (d, J=6.8 Hz, 3H), 1.15
(d, J=7.2 Hz, 3H), 1.17 (d, J=7.2 Hz, 3H), 1.32-1.58 (m, 10H), 2.01
(m, 1H), 2.19 (s, 2H), 2.55 (m, 1H), 3.18 (m, 2H), 3.67 (s, 3H),
5.33 (t, 1H), 6.56 (d, J=4.8 Hz, 1H). MS (ESI) m/z 372.38
(M+H+).
Example 30
Methyl
1-{[(.alpha.-Benzoyloxyisobutoxy)carbonyl]aminomethyl}-1-Cyclohexan-
e Acetate (107)
[0511] A mixture of
1-{[(.alpha.-benzoyloxyisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetic acid (84) (150 mg, 0.38 mmol), benzene (18 mL), and methanol
(2 mL) was cooled to 0.degree. C. Trimethylsilyldiazomethane was
added slowly at 0.degree. C. until the yellow color persisted. The
mixture was stirred at 0.degree. C. for 30 min until the reaction
was complete (monitored by TLC). After removing the solvent under
reduced pressure, chromatography of the residue on silica gel,
eluting with 5% ethyl acetate/hexane gave 98 mg (64%) of the title
compound. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 1.02 (d, J=6.4
Hz, 3H), 1.03 (d, J=6.4 Hz, 3H), 1.32-1.52 (m, 10H), 2.14 (m, 1H),
2.27 (s, 2H), 3.17 (m, 2H), 3.62 (s, 3H), 5.40 (t, 1H), 6.81 (d,
J=4.8 Hz, 1H), 7.40 (m, 2H), 7.54 (m, 1H), 8.12 (m, 2H). MS (ESI)
m/z 406.29 (M+H.sup.+).
Example 31
1-{[N-[(.alpha.-Isobutanoyloxyethoxy)carbonyl]-4-Bromophenylalaninyl]amino-
methyl}-1-Cyclohexane Acetic Acid (108)
Step A: 1-{(4-Bromophenylalaninyl)aminomethyl}-1-Cyclohexane
Acetate (109)
[0512] To a 40 mL vial was added an N-Boc-4-bromophenylalanine
(1.72 g, 5 mmol), dicyclohexylcarbodiimide (1.24 g, 6 mmol),
N-hydroxysuccinimide (0.7 g, 6 mmol), and acetonitrile (20 mL). The
reaction mixture was shaken at 25.degree. C. for 4 h. The
precipitated dicyclohexylurea was removed by filtration. To the
filtrate was added an aqueous solution (30 mL) of gabapentin
hydrochloride (1.04 g, 6 mmol), and sodium hydroxide (0.4 g, 10
mmol). The reaction was stirred at 22-25 C for 16 h. The reaction
mixture was diluted with ethyl acetate (100 mL) and washed with 0.5
M aqueous citric acid (2.times.100 mL) and water (2.times.100 mL).
The organic phase was separated, dried (MgSO.sub.4), filtered and
concentrated under reduced pressure. The residue was dissolved in
trifluoroacetic acid (40 mL) and allowed to stand at 22-25.degree.
C. for 2 h. The solvent was removed under reduced pressure. The
residue was dissolved in water (4 mL) and filtered through a 0.25
.mu.m nylon membrane filter prior to purification by preparative
HPLC (Phenomenex 250.times.21.2 mm, 5 .mu.m LUNA C18 column, 100%
water for 5 minutes, then 0-60% acetonitrile in water with 0.05%
TFA over 20 minutes at 20 mL/min). The pure fractions were combined
and the solvent was removed under reduced pressure to afford 1.7 g
(70%) of the title compound (109) as a white solid. MS (ESI) m/z
397.02, 399.01 (M+H+).
Step B:
1-{[N-[(.alpha.-Isobutanoyloxyethoxy)carbonyl]-4-Bromophenylalanin-
yl]aminomethyl}-1-Cyclohexane Acetic Acid (108)
[0513] To a stirred suspension of (109) (200 mg, 0.51 mmol) in
dichloromethane at 0.degree. C. was added triethylamine (141 .mu.L,
1.01 mmol) and trimethylchlorosilane (129 mL, 1.01 mmol). The
resulting mixture was stirred for 15 min at 0.degree. C., then a
solution of oa-isobutanoyloxyethyl-p-nitrophenyl carbonate (111)
(144 mg, 0.51 mmol) in dichloromethane was added. The mixture was
stirred at room temperature for 7 h (monitored by LC/MS) and then
the reaction mixture was diluted with dichloromethane and acidified
with citric acid. The organic layer was separated, washed with
brine, and dried over Na.sub.2SO.sub.4. After filtration and
concentration, the crude product was purified by preparative LC/MS
to afford 92 mg of the title compound. .sup.1H-NMR (CD.sub.3OD, 400
MHz): .delta. 1.10 (m, 6H), 1.46-1.25 (m, 13H), 2.20 (m, 2H), 2.48
(m, 1H), 2.84 (m, 1H), 3.06 (m, 1H), 3.17 (m, 1H), 4.36 (m, 1H),
6.67 (q, J=5.6 Hz, 1H), 7.17 (d, J=2.0, 8.0 Hz, 2H), 7.42 (dd,
J=2.0, 8.0 Hz, 2H).
Example 32
3-{[(.alpha.-Isobutanoyloxyethoxy)carbonyl]aminomethyl}-5-Methylhexanoic
Acid (110)
Step A: .alpha.-Isobutanoyloxyethyl-n-Nitrophenyl Carbonate
(111)
[0514] A solution of 1-chloroethyl-p-nitrophenyl carbonate (57)
(2.0 g, 8.14 mmol), and mercury isobutyrate (6.13 g, 16.29 mmol) in
dichloromethane (10 mL) was stirred at 45.degree. C. for 24 h. The
reaction was then cooled to room temperature and diluted with
hexane to precipitate mercury salts. The precipitate was filtered
through a pad of Celite, and the filtrate was concentrated in vacuo
to afford 2.5 g of crude product. Chromatography of the residue on
silica gel, eluting with a gradient of 10% dichloromethane/hexane
to 20% dichloromethane/hexane afforded 1.2 g (52%) of the title
compound. .sup.1H-NMR (CDCl.sub.3, 400 MHz): .delta. 1.21-1.99 (m,
6H), 1.62 (d, J=5.6 Hz, 3H), 2.61 (m, 1H), 6.84 (q, J=5.6 Hz, 1H),
7.41 (dt, J=6.8, 2.4 Hz, 2H), 8.29 (dt, J=6.8, 2.4 Hz, 2H).
Step B:
3-{[(.alpha.-Isobutanoyloxyethoxy)carbonyl]aminomethyl}-5-Methylhe-
xanoic Acid (110)
[0515] To a stirred suspension of pregabalin (2) (150 mg, 0.94
mmol) in anhydrous dichloromethane (10 mL) at 0.degree. C. was
added triethylamine (0.26 mL, 1.88 mmol) and trimethylchlorosilane
(0.24 mL, 1.88 mmol). After stirring for 15 min at 0.degree. C., a
solution of .alpha.-isobutanoyloxyethyl-p-nitrophenyl carbonate
(111) (267 mg, 0.94 mmol) in dichloromethane (3 mL) was added. The
resulting mixture was stirred at room temperature for 1.5 h. The
reaction mixture was acidified with citric acid and extracted with
dichloromethane. The combined organic extracts were washed with
brine and dried over Na.sub.2SO.sub.4. After filtration and
evaporation, the crude product was purified by silica gel
chromatography, eluting first with dichloromethane to remove
nitrophenol, then with 30% ethyl acetate in dichloromethane to
afford 130 mg (48%) of the title compound as a mixture of two
diastereomers. .sup.1H-NMR (CDCl.sub.3, 400 MHz): .delta. 0.90 (m,
6H), 1.70 (m, 8H), 1.46 (d, J=5.6 Hz, 3H), 1.66 (1H, m), 2.15 (m,
1H), 2.33 (m, 2H), 2.53 (m, 1H), 3.12 (m, 1H), 3.29 (m, 1H), 5.08
(t, J=6.0 Hz, 1H), 6.79 (m, 1H).
Example 33
3-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-5-Methyl-Hexano-
ic Acid
Step A: 1-Chloro-2-Methylpropyl-p-Nitrophenyl Carbonate (113)
[0516] To an ice cold reaction mixture containing p-nitrophenol
(4.06 g, 29 mmol) and 1-chloro-2-methylpropyl chloroformate (5.0 g,
29 mmol) in dichloromethane (200 mL) was added a solution of
pyridine (2.78 mL, 32 mmol) in dichloromethane (50 mL). The mixture
was stirred at 0.degree. C. for 30 min and then at room temperature
for 1 h. After evaporation of the solvent under reduced pressure,
the residue was dissolved in ether and washed with water, 10%
citric acid and water again. The ether layer was separated, dried
over Na.sub.2SO.sub.4 and evaporated under reduced pressure to give
7.9 g (100%) of the title compound as an off-white solid. .sup.1H
NMR (CDCl.sub.3, 400 MHz): .delta. 1.12 (d, J=6.6 Hz, 3H), 1.13 (d,
J=6.6 Hz, 3H), 2.29 (m, 1H), 6.24 (d, J=4.8 Hz, 1H), 7.42 (d, J=9.2
Hz, 2H), 8.28 (d, J=9.2 Hz, 2H).
Step B: .alpha.-Isobutanoyloxyisobutyl-p-Nitrophenyl Carbonate
(114)
[0517] Following the procedure for preparation of (111), and
substituting (113) for (57), provided the title compound in 15%
yield with a 70% recovery of starting material. .sup.1H-NMR
(CDCl.sub.3, 400 MHz): .delta. 1.07 (d, J=6.8 Hz), 1.21 (m, 6H),
2.18 (m, 1H), 2.26 (m, 1H), 6.60 (d, J=5.2 Hz, 1H), 7.42 (m, 2H),
8.28 (m, 2H).
Step C:
3-{[(.alpha.-Isobutanoyloxyisobutoxy)carbonyl]aminomethyl}-5-Methy-
l-Hexanoic Acid (112)
[0518] Following the procedure of preparation for (110), and
substituting (114) for (111), provided the title compound as a
mixture of two diastereomers in 51% yield. .sup.1H-NMR (CDCl.sub.3,
400 MHz): .delta. 0.89 (m, 12H), 1.17 (m, 8H), 1.65 (m, 1H), 2.02
(m, 1H), 2.16 (m, 1H), 2.33 (m, 2H), 2.56 (m, 1H), 3.13 (m, 1H),
3.30 (m, 1H), 5.00 (m, 1H), 6.57-6.56 (m, 1H).
Example 34
3-{[(.alpha.-Benzoyloxyisobutoxy)carbonyl]aminomethyl}-5-Methyl-Hexanoic
Acid (115)
Step A: .alpha.-Benzoyloxyisobutyl-p-Nitrophenyl Carbonate
(116)
[0519] Following the procedure of preparation for (111),
substituting (113) for (57) and mercury benzoate for mercury
isobutyrate, provided the title compound in 11% yield with a 50%
recovery of starting material. .sup.1H-NMR (CDCl.sub.3, 400 MHz):
.delta. 1.15 (d, J=3.2 Hz, 3H), 1.16 (d, J=3.2 Hz, 3H), 2.30 (m,
1H), 6.87 (d, J=4.4 Hz, 1H), 7.42 (dd, J=7.2, 2.0 Hz, 2H), 7.48 (t,
J=7.6 Hz, 2H), 7.62 (t, J=7.6 Hz, 1H), 8.09 (dd, J=8.0, 1.0 Hz,
2H), 8.27 (dd, J=7.2, 2.0 Hz, 2H).
Step B:
3-{[(.alpha.-Benzoyloxyisobutoxy)carbonyl]aminomethyl}-5-Methyl-He-
xanoic Acid (115)
[0520] Following the procedure of preparation for (110), and
substituting (116) for (111), provided the title compound as a
mixture of two diastereomers in 58% yield. .sup.1H-NMR (CDCl.sub.3,
400 MHz): .delta. 0.87 (m, 6H), 1.05 (m, 6H), 1.16 (m, 2H), 1.64
(m, 1H), 2.17 (m, 2H), 2.32 (m, 2H), 3.12 (m, 1H), 3.29 (m, 1H),
5.01 (br s, 1H), 6.82 (m, 1H), 7.44 (m, 2H), 7.57 (m, 1H), 8.05 (m,
2H).
Example 35
1-{[((5-Methyl-2-Oxo-1,3-Dioxol-4-en-4-yl)methoxycarbonyl]aminomethyl}-1-C-
yclohexane Acetic Acid (117)
Step A: Benzyl 2-Diazo-3-Oxo-Butyric Acid (118)
[0521] To a solution of benzyl acetoacetate (5.0 g, 26.01 mmol) and
4-acetamido-benzenesulfonyl azide (6.25 g, 26.01 mmol) in
acetonitrile (200 mL) at 0.degree. C. was dropwise added
triethylamine (10.9 mL, 78.03 mmol). The resulting mixture was
stirred for 30 min at 0.degree. C. and 4 h at room temperature.
After concentrating under reduced pressure, the residue was
triturated with 2:1 ethyl ether/petroleum ether (3.times.100 mL).
The combined organic extract was filtered through a pad of Celite
topped with silica gel. Removal of the solvent under reduced
pressure afforded 4.74 g of the title compound as off-white
crystals. .sup.1H-NMR (CDCl.sub.3, 400 MHz): .delta. 2.49 (s, 3H),
5.27 (s, 2H), 7.38 (m, 5H).
Step B: Benzyl 2-Hydroxy-3-Oxo-Butyric Acid (119)
[0522] A solution of the diazo compound (118) (4.74 g, 21.74 mmol)
in THF (110 mL) and H.sub.2O (50 mL) was heated under reflux with
Rh.sub.2(OAc).sub.2 (77 mg, 0.17 mmol) for 4 h and allowed to cool
to room temperature. The mixture was concentrated in vacuo and the
aqueous residue was extracted with ethyl acetate. The combined
organic extracts were washed with brine, dried over
Na.sub.2SO.sub.4, filtered and concentrated in vacuo to provide 4.5
g of crude product. .sup.1H-NMR (CDCl.sub.3, 400 MHz): .delta. 2.28
(s, 3H), 3.90 (s, 1H), 4.82 (s, 1H), 5.26 (m, 2H), 7.37 (m,
5H).
Step C: 4-Benzyloxycarbonyl 5-Methyl-2-Oxo-1,3-Dioxol-4-ene
(120)
[0523] To a suspension of carbonyldiimidazole (6.88 g, 42.45 mmol)
in THF (50 mL) at 0.degree. C. was added a solution of alcohol
(119) (4.50 g, 21.22 mmol) in dry THF (50 mL). The resulting
mixture was stirred for 5 h at 0.degree. C., then overnight at room
temperature. The mixture was concentrated in vacuo and the residue
was partitioned with water and ethyl acetate/hexane. The organic
layer was separated and washed with saturated NH.sub.4Cl, brine,
and dried over Na.sub.2SO.sub.4. After filtration and
concentration, the crude product was purified by flash
chromatography on silica gel, eluting with 20% ethyl acetate in
hexane to afford 2.6 g of the title compound. .sup.1H-NMR
(CDCl.sub.3, 400 MHz): .delta. 2.48 (s, 3H), 5.27 (s, 2H), 7.37
(br. s, 5H).
Step D: 5-Methyl-2-Oxo-1,3-Dioxol-4-enyl-4-Carboxlic Acid (121)
[0524] To a solution of compound (120) (2.6 g, 10.92 mmol) in 50 mL
of ethanol was added 260 mg of Pd/C (5%) and the resulting mixture
was stirred under a hydrogen atmosphere for 1 h. Filtration and
removal of solvent under reduced pressure provided 1.62 g of the
title compound. .sup.1H-NMR (CD.sub.3OD, 400 MHz): .delta. 2.41 (s,
3H).
Step E: 4-Hydroxymethyl-5-Methyl-2-Oxo-1,3-Dioxol-4-ene (122)
[0525] To a solution of the acid (121) (1.62 g, 11.10 mmol) and
anhydrous DMF (112 .mu.L) in dry dichloromethane (50 mL) at
0.degree. C. was dropwise added oxalyl chloride (6.1 mL of 2M
solution, 12.2 mmol). After stirring for 30 min at 0.degree. C. and
1 h at room temperature, the solvent was removed under reduced
pressure. The residue was dissolved in anhydrous dichloromethane
(65 mL) and cooled to -78.degree. C. To this solution was dropwise
added a solution of Bu.sub.4NBH.sub.4 (3.14 g, 12.2 mmol, in 20 mL
dichloromethane) over 10 min. After stirring for 1 h at -78.degree.
C., the mixture was cautiously quenched with 0.1N HCl (30 mL) and
allowed to warm to room temperature. The aqueous layer was
separated and was extracted with EtOAc (3.times.50 mL) and the
combined organic extract was washed with brine and dried over
Na.sub.2SO.sub.4. After removing the solvent under reduced
pressure, column chromatography on silica gel, eluting with 50%
EtOAc in dichloromethane provided 767 mg of the title compound.
.sup.1H-NMR (CD.sub.3OD, 400 MHz): .delta. 2.09 (s, 3H), 4.34 (s,
2H).
Step F: Benzyl
1-{[((5-Methyl-2-Oxo-1,3-Dioxol-4-en-4-yl)methoxy)carbonyl]-aminomethyl}--
1-Cyclohexane Acetate (123)
[0526] A suspension of the alcohol (122) (767 mg, 5.9 mmol) and
benzyl 1-isocyanatomethyl-1-cyclohexane acetate (5.9 mmol) in
toluene was refluxed overnight. After removing the solvent under
reduced pressure, the residue was purified by flash column
chromatography, eluting with 30% EtOAc in hexane to provide 510 mg
of the title compound. .sup.1H-NMR (CD.sub.3OD, 400 MHz): .delta.
1.58-1.30 (m, 10H), 2.18 (s, 3H), 2.35 (s, 2H), 3.17 (d, J=6.8 Hz,
2H), 4.80 (s, 2H), 5.11 (s, 2H), 5.44 (t, J=6.8 Hz, 1H), 7.36 (m,
5H).
Step G:
1-{[((5-Methyl-2-Oxo-1,3-Dioxol-4-en-4-yl)methoxy)carbonyl]-aminom-
ethyl}-1-Cyclohexane Acetic Acid (117)
[0527] To a solution of compound (123) (510 mg, 1.41 mmol) in
ethanol (20 mL) was added 59 mg of Pd/C (5%) and the resulting
mixture was stirred under a hydrogen atmosphere for 1 h. Filtration
and removal of volatiles under reduced pressure provided the crude
product, which was purified by preparative LC/MS to provide 105 mg
of the title compound. .sup.1H-NMR (CD.sub.3OD, 400 MHz): .delta.
1.52-1.36 (m, 10H), 2.16 (s, 3H), 2.27 (s, 2H), 3.22 (s, 2H), 4.86
(s, 2H).
Example 36
Piperidinium
1-{(1-Methyl-3-Oxo-But-1-enyl)aminomethyl}-1-Cyclohexane Acetate
(124)
[0528] 2,4-pentanedione (103 .mu.L, 1 mmol), gabapentin (171 mg, 1
mmol), and piperidine (99 .mu.L, 1 mmol) were mixed in anhydrous
methanol (10 mL). The resulting mixture was heated under reflux for
4 h. Removal of the solvent under reduced pressure gave the title
compound with purity greater than 90%. .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 1.34-1.62 (m, 12H), 1.71 (m, 4H), 1.94 (s, 3H), 1.96
(s, 3H), 2.26 (s, 2H), 2.98 (m, 4H), 3.38 (d, J=6 Hz, 2H), 4.90 (s,
1H), 5.20 (s, br, 2H), 8.64 (t, J=6 Hz, 1H). MS (ESI) m/z 252.35
(M-H.sup.-).
Example 37
Piperidinium
1-{1-[(2-Oxo-Tetrahydrofuran-3-ylidene)ethyl]aminomethyl}-1-Cyclohexane
Acetate (125)
[0529] 2-Acetylbutyrolactone (108 .mu.L, 1 mmol), gabapentin (171
mg, 1 mmol), and piperidine (99 .mu.L, 1 mmol) were mixed in
anhydrous methanol (10 mL). After heating under reflux for 6 h, the
solvent was removed under reduced pressure to afford the title
compound with purity greater than 90%. .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 1.34-1.62 (m, 12H), 1.71 (m, 4H), 1.94 (s, 3H), 2.24
(s, 2H), 2.81 (t, J=7.6 Hz, 2H), 2.99 (m, 4H), 3.31 (d, J=6.4 Hz,
2H), 4.23 (t, J=7.6 Hz, 2H), 5.17 (s, br, 2H), 8.64 (t, J=6.4 Hz,
1H). MS (ESI) m/z 280.34 (M-H.sup.-).
Example 38
Piperidinium
1-{(2-Carbomethoxy-Cyclopent-1-enyl)aminomethyl}-1-Cyclohexane
Acetate (126)
[0530] Methyl 2-oxocyclopentanecarboxylate (124 .mu.L, 1 mmol),
gabapentin (171 mg, 1 mmol), and piperidine (99 .mu.L, 1 mmol) were
mixed in anhydrous methanol (10 mL). After heating under reflux for
16 h, the solvent was removed under reduced pressure to afford the
title compound with purity greater than 90%. .sup.1H NMR
(CDCl.sub.3, 400 MHz): .delta. 1.29-1.60 (m, 12H), 1.72 (m, 4H),
1.79 (m, J=7.6 Hz, 2H), 2.24 (s, 2H), 2.49 (t, J=7.6 Hz, 2H), 2.55
(t, J=7.6 Hz, 2H), 2.99 (m, 4H), 3.24 (d, J=6.8 Hz, 2H), 3.63 (s,
3H), 5.06 (s, br, 2H), 7.93 (s, br, 1H). MS (ESI) m/z 294.36
(M-H.sup.-).
Example 39
Piperidinium
1-{(1-Methyl-2-(Ethoxycarbonyl-3-Ethoxy-3-Oxoprop-1-enyl)aminomethyl}-1-C-
yclohexane Acetate (127)
[0531] Diethyl acetylmalonate (202 mg, 1 mmol), gabapentin (171 mg,
1 mmol), and piperidine (99 .mu.L, 1 mmol) were mixed in anhydrous
ethanol (10 mL). After heating under reflux for 16 h, the solvent
was removed under reduced pressure to give the title compound with
purity greater than 90%. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta.
1.28 (t, J=7.2 Hz, 6H), 1.38-1.64 (m, 12H), 1.75 (m, 4H), 1.96 (s,
3H), 2.23 (s, 2H), 2.99 (m, 4H), 3.24 (d, J=5.2 Hz, 2H), 4.20 (q,
J=7.2 Hz, 4H), 4.35 (s, br, 2H), 7.79 (t, J=5.2 Hz, 1H). MS (ESI)
m/z 354.38 (M-H.sup.-).
Example 40
1-{[(.alpha.-2-(2-(2-Methyl-1,3-Dioxolan-2-yl)carboxyisobutoxy)carbonyl]-a-
minomethyl}-1-Cyclohexane Acetic Acid (128)
Step A: 2-Methyl-1,3-Dioxolane-2-Carboxylic Acid (129)
[0532] To a stirred mixture containing ethyl pyruvate (11.1 mL, 0.1
mol) and ethylene glycol (5.6 mL, 0.1 mol) in anhydrous
dichloromethane (100 mL) at 0.degree. C. was added boron
trifluoride dietherate (6.4 mL, 0.05 mol) and catalytic amount of
acetic acid. The resulting mixture was stirred at 40.degree. C. for
16 h and then diluted with 100 mL of dichloromethane. The organic
solution was washed successively with saturated sodium chloride
solution (2.times.80 mL). The organic layer was separated and the
combined organic extracts were concentrated. The residue was
treated with 1N sodium hydroxide at room temperature. After
stirring at room temperature for 3 h (monitored by TLC), citric
acid was added to adjust the pH to 4. The product was extracted
with dichloromethane, dried over Na.sub.2SO.sub.4 and concentrated
to afford 5.1 g (38%) of the title compound (129) as a clear
liquid. This material was used in the next reaction without further
purification. .sup.1H NMR (CDCl.sub.3, 400 MHz): .delta. 1.55 (s,
3H), 4.03 (m, 4H).
Step B: Benzyl
1-{[(.alpha.-(2-(2-Methyl-1,3-Dioxolan-2-yl)carboxyisobutoxy)carbonyl]ami-
nomethyl}-1-Cyclohexane Acetate (130)
[0533] A mixture containing benzyl
1-{[(.alpha.-chloroisobutoxy)carbonyl]aminomethyl}-1-cyclohexane
acetate (95) (1 g, 2.53 mmol), (129) (673 mg, 5.1 mmol), silver
carbonate (557 mg, 2.53 mmol), and triethylamine (709 .mu.L, 5.1
mmol) in chloroform was stirred at room temperature for 16 h. After
filtration, the filtrate was concentrated. The resulting residue
was purified by silica gel chromatography, eluting with 15% ethyl
acetate/hexane to afford 510 mg (41%) of the title compound (130).
MS (ESI) m/z 492.40 (M+H+).
Step C:
1-{[(.alpha.-(2-(2-Methyl-13-Dioxolan-2-yl)carboxyisobutoxy)carbon-
yl]-aminomethyl}-1-Cyclohexane Acetic Acid (128
[0534] A mixture of (130) (470 mg, 0.96 mmol) and 5% Pd--C
(catalytic amount) in ethanol was stirred under hydrogen at room
temperature for 16 h. Filtration and concentration gave 382 mg
(100%) of the title compound (128). .sup.1H NMR (CDCl.sub.3, 400
MHz): .delta. 0.96 (d, J=6.8 Hz, 3H), 0.97 (d, J=6.8 Hz, 3H),
1.32-1.58 (m, 10H), 1.59 (s, 3H), 2.06 (m, 1H), 2.32 (s, 2H), 3.26
(m, 2H), 4.08 (m, 4H), 5.29 (t, 1H, NH), 6.55 (d, J=4.8 Hz, 1H). MS
(ESI) m/z 402.32 (M+H.sup.+).
[0535] The acid form was quantitatively converted to its
corresponding sodium salt by dissolution in water (5 mL), addition
of an equimolar quantity of 0.5 N NaHCO.sub.3, followed by
lyophilization.
Example 41
In Vitro Determination of Caco-2 Cellular Permeability of
Prodrugs
[0536] The passive permeability of the prodrugs of the current
invention may be assessed in vitro using standard methods well
known in the art (See, e.g., Stewart, et al., Pharm. Res., 1995,
12, 693). For example, passive permeability may be evaluated by
examining the flux of a prodrug across a cultured polarized cell
monolayer (e.g., Caco-2 cells). Caco-2 cells obtained from
continuous culture (passage less than 28) were seeded at high
density onto Transwell polycarbonate filters. Cells were maintained
with DMEM/10% fetal calf serum+0.1 mM nonessential amino acids+2 mM
L-Gln, 5% CO.sub.2/95% 0.sub.2, 37.degree. C. until the day of the
experiment. Permeability studies were conducted at pH 6.5 apically
(in 50 mM MES buffer containing 1 mM CaCl.sub.2, 1 mM MgCl.sub.2,
150 mM NaCl, 3 mM KCl, 1 mM NaH.sub.2PO4, 5 mM glucose) and pH 7.4
basolaterally (in Hanks' balanced salt solution containing 10 mM
HEPES) in the presence of efflux pump inhibitors (250 .mu.M MK-571,
250 uM Verapamil, 1 mM Ofloxacin). Inserts were placed in 12 or 24
well plates containing buffer and incubated for 30 min at
37.degree. C. Prodrug (200 .mu.M) was added to the apical or
basolateral compartment (donor) and concentrations of prodrug
and/or released parent drug in the opposite compartment (receiver)
were determined at intervals over 1 hour using LC/MS/MS. Values of
apparent permeability (P.sub.app) were calculated using the
equation:
P.sub.app=V.sub.r(dC/dt)/(AC.sub.o)
[0537] Here V.sub.r is the volume of the receiver compartment in
mL; dC/dt is the total flux of prodrug and parent drug (.mu.M/s),
determined from the slope of the plot of concentration in the
receiver compartment versus time; C.sub.o is the initial
concentration of prodrug in .mu.M; A is the surface area of the
membrane in cm.sup.2. Preferably, prodrugs with significant
transcellular permeability demonstrate a value of P.sub.app of
.gtoreq.1.times.10.sup.-6 cm/s and more preferably, a value of Pa
of >1.times.10.sup.-5 cm/s, and still more preferably a value of
P.sub.app of 5.times.10.sup.-5 cm/s. Typical values of P, obtained
for prodrugs of GABA analogs are shown in the following table:
TABLE-US-00001 P.sub.app (apical to P.sub.app (basolateral to Ratio
Compound basolateral) (cm/s) apical) (cm/s) A-B/B-A (51) 1.06
.times. 10.sup.-4 1.25 .times. 10.sup.-5 8.5 (56) 3.1 .times.
10.sup.-5 2.0 .times. 10.sup.-6 15.5 (62) 2.10 .times. 10.sup.-5
6.40 .times. 10.sup.-6 3.3 (68) 8.43 .times. 10.sup.-5 2.26 .times.
10.sup.-5 3.7 (69) 1.84 .times. 10.sup.-4 5.22 .times. 10.sup.-6
35.2 (70) 1.78 .times. 10.sup.-5 1.68 .times. 10.sup.-6 10.6 (71)
8.10 .times. 10.sup.-5 1.99 .times. 10.sup.-5 4.1 (72) 2.51 .times.
10.sup.-5 1.26 .times. 10.sup.-6 2.0 (77) 7.41 .times. 10.sup.-5
1.43 .times. 10.sup.-5 5.2 (78) 1.37 .times. 10.sup.-4 2.46 .times.
10.sup.-5 5.6 (80) 6.62 .times. 10.sup.-5 8.75 .times. 10.sup.-6
7.6 (81) 8.65 .times. 10.sup.-5 1.27 .times. 10.sup.-5 6.8 (82)
1.25 .times. 10.sup.-4 1.82 .times. 10.sup.-5 6.9 (83) 1.29 .times.
10.sup.-5 4.48 .times. 10.sup.-5 0.3 (84) 1.26 .times. 10.sup.-4
1.57 .times. 10.sup.-5 8.1 (89) 5.85 .times. 10.sup.-5 2.34 .times.
10.sup.-6 25.0 (90) 9.22 .times. 10.sup.-5 5.75 .times. 10.sup.-6
16.0
[0538] The data in this table shows that the prodrugs disclosed
herein have high cellular permeability and should be well absorbed
from the intestine. With the exception of compound (83), the
apical-to-basolateral permeabilities of these prodrugs exceed their
basolateral-to-apical permeabilities. This suggests that these
compounds may be substrates for active transport mechanisms present
in the apical membrane of Caco cells (though some component of this
transcellular permeability may also be mediated by passive
diffusion). The greater basolateral-to-apical permeability of (83)
suggests that this compound may be subject to efflux across the
basolateral membrane, despite the presence of the efflux pump
inhibitors MK-571, verapamil and ofloxacin.
Example 42
Uptake of Gabapentin Following Administration of Gabapentin or
Gabapentin Prodrugs Intracolonically in Rats
[0539] Sustained release oral dosage forms, which release drug
slowly over periods of 6-24 hours, generally release a significant
proportion of the dose within the colon. Thus drugs suitable for
use in such dosage forms preferably exhibit good colonic
absorption. This experiment was conducted to assess the suitability
of gabapentin prodrugs for use in an oral sustained release dosage
form.
Step A: Administration Protocol
[0540] Rats were obtained commercially and were pre-cannulated in
the both the ascending colon and the jugular vein. Animals were
conscious at the time of the experiment. All animals were fasted
overnight and until 4 hours post-dosing. Gabapentin or gabapentin
prodrugs (59), (63), (69), (72), (77), (79), (85), (117) and (126)
were administered as a solution (in water or PEG 400) directly into
the colon via the cannula at a dose equivalent to 25 mg of
gabapentin per kg. Blood samples (0.5 mL) were obtained from the
jugular cannula at intervals over 8 hours and were quenched
immediately by addition of acetonitrile/methanol to prevent further
conversion of the prodrug. Blood samples were analyzed as described
below.
Step B: Sample Preparation for Colonic Absorbed Drug
[0541] 1. In blank 1.5 mL eppendorf tubes, 300 .mu.L of 50/50
acetonitrile/methanol and 20 .mu.L of p-chlorophenylalanine was
added as an internal standard. [0542] 2. Rat blood was collected at
different time points and immediately 100 .mu.L of blood was added
into the eppendorf tube and vortexed to mix. [0543] 3. 10 .mu.L of
a gabapentin standard solution (0.04, 0.2, 1, 5, 25, 100 .mu.g/mL)
was added to 90 .mu.L of blank rat blood to make up a final
calibration standard (0.004, 0.02, 0.1, 0.5, 2.5, 10 .mu.g/mL).
Then 300 .mu.L of 50/50 acetonitrile/methanol was added into each
tube followed by 20 .mu.L of p-chlorophenylalanine. [0544] 4.
Samples were vortexed and centrifuged at 14,000 rpm for 10 min.
[0545] 5. Supernatant was taken for LC/MS/MS analysis.
Step C: LC/MS/MS Analysis
[0546] An API 2000 LC/MS/MS spectrometer equipped with Shidmadzu
10ADVp binary pumps and a CTC HTS-PAL autosampler were used in the
analysis. A Zorbax XDB C8 4.6.times.150 mm column was heated to
45.degree. C. during the analysis. The mobile phase was 0.1% formic
acid (A) and acetonitrile with 0.1% formic acid (B). The gradient
condition was: 5% B for 1 min, then to 98% B in 3 min, then
maintained at 98% B for 2.5 min. The mobile phase was returned to
5% B for 2 min. A TurbolonSpray source was used on the API 2000.
The analysis was done in positive ion mode and an MRM transition of
172/137 was used in the analysis of gabapentin (MRM transitions
426/198 for (59), 364/198 for (63), 392/198 for (69), 316/198 for
(72), 330/198 for (77), 330/198 for (79), 316/198 for (85) and
327.7/153.8 for (117) were used). 20 .mu.L of the samples were
injected. The peaks were integrated using Analyst 1.1 quantitation
software. Following colonic administration of each of these
prodrugs, the maximum plasma concentrations of gabapentin
(C.sub.max), as well as the area under the gabapentin plasma
concentration vs. time curves (AUC) were significantly greater
(>2-fold) than that produced from colonic administration of
gabapentin itself. For example, prodrug (77) provided both
gabapentin C.sub.max and AUC values greater than 10-fold higher
than gabapentin itself. This data demonstrates that compounds of
the invention may be formulated as compositions suitable for
enhanced absorption and/or effective sustained release of GABA
analogs to minimize dosing frequency due to rapid systemic
clearance of these GABA analogs.
Example 43
Sustained Release of Gabapentin Following Prodrug Administration
Using Osmotic Mini-Pump Devices in Beagle Dogs
[0547] Gabapentin or the gabapentin prodrugs (77) and (82) (at a
dose equivalent to 10 mg of gabapentin per kg) were dissolved in a
suitable solvent (e.g., water, PEG 400, etc.) and filled into
preweighed Alzet.RTM. mini-osmotic pump devices (Model 2001D)
(Durect Corp., Cupertino, Calif.). The filled Alzets were
pre-equilibrated by soaking in isotonic saline at 37.degree. C. for
3 hours and stored in sealed containers at 4.degree. C. overnight.
Alzets were then administered orally to four fasted male beagle
dogs (approx. 6.5 kg). Animals were fed at 4 hr after each dose.
Blood samples (1.0 mL) were withdrawn at intervals over 48 hours
and processed immediately for plasma. Plasma samples were frozen
and stored at -80.degree. C. until analyzed using the method
described above. Both prodrugs afforded gabapentin concentrations
in plasma at 12 hours post-dosing that were greater than 2-fold the
concentration of gabapentin seen following administration of
gabapentin itself in the Alzet device. This data further confirms
that compounds of the invention may be formulated as compositions
suitable for effective sustained release of GABA analogs.
Example 44
Uptake of Pregabalin Following Administration of Pregabalin or
Pregabalin Prodrugs Intracolonically in Rats
[0548] The protocol of Example 41 was repeated with pregabalin and
the pregabalin prodrugs (110) and (112). Following colonic
administration of each of these prodrugs, the maximum plasma
concentrations of pregabalin (C.sub.max), as well as the area under
the pregabalin plasma concentration vs. time curves (AUC) were
significantly greater (>2-fold) than that produced from colonic
administration of pregabalin itself.
[0549] Finally, it should be noted that there are alternative ways
of implementing the present invention. Accordingly, the present
embodiments are to be considered as illustrative and not
restrictive, and the invention is not to be limited to the details
given herein, but may be modified within the scope and equivalents
of the appended claims.
[0550] All publications and patents cited herein are incorporated
by reference in their entirety.
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