U.S. patent application number 14/134264 was filed with the patent office on 2014-09-18 for 8-carboxamido-2,6-methano-3-benzazocines.
This patent application is currently assigned to Rensselaer Polytechnic Institute. The applicant listed for this patent is Rensselaer Polytechnic Institute. Invention is credited to Mark P. WENTLAND.
Application Number | 20140275545 14/134264 |
Document ID | / |
Family ID | 22922766 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140275545 |
Kind Code |
A1 |
WENTLAND; Mark P. |
September 18, 2014 |
8-CARBOXAMIDO-2,6-METHANO-3-BENZAZOCINES
Abstract
8-Substituted-2,6-methano-3-benzazocines of general structure I
in which A is --CH.sub.2--OH, --CH.sub.2NH.sub.2,
--NHSO.sub.2CH.sub.3, ##STR00001## and Y is O, S or NOH are useful
as analgesics, anti-diarrheal agents, anticonvulsants, antitussives
and anti-addiction medications. ##STR00002## 8-Carboxamides,
thiocarboxamides, hydroxyamidines and formamides are preferred.
Inventors: |
WENTLAND; Mark P.;
(Watervliet, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rensselaer Polytechnic Institute |
Troy |
NY |
US |
|
|
Assignee: |
Rensselaer Polytechnic
Institute
Troy
NY
|
Family ID: |
22922766 |
Appl. No.: |
14/134264 |
Filed: |
December 19, 2013 |
Related U.S. Patent Documents
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Application
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Patent Number |
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13556650 |
Jul 24, 2012 |
8642615 |
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14134264 |
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13103599 |
May 9, 2011 |
8252929 |
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13556650 |
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12249238 |
Oct 10, 2008 |
7956187 |
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13103599 |
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11205354 |
Aug 17, 2005 |
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12249238 |
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10987527 |
Nov 12, 2004 |
7265226 |
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11205354 |
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Current U.S.
Class: |
546/37 ; 546/46;
546/74; 546/97 |
Current CPC
Class: |
A61P 17/04 20180101;
A61P 25/04 20180101; A61K 31/485 20130101; A61P 25/32 20180101;
A61P 1/06 20180101; A61P 3/04 20180101; A61P 43/00 20180101; C07D
221/26 20130101; A61P 25/36 20180101; C07D 489/12 20130101; A61P
11/00 20180101; C07D 489/10 20130101; A61P 25/14 20180101; C07D
491/18 20130101; C07D 221/22 20130101; A61P 13/02 20180101; A61P
25/34 20180101; A61P 1/00 20180101; A61P 25/28 20180101; A61P 25/02
20180101; C07D 489/00 20130101; A61P 1/12 20180101; A61P 25/30
20180101; C07D 401/04 20130101; C07D 405/06 20130101; C07D 489/02
20130101; A61P 29/00 20180101; C07D 489/08 20130101; A61P 9/10
20180101; A61P 25/00 20180101; A61P 25/08 20180101; A61P 37/06
20180101; A61P 3/00 20180101; A61P 11/14 20180101 |
Class at
Publication: |
546/37 ; 546/97;
546/46; 546/74 |
International
Class: |
C07D 489/02 20060101
C07D489/02; C07D 221/22 20060101 C07D221/22 |
Goverment Interests
STATEMENT AS TO RIGHTS UNDER FEDERALLY-SPONSORED RESEARCH
[0002] This invention was made with Government support under
Contract No. R01 DA12180, awarded by the National Institutes of
Health. Accordingly, the U.S. Government has certain rights in this
invention.
Claims
1. A compound of formula: ##STR00034## wherein A is chosen from
##STR00035## Q is chosen from O, S and NR.sup.17; Y is chosen from
O, S, NR.sup.17 and NOH; R.sup.1 is chosen from hydrogen, lower
alkoxy, phenyl and --NHR.sup.8; R.sup.2 and R.sup.2a are both
hydrogen or taken together R.sup.2 and R.sup.2a are .dbd.O; R.sup.3
is chosen from hydrogen, lower alkyl, alkenyl, aryl, heterocyclyl,
benzyl and hydroxyalkyl; R.sup.4 is chosen from hydrogen, hydroxy,
amino, lower alkoxy, C.sub.1-C.sub.20 alkyl and C.sub.1-C.sub.20
alkyl substituted with hydroxy or carbonyl; R.sup.5 is lower alkyl;
R.sup.6 is lower alkyl; R.sup.7 is chosen from hydrogen and
hydroxy; or together R.sup.4, R.sup.5, R.sup.6 and R.sup.7 may form
from one to three rings, said rings having optional additional
substitution; R.sup.8 is chosen from hydrogen, --OH, --NH.sub.2 and
--CH.sub.2R.sup.15; R.sup.15 is chosen from hydrogen, alkyl, aryl,
substituted aryl and alkyl substituted with alkoxy, amino,
alkylamino or dialkylamino; R.sup.16 is chosen from hydrogen and
NH.sub.2; and R.sup.17 is chosen from hydrogen, alkyl, aryl and
benzyl.
2. A compound according to claim 1 wherein A is chosen from the
group consisting of: --COOCH.sub.3, --COOEt, --CONH.sub.2,
--C(.dbd.S)NH.sub.2, --C(O)NHOH, --C(O)NHNH.sub.2, --CONHCH.sub.3,
--CONHBn, --CONHCH.sub.2(4-MeOC.sub.6H.sub.4), C(.dbd.NOH)NH.sub.2,
C(.dbd.NOH)C.sub.6H.sub.5, --NHCHO and --NHCHS.
3. A compound according to claim 1 selected from: ##STR00036##
wherein R.sub.17 is selected from --CH.sub.2-c-C.sub.3H.sub.5,
--CH.sub.2CH.dbd.CH.sub.2, --CH.sub.2CH.dbd.C(CH.sub.3).sub.2,
.sup.-CH.sub.3; ##STR00037## ##STR00038##
4. A method of treating a disease or condition selected from pain,
pruritus, diarrhea, cough, drug addiction, hyperalgesia,
respiratory depression, dyskinesia, gastrointestinal motility
disorders, and irritable bowel syndrome comprising the step of
administering to a subject in need thereof a compound of formula:
##STR00039## wherein A is chosen from ##STR00040## Q is chosen from
O, S and NR.sup.17; Y is chosen from O, S, NR.sup.17 and NOH; Z is
chosen from OH, SH, CN and NH.sub.2; R.sup.1 is chosen from
hydrogen, lower alkoxy, phenyl and --NHR.sup.8; R.sup.2 and
R.sup.2a are both hydrogen or taken together R.sup.2 and R.sup.2a
are .dbd.O; R.sup.3 is chosen from hydrogen, lower alkyl, alkenyl,
aryl, heterocyclyl, benzyl and hydroxyalkyl; R.sup.4 is chosen from
hydrogen, hydroxy, amino, lower alkoxy, C.sub.1-C.sub.20 alkyl and
C.sub.1-C.sub.20 alkyl substituted with hydroxy or carbonyl;
R.sup.5 is lower alkyl; R.sup.6 is lower alkyl; R.sup.7 is chosen
from hydrogen and hydroxy; or together R.sup.4, R.sup.5, R.sup.6
and R.sup.7 may form from one to three rings, said rings having
optional additional substitution; R.sup.8 is chosen from hydrogen,
--OH, --NH.sub.2 and --CH.sub.2R.sup.15; R.sup.15 is chosen from
hydrogen, alkyl, aryl, substituted aryl and alkyl substituted with
alkoxy, amino, alkylamino or dialkylamino; R.sup.16 is chosen from
hydrogen and NH.sub.2; and R.sup.17 is chosen from hydrogen, alkyl,
aryl and benzyl.
5. The method according to claim 4 wherein A is chosen from the
group consisting of: --COOCH.sub.3, --COOEt, --CONH.sub.2,
--C(.dbd.S)NH.sub.2, --C(O)NHOH, --C(O)NHNH.sub.2, --CONHCH.sub.3,
--CONHBn, --CONHCH.sub.2(4-MeOC.sub.6H.sub.4),
--C(.dbd.NOH)NH.sub.2, -C(=NOH)C.sub.6H.sub.5, --NHCHO and
-NHCHS.
6. The method according to claim 4 wherein said compound is
selected from: ##STR00041## wherein R.sub.17 is selected from
--CH.sub.2-c-C.sub.3H.sub.5, --CH.sub.2CH.dbd.CH.sub.2,
--CH.sub.2CH.dbd.C(CH.sub.3).sub.2, --CH.sub.3; ##STR00042##
##STR00043##
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of copending U.S.
application Ser. No. 13/556,650, filed Jul. 24, 2012, now allowed,
which was a divisional of U.S. application Ser. No. 13/103,599,
filed May 9, 2011, now U.S. Pat. No. 8,252,929, which was a
continuation of U.S. application Ser. No. 12/249,238, filed Oct.
10, 2008, now U.S. Pat. No. 7,956,187, which was a divisional of
U.S. application Ser. No. 11/205,354, filed Aug. 17, 2005, now
abandoned, which was a divisional of U.S. application Ser. No.
10/987,527, filed Nov. 12, 2004, now U.S. Pat. No. 7,265,226, which
was a divisional of U.S. application Ser. No. 10/409,803, filed
Apr. 9, 2003, now U.S. Pat. No. 6,887,998, which was a divisional
of Ser. No. 10/305,287, filed Nov. 26, 2002, now U.S. Pat. No.
6,784,187. U.S. Ser. No. 10/305,287 was a continuation-in-part of
PCT International Application PCT/US01/045581, filed Oct. 31, 2001,
and published under PCT Article 21(2) in English as WO 02/36573 on
May 10, 2002. PCT/US01/045581 claimed benefit from United States
Provisional Application 60/244,438, filed Oct. 31, 2000. The entire
contents of each of the prior applications are incorporated herein
by reference.
FIELD OF THE INVENTION
[0003] The invention relates to opioid receptor binding compounds
containing carboxamides, formamides, thiocarboxamides and
hydroxyamidines. The compounds are useful as analgesics,
anesthetics, anti-diarrheal agents, anti-retroviral agents,
anticonvulsants, antitussives, anti-cocaine, and anti-addiction
medications.
BACKGROUND OF THE INVENTION
[0004] Opiates have been the subject of intense research since the
isolation of morphine in 1805, and thousands of compounds having
opiate or opiate-like activity have been identified. Many opioid
receptor-interactive compounds including those used for producing
analgesia (e.g., morphine) and those used for treating drug
addiction (e.g., naltrexone and cyclazocine) in humans have limited
utility due to poor oral bioavailability and a very rapid clearance
rate from the body. This has been shown in many instances to be due
to the presence of the 8-hydroxyl group (OH) of
2,6-methano-3-benzazocines, also known as benzomorphans [(e.g.,
cyclazocine and EKC (ethylketocyclazocine)] and the corresponding
3-OH group in morphinanes (e.g., morphine).
##STR00003##
[0005] The high polarity of these hydroxyl groups retards oral
absorption of the parent molecules. Furthermore, the 8-(or 3-)OH
group is prone to sulfonation and glucuronidation (Phase II
metabolism), both of which facilitate rapid excretion of the active
compounds, leading to disadvantageously short half-lives for the
active compounds. Unfortunately, the uniform experience in the art
of the past seventy years has been that removal or replacement of
the 8-(or 3-)OH group has lead to pharmacologically inactive
compounds.
SUMMARY OF THE INVENTION
[0006] We have now found that the 8-(or 3-)hydroxyl group may be
replaced by a number of small, polar, neutral residues, such as
carboxamide, thiocarboxamide, hydroxyamidine and formamide groups.
Not only do the benzomorphan, morphinan carboxamides have
unexpectedly high affinity for opioid receptors, compounds
containing these groups in place of OH are far less susceptible to
Phase II metabolism and are generally more orally bioavailable. The
compounds of the invention are therefore useful as analgesics,
anesthetics, anti-pruritics, anti-diarrheal agents,
anticonvulsants, antitussives, anorexics and as treatments for
hyperalgesia, drug addiction, respiratory depression, dyskinesia,
pain (including neuropathic pain), irritable bowel syndrome and
gastrointestinal motility disorders. Drug addiction, as used
herein, includes alcohol and nicotine addiction. There is evidence
in the literature that the compounds may also be useful as
anti-retroviral agents, immunosuppressants and antiinflammatories
and for reducing ischemic damage (and cardioprotection), for
improving learning and memory, and for treating urinary
incontinence.
[0007] In one aspect, the invention relates to
2,6-methano-3-benzazocine-8-carboxamides and
2,6-methano-3-benzazocine-8-carboxylate esters of formula:
##STR00004##
wherein
[0008] A is chosen from --CH.sub.2--Z, --CN,
--NHSO.sub.2-(loweralkyl),
##STR00005##
[0009] Q is chosen from O, S and NR.sup.17;
[0010] Y is chosen from O, S, NR.sup.17 and NOH;
[0011] Z is chosen from OH, SH, CN and NH.sub.2;
[0012] R.sup.1 is chosen from hydrogen, lower alkoxy, phenyl and
--NHR.sup.8;
[0013] R.sup.2 and R.sup.2a are both hydrogen or taken together
R.sup.2 and R.sup.2a are .dbd.O;
[0014] R.sup.3 is chosen from hydrogen, lower alkyl, alkenyl, aryl,
heterocyclyl, benzyl and hydroxyalkyl;
[0015] R.sup.4 is chosen from hydrogen, hydroxy, amino, lower
alkoxy, C.sub.1-C.sub.20 alkyl and C.sub.1-C.sub.20 alkyl
substituted with hydroxy or carbonyl;
[0016] R.sup.5 is lower alkyl;
[0017] R.sup.6 is lower alkyl;
[0018] R.sup.7 is chosen from hydrogen and hydroxy; or together
R.sup.4, R.sup.5, R.sup.6 and R.sup.7 may form from one to three
rings, said rings having optional additional substitution;
[0019] R.sup.8 is chosen from hydrogen, --OH, --NH.sub.2 and
--CH.sub.2R.sup.15;
[0020] R.sup.15 is chosen from hydrogen, alkyl, aryl, substituted
aryl and alkyl substituted with alkoxy, amino, alkylamino or
dialkylamino;
[0021] R.sup.16 is chosen from hydrogen and NH.sub.2; and
[0022] R.sup.17 is chosen from hydrogen, alkyl, aryl and benzyl;
with the provisos that, (1) when R.sup.2 and R.sup.2a are hydrogen,
R.sup.3 is hydrogen or cyclopropyl, R.sup.4 is hydroxy, and
together R.sup.5, R.sup.6 and R.sup.7 form two rings substituted
with a spirodioxolane, A cannot be --COOCH.sub.3 or
NHSO.sub.2CH.sub.3; (2) when R.sup.2 and R.sup.2a are hydrogen,
R.sup.3 is hydrogen or cyclopropyl, R.sup.4 is hydroxy, and
together R.sup.5, R.sup.6 and R.sup.7 form the ring system of
oxymorphone and naltrexone, A cannot be NHSO.sub.2CH.sub.3; (3)
when R.sup.2, R.sup.2a, R.sup.4 and R.sup.7 are hydrogen, R.sup.3
is cyclopropyl and R.sup.5 and R.sup.6 are methyl, A cannot be
--NHC(O)H. The explicit provisos exclude oxymorphone and
naltrexone-3-sulfonamides, which were disclosed as having no
activity in vitro or in vivo [McCurdy et al. Org. Lett. 2, 819-821
(2000)]; and cyclazocine formamide, which was disclosed as an
intermediate in a synthesis in U.S. Pat. Nos. 3,957,793; 4,032,529
and 4,205,171. Additionally, when A is --CN, R.sup.7 must be
hydroxyl. When R.sup.4, R.sup.5, R.sup.6, and R.sup.7 form one to
three rings, it is preferred that none of the rings formed by
R.sup.4, R.sup.5, R.sup.6, and R.sup.7 is aryl or heteroaryl.
[0023] Subclasses of the foregoing structure include: [0024] II.
2,6-methano-3-benzazocines of the structure shown above, in which
R.sup.4, R.sup.5, R.sup.6 and R.sup.7 do not form additional rings;
[0025] III. morphinans in which R.sup.5 and R.sup.6 form one
ring:
[0025] ##STR00006## [0026] IV. morphinans in which R.sup.5, R.sup.6
and R.sup.7 form two rings:
##STR00007##
[0026] and [0027] V. morphinans wherein R.sup.4 and R.sup.11 form
an additional sixth ring, which may be saturated or unsaturated
(but not fully aromatic):
##STR00008##
[0028] In addition to the major subclasses, there are compounds
such as
##STR00009##
which the person of skill recognizes as closely related to the
major subclasses, but which defy easy description in a common
Markush structure.
[0029] In another aspect, the invention relates to a method for
preparing a second compound that interacts with an opioid receptor
when a first compound that interacts with an opioid receptor is
known. When the first compound contains a phenolic hydroxyl, the
method comprises converting the phenolic hydroxyl to a residue
chosen from the group described as the variable A above.
[0030] In another aspect, the invention relates to a method for
decreasing the rate of metabolism of a compound that interacts at
an opioid receptor. When the first compound contains a phenolic
hydroxyl, the method comprises converting the phenolic hydroxyl to
a residue chosen from the group described as the variable A
above.
[0031] In another aspect, the invention relates to methods for
inhibiting, eliciting or enhancing responses mediated by an opioid
receptor comprising: [0032] (a) providing a first compound that
inhibits, elicits or enhances an opioid receptor response; [0033]
(b) preparing a second compound that interacts with an opioid
receptor by converting a phenolic hydroxyl group on the first
compound to a residue described as A above; and [0034] (c) bringing
the second compound into contact with the opioid receptor.
[0035] In another aspect, the invention relates to a method for
treating a disease by altering a response mediated by an opioid
receptor. The method comprises bringing into contact with the
opioid receptor a compound having the formula
##STR00010##
wherein B represents the appropriate residue of a known compound of
formula
##STR00011##
and the known compound of that formula alters a response mediated
by an opioid receptor.
[0036] In another aspect, the invention relates to processes for
converting opioid-binding phenols or phenols on a benzomorphan or
morphinan to a carboxamide. The carboxamide conversion processes
comprise either: [0037] (a) reacting the phenol with a reagent to
convert it to a group displaceable by CN.sup.0 ; [0038] (b)
reacting that group with Zn(CN).sub.2 in the presence of a Pd(0)
catalyst to provide a nitrile; and [0039] (c) hydrolyzing the
nitrile to a carboxamide; or: [0040] (a) reacting the phenol with a
reagent to convert the phenol to a triflate; [0041] (b) reacting
the triflate with carbon monoxide and ammonia in the presence of a
Pd(II) salt and a Pd(0) catalyst to provide a carboxamide; or
[0042] (a) reacting the phenol with a reagent to convert the phenol
to a triflate; [0043] (b) reacting the triflate with carbon
monoxide and hexamethyldisilazane in the presence of a Pd(II) salt
and a Pd(0) catalyst to provide a silylated carboxamide precursor;
and [0044] (c) hydrolyzing the silylated carboxamide precursor to
provide a carboxamide.
[0045] Similar processes convert phenols to amidines and thioamides
by reacting the foregoing nitrile with hydroxylamine to produce a
hydroxyamidine or reacting the foregoing carboxamide with a
pentavalent phosphorus-sulfur reagent to produce a thioamide. For
the purpose of the invention an "opioid-binding phenol" is one that
exhibits binding at an opioid receptor below 25 nM.
DETAILED DESCRIPTION OF THE INVENTION
[0046] From many years of SAR studies, it is known that the
hydroxyl of morphinans and benzomorphans interacts with a specific
site in the opiate receptor. Previous exploration of the tolerance
of this site for functional groups other than phenolic hydroxyls
has almost uniformly resulted in the complete or near-complete loss
of opioid binding. We have now surprisingly found that the hydroxyl
can be replaced with one of several bioisosteres. Although a fairly
wide range of primary and secondary carboxamides, as well as
carboxylates, aminomethyl, hydroxymethyl and even dihydroimidazolyl
exhibit binding in the desired range below 25 nanomolar, optimal
activity is observed with a carboxamido, thiocarboxamido,
hydroxyamidino or formamido group.
[0047] Since the hydroxyl functionality of benzomorphans and
morphinans can be chemically converted to an amide by a simple,
flexible and convenient route described below, and since
thiocarboxamido, hydroxyamidino and formamido compounds are also
easily synthesized as described below, the door is opened to
improving the bioavailability of virtually any of the known and new
therapeutic agents that rely on opioid binding for their activity.
Moreover, since the receptor seems to tolerate some variation
beyond the a-carbon of A, one may contemplate further modulating
receptor specificity, affinity and tissue distribution by varying
the properties of the alkyl or aryl substituents on A. Preferred
residues A are --COOCH.sub.3, --COOEt, --CONH.sub.2,
--C(.dbd.S)NH.sub.2, --C(O)NHOH, --C(O)NHNH.sub.2, --CONHCH.sub.3,
--CONHBn, --CONHCH.sub.2(4-MeOC.sub.6H.sub.4),
2-(4,5-dihydroimidazolyl), --C(.dbd.NOH)NH.sub.2,
--CH.sub.2NH.sub.2, CH.sub.2OH, --COC.sub.6H.sub.5,
--C(.dbd.NOH)C.sub.6H.sub.5, --NHCHO, --NHCHS and
--NHSO.sub.2CH.sub.3. When R.sup.7 is hydroxyl, A may also be --CN.
Most preferred are --CONH.sub.2, --C(.dbd.S)NH.sub.2,
--C(.dbd.NOH)NH.sub.2, and --NHCHO.
[0048] It is known in the art that compounds that are .mu., .delta.
and .kappa. agonists exhibit analgesic activity; compounds that are
selective .mu. agonists exhibit anti-diarrheal activity and are
useful in treating dyskinesia; .mu. antagonists and .kappa.
agonists are useful in treating heroin, cocaine, alcohol and
nicotine addiction; .kappa. agonists are also anti-pruritic agents
and are useful in treating hyperalgesia. Recently it has been found
[Peterson et al. Biochem. Pharmacol. 61, 1141-1151 (2001)] that
.kappa. agonists are also useful in treating retroviral infections.
In general, the dextrorotatory isomers of morphinans of type III
above are useful as antitussives and anticonvulsants. Additional
diseases and conditions for which opioid agonists and antagonists
are known to be useful include irritable bowel syndrome,
gastrointestinal motility disorder, obesity and respiratory
depression. Certain opioids (e.g. fentanyl and derivatives) are
useful as anesthetics, i.e., they alter the state of
consciousness.
[0049] Opioid receptor ligands having known high affinity are shown
in the following charts 1 and 2. Replacement of OH in these
compounds produces compounds that exhibit similar activity and
better bioavailability.
##STR00012## ##STR00013##
##STR00014## ##STR00015## ##STR00016##
##STR00017## ##STR00018## ##STR00019##
Other opioid receptor ligands are described in Aldrich, J.V.
"Analgesics" in Burger's Medicinal Chemistry and Drug Discovery, M.
E.Wolff ed., John Wiley & Sons 1996, pages 321-44, the
disclosures of which are incorporated herein by reference.
[0050] We have examined the opioid receptor binding of a series of
analogs of known compounds that interact at opioid receptors in
which the OH is replaced by the R-group shown in Tables 1-4. The
standards are shown in Table 5. The affinities of the compounds of
the invention were determined in guinea pig brain cells by the
method described in Wentland et al. Biorgan. Med. Chem. Lett. 9.
183-187 (2000). Alternatively, where noted, the affinities of the
compounds of the invention were determined in cloned human
receptors in Chinese hamster ovary cells by the method described by
Xu et al [Synapse 39, 64-69 (2001)]. CHO cell membranes, expressing
the human .mu., .delta., or .kappa. opioid receptor, were incubated
with 12 different concentrations of the compounds in the presence
of receptor-specific radioligands at 25.degree. C., in a final
volume of 1 ml of 50 mM Tris-HCl, pH 7.5. Nonspecific binding was
determined using 1 .mu.M naloxone. Data are the mean
value.+-.S.E.M. from three experiments, performed in
triplicate.
TABLE-US-00001 TABLE 1 Cyclazocine subseries ##STR00020## [.sup.3H]
[.sup.3H] [.sup.3H] DAMGO Naltrindole U69,593 example A = (.mu.)
(.delta.) (.kappa.) 1 CN 540 .+-. 50 2700 .+-. 1400 71 .+-. 13 2
COOH 58 .+-. 1.8 320 .+-. 14 31 .+-. 0.87 3 CO.sub.2CH.sub.3 45
.+-. 0.92 59 .+-. 2.1 2.0 .+-. 0.21 4 CONH.sub.2 0.41 .+-. 0.07 8.3
.+-. 0.49 0.53 .+-. 0.06 4 CONH.sub.2 0.32 .+-. 0.04 NT 0.60 .+-.
0.04 4 CONH.sub.2.cndot.HCl 0.34 .+-. 0.01 4.9 .+-. 0.80 0.42 .+-.
0.02 .sup. 4a (-)CONH.sub.2 0.17 .+-. 0.04 2.6 .+-. 0.6 0.28 .+-.
0.01 4b (+)CONH.sub.2 63 .+-. 5.4 570 .+-. 50 67 .+-. 1.6 5
C(.dbd.S)NH.sub.2 0.22 .+-. 0.02 4.0 .+-. 0.48 0.67 .+-. 0.01 6
CONHOH 12 .+-. 0.32 210 .+-. 40 6.9 .+-. 0.61 7 CONHNH.sub.2 60
.+-. 9.3 450 .+-. .A-inverted. 62 19 .+-. 1.4 8 CONHCH.sub.3 24
.+-. 1.6 63 .+-. 4.1 2.6 .+-. 0.19 9 CONHCH.sub.2C.sub.6H.sub.5 20
.+-. 2.2 140 .+-. 18 78 .+-. 7.6 10
CONHCH.sub.2(4-MeOC.sub.6H.sub.4) 19 .+-. 1.5 150 .+-. 17 110 .+-.
3.1.sub. 11 CONHCH.sub.2CH.sub.2N(CH.sub.3).sub.2 26 .+-. 2.9 350
.+-. 51 44 .+-. 11 12 CONH(CH.sub.2).sub.3N(CH.sub.3).sub.2 370
.+-. 54 3000 .+-. 230 310 .+-. 64 13 2-(4,5-H.sub.2)-imidazolyl 23
.+-. 1.9 55 .+-. 5.1 11 .+-. 0.69 14 C(.dbd.NOH)NH.sub.2 3.8 .+-.
0.42 16 .+-. 0.67 0.90 .+-. 0.15 15 CH.sub.2NH.sub.2 31 .+-. 5.4
390 .+-. 47 17 .+-. 2.9 16 CH.sub.2OH 21 .+-. 2.0 210 .+-. 29 7.6
.+-. 0.80 17 COC.sub.6H.sub.5 33 .+-. 0.90 490 .+-. 43 19 .+-. 2.6
18 C(.dbd.NOH)C.sub.6H.sub.5 86 .+-. 3.8 180 .+-. 15 7.2 .+-. 0.40
38 CH.sub.2CN .sup. 3.3 .+-. 1.5 .sup.a .sup. 2000 .+-. 685 .sup.a
.sub. 2.9 .+-. 0.36 .sup.a 39 CH(N.dbd.OH) .sup. 18 .+-. 1.8 .sup.a
.sup. 140 .+-. 15 .sup.a .sup. 0.73 .+-. 0.03 .sup.a 19 NHCHO 1.9
.+-. 0.14 37 .+-. 3.9 0.85 .+-. 0.080 .sup. 19a (-)NHCHO 1.1 .+-.
0.04 9.8 .+-. 0.28 0.49 .+-. 0.012 19b (+)NHCHO 2300 .+-. 180
>10,000 900 .+-. 8.7 20 NHCHS 0.76 .+-. 0.09 16 .+-. 0.30 0.63
.+-. 0.15 21 NHSO.sub.2CH.sub.3 15 .+-. 1.2 780 .+-. 170 21 .+-.
1.5 36 NHCONH.sub.2 20 .+-. 0.66 90 .+-. 12 15 .+-. 1.4 37
NHCSNH.sub.2 .sup. 10 .+-. 1.7 .sup.a .sup. 440 .+-. 72 .sup.a
.sup. 4.0 .+-. 0.54 .sup.a .sup.a data from chinese hamster ovary
rather than guinea pig brain
TABLE-US-00002 TABLE 2 Keto subseries: ##STR00021## [.sup.3H]DAMGO
[.sup.3H]Naltrindole [.sup.3H]U69,593 example A = (.mu.) (.delta.)
(.kappa.) 22 CN (KC) 680 .+-. 61 3400 .+-. 410 59 .+-. 0.77 23
CONH.sub.2 (KC) 1.4 .+-. 0.07 20 .+-. 2.3 1.8 .+-. 0.10 24
CONH.sub.2(EKC) 1.2 .+-. 0.12 9.8 .+-. 0.50 0.70 .+-. 0.08 40 NHCHO
(EKC) 6.1 .+-. 0.83 52 .+-. 3.4 1.2 .+-. 0.11
TABLE-US-00003 TABLE 3 Merz subseries ##STR00022## ex-
[.sup.3H]DAMGO [.sup.3H]Naltrindole [.sup.3H]U69,593 ample A =
(.mu.) (.delta.) (.kappa.) 25 (-)-(2''S)-8-OH 0.19 .+-. 0.01 3.6
.+-. 0.40 0.09 .+-. 0.01 26 (-)-(2''S)-8- 0.052 .+-. 0.013 2.0 .+-.
0.15 0.089 .+-. 0.004 CONH.sub.2 27 (-)-(2''R)-8-OH 4.0 .+-. 0.54
67 .+-. 4.3 1.5 .+-. 0.07 28 (-)-(2''R)-8- 2.9 .+-. 0.17 34 .+-.
0.10 2.8 .+-. 0.24 CONH.sub.2 29 (-)-(2''S)-8- 28 .+-. 2.3 300 .+-.
27 18 .+-. 1.9 CH.sub.2NH.sub.2
TABLE-US-00004 TABLE 4 Other Series ##STR00023## ##STR00024##
##STR00025## ##STR00026## ##STR00027## ##STR00028## ##STR00029##
[.sup.3H]Naltrindole [3.sup.3H]U69,593 example A = [.sup.3H]DAMGO
(.mu.) (.delta.) (.kappa.) 30 CONH.sub.2 (morphine) 34 .+-. 1.8
1900 .+-. 81 2000 .+-. 97 31 CONHCH.sub.3 (morphine) 440 .+-. 9.2
>10,000 >10,000 32 CONH.sub.2 (naltrexone) 1.9 .+-. 0.21 110
.+-. 8.1 22 .+-. 0.85 33 CO.sub.2Et (naltrexone) 24 .+-. 1.7 970
.+-. 155 16 .+-. 0.70 41 (-) NHCHO (naltrexone) .sup. 4.1 .+-. 0.40
.sup.a 280 .+-. 7.6 .sup.a .sup. 2.3 .+-. 0.044 .sup.a 34
CONH.sub.2 (naltrindole) 47 .+-. 2.7 0.33 .+-. 0.04 99 .+-. 7.9 35
CONH.sub.2 (buprenorphine) 2.3 .+-. 0.29 7.3 .+-. 0.61 4.3 .+-.
0.05 42 CONH.sub.2 (nalbuphine) .sup. 3.8 .+-. 0.62 .sup.a .sup.
150 .+-. 82 .sup.a .sup. 0.46 .+-. 0.04 .sup.a 43 CN (7-OH) .sup.
0.35 .+-. 0.092 .sup.a .sup. 82 .+-. 24 .sup.a .sup. 2.6 .+-. 0.21
.sup.a 44 CONH.sub.2 (butorphanol) .sup. 0.15 .+-. 0.019 .sup.a
.sup. 14 .+-. 2.1 .sup.a .sup. 0.39 .+-. 0.057 .sup.a
TABLE-US-00005 TABLE 5 Standards [.sup.3H]Naltrindole
[.sup.3H]U69,593 [.sup.3H]DAMGO (.mu.) (.delta.) (.kappa.)
(.+-.)-Cyclazocine 0.32 .+-. 0.02 1.1 .+-. 0.04 0.18 .+-. 0.020
(.+-.)-Cyclazocine 0.16 .+-. 0.01.sup.a 2.0 .+-. 0.22.sup.a 0.07
.+-. 0.01.sup.a (+)-Cyclazocine 360 .+-. 16 1100 .+-. 63 76 .+-.
8.2 (-)-Cyclazocine 0.10 .+-. 0.03 0.58 .+-. 0.06 0.052 .+-. 0.009
(.+-.)-EKC 0.78 .+-. 0.10 3.4 .+-. 0.41 0.62 .+-. 0.11
(.+-.)-ketocyclazocine 3.3 .+-. 0.66 20 .+-. 2.7 1.0 .+-. 0.24
(.+-.)-ketocyclazocine 1.7 .+-. 0.21.sup.a 130 .+-. 14.sup.a 1.0
.+-. 0.019.sup.a naltrexone (3-OH) 0.17 .+-. 0.03 11 .+-. 1.1 0.31
.+-. 0.03 naltrindole (3-OH) 13 .+-. 1.1 0.13 .+-. 0.02 4.6 .+-.
0.23 buprenorphine 0.98 .+-. 0.11 0.72 .+-. 0.10 0.90 .+-. 0.11
nalbuphine 1.6 .+-. 0.37.sup.a 580 .+-. 80.sup.a 3.0 .+-.
0.63.sup.a butorphanol 0.12 .+-. 0.058.sup.a 12 .+-. 3.8.sup.a 0.22
.+-. 0.023.sup.a
Example 4 was tested several times independently to confirm the
K.sub.i's. Inspection of the results in Table 1 indicates not only
that affinity is preserved in the compounds of the invention, but
also that receptor selectivity can be modulated.
[0051] Antinociceptive activity is evaluated by the method
described in Jiang et al. [J. Pharmacol. Exp. Ther. 264, 1021-1027
(1993), page 1022]. Compound 4 was found to exhibit an ED.sub.50 of
0.21 nmol in the mouse acetic acid writhing test when administered
i.c.v. Its "parent" cyclazocine exhibited an ED.sub.50 of 2.9 nmol
i.c.v. The time courses in producing antinociception in the mouse
writhing test were compared for compound 4 and cyclazocine. Mice
were injected with 1.0 mg/kg of either compound 4 or cyclazocine,
given by i.p. administration. An increase in the duration of action
from ca. 2 hr to 15 hr was observed for compound 4 compared to
cyclazocine.
Definitions
[0052] Throughout this specification the terms and substituents
retain their definitions.
[0053] Alkyl is intended to include linear, branched, or cyclic
hydrocarbon structures and combinations thereof. Lower alkyl refers
to alkyl groups of from 1 to 6 carbon atoms. Examples of lower
alkyl groups include methyl, ethyl, propyl, isopropyl, cyclopropyl,
butyl, s-and t-butyl, cyclobutyl and the like. Preferred alkyl
groups are those of C.sub.20 or below. Cycloalkyl is a subset of
alkyl and includes cyclic hydrocarbon groups of from 3 to 8 carbon
atoms. Examples of cycloalkyl groups include c-propyl, c-butyl,
c-pentyl, norbornyl and the like.
[0054] Alkoxy or alkoxyl refers to groups of from 1 to 8 carbon
atoms of a straight, branched, cyclic configuration and
combinations thereof attached to the parent structure through an
oxygen. Examples include methoxy, ethoxy, propoxy, isopropoxy,
cyclopropyloxy, cyclohexyloxy and the like. Lower-alkoxy refers to
groups containing one to four carbons.
[0055] Aryl and heteroaryl mean a 5- or 6-membered aromatic or
heteroaromatic ring containing 0-3 heteroatoms selected from O, N,
or S; a bicyclic 9- or 10-membered aromatic or heteroaromatic ring
system containing 0-3 heteroatoms selected from O, N, or S; or a
tricyclic 13- or 14-membered aromatic or heteroaromatic ring system
containing 0-3 heteroatoms selected from O, N, or S. Heteroaryl
refers to any maximally unsaturated heterocycle. The aromatic 6- to
14-membered carbocyclic rings include, e.g., benzene, naphthalene,
indane, tetralin, and fluorene and the 5- to 10-membered aromatic
heterocyclic rings include, e.g., pyrrole, imidazole, pyridine,
indole, thiophene, benzopyranone, thiazole, furan, benzimidazole,
quinoline, isoquinoline, quinoxaline, pyrimidine, pyrazine,
tetrazole and pyrazole.
[0056] Arylalkyl means an alkyl residue attached to an aryl ring.
Examples are benzyl, phenethyl and the like. Heteroarylalkyl means
an alkyl residue attached to a heteroaryl ring. Examples include,
e.g., pyridinylmethyl, pyrimidinylethyl and the like.
[0057] Heterocycle means a cycloalkyl or aryl residue in which one
to two of the carbons is replaced by a heteroatom such as oxygen,
nitrogen or sulfur. Heteroaryls form a subset of heterocycles.
Examples of heterocycles that fall within the scope of the
invention include pyrrolidine, pyrazole, pyrrole, indole,
quinoline, isoquinoline, tetrahydroisoquinoline, benzofuran,
benzodioxan, benzodioxole (commonly referred to as
methylenedioxyphenyl, when occurring as a substituent), tetrazole,
morpholine, thiazole, pyridine, pyridazine, pyrimidine, thiophene,
furan, oxazole, oxazoline, isoxazole, dioxane, tetrahydrofuran and
the like.
[0058] Substituted alkyl, aryl, cycloalkyl, or heterocyclyl refer
to alkyl, aryl, cycloalkyl, or heterocyclyl wherein up to three H
atoms in each residue are replaced with halogen, hydroxy,
loweralkoxy, carboxy, carboalkoxy, carboxamido, cyano, carbonyl,
--NO.sub.2, --NR.sup.1R.sup.2; alkylthio, sulfoxide, sulfone,
acylamino, amidino, phenyl, benzyl, heteroaryl, phenoxy, benzyloxy,
heteroaryloxy, or substituted phenyl, benzyl, heteroaryl, phenoxy,
benzyloxy, or heteroaryloxy.
[0059] Virtually all of the compounds described herein contain one
or more asymmetric centers and may thus give rise to enantiomers,
diastereomers, and other stereoisomeric forms that may be defined,
in terms of absolute stereochemistry, as (R)- or (S)-. The present
invention is meant to include all such possible isomers, as well as
their racemic and optically pure forms. In general it has been
found that the levo isomer of morphinans and benzomorphans is the
more potent antinociceptive agent, while the dextro isomer may be
useful as an antitussive or antispasmodic agent. Optically active
(R)- and (S)-isomers may be prepared using chiral synthons or
chiral reagents, or resolved using conventional techniques. When
the compounds described herein contain olefinic double bonds or
other centers of geometric asymmetry, and unless specified
otherwise, it is intended that the compounds include both E and Z
geometric isomers. Likewise, all tautomeric forms are also intended
to be included.
Abbreviations
[0060] The following abbreviations and terms have the indicated
meanings throughout: [0061] Ac=acetyl [0062]
BNB=4-bromomethyl-3-nitrobenzoic acid [0063] Boc=t-butyloxy
carbonyl [0064] Bu=butyl [0065] c--=cyclo [0066]
DAMGO=Tyr-ala-Gly-NMePhe-NHCH.sub.2OH [0067]
DBU=diazabicyclo[5.4.0]undec-7-ene [0068]
DCM=dichloromethane=methylene chloride=CH.sub.2Cl.sub.2 [0069]
DEAD=diethyl azodicarboxylate [0070] DIC=diisopropylcarbodiimide
[0071] DIEA=N,N-diisopropylethyl amine [0072]
DMAP=4-N,N-dimethylaminopyridine [0073] DMF=N,N-dimethylformamide
[0074] DMSO=dimethyl sulfoxide [0075]
DPPF=1,1'-bis(diphenylphosphino)ferrocene [0076]
DVB=1,4-divinylbenzene [0077]
EEDQ=2-ethoxy-l-ethoxycarbonyl-1,2-dihydroquinoline [0078]
Fmoc=9-fluorenylmethoxycarbonyl [0079] GC=gas chromatography [0080]
HATU=O-(7-Azabenzotriazol-1-yl)-1,1,3,3-tetramethyluronium
hexafluorophosphate [0081] HOAc=acetic acid [0082]
HOBt=hydroxybenzotriazole [0083] Me=methyl [0084]
mesyl=methanesulfonyl [0085] MTBE=methyl t-butyl ether [0086]
NMO=N-methylmorpholine oxide [0087] PEG=polyethylene glycol [0088]
Ph=phenyl [0089] PhOH=phenol [0090] PfP=pentafluorophenol [0091]
PPTS=pyridinium p-toluenesulfonate [0092]
PyBroP=bromo-tris-pyrrolidino-phosphonium hexafluorophosphate
[0093] rt=room temperature [0094] sat'd=saturated [0095]
s--=secondary [0096] t--=tertiary [0097] TBDMS=t-butyldimethylsilyl
[0098] TFA=trifluoroacetic acid [0099] THF=tetrahydrofuran [0100]
TMOF=trimethyl orthoformate [0101] TMS=trimethylsilyl [0102]
tosyl=p-toluenesulfonyl [0103] Trt=triphenylmethyl [0104]
U69,593
##STR00030##
[0105] In the general processes described below, the preferred
reagent to convert a phenol to a group displaceable by CN.sup.Y is
trifluoromethansulfonic anhydride, which is usually employed in the
presence of base. Other reagents are known to persons of skill in
the art to convert phenols to groups that may be displaced by
cyanide anion. The advantage of the trifluoromethansulfonic
anhydride procedure is that it allows displacement under conditions
that are mild enough to avoid destruction of the rest of the
molecule for most species of interest. Other reagents are operable,
but require more robust substrates than may be of interest in a
particular case. The consideration of which to use is within the
skill of the artisan. A preferred Pd(0) catalyst for use in the
displacement with zinc cyanide is
tetrakis(triphenylphosphine)palladium. In the direct displacements
with carbon monoxide and ammonia or an ammonia equivalent, the
preferred Pd(0) catalyst is generated in situ from Pd(OAc).sub.2 or
PdCl.sub.2 and 1,1'-bis(diphenylphosphino)ferrocene. Other Pd(0)
ligands include DPPF, DPPP, triphenylphosphine,
1,3-bis(diphenylphosphino)propane, BINAP and xantphos. The
preferred pentavalent phosphorus-sulfur reagents for converting
carboxamides to thiocarboxamides are Lawesson's reagent and
phosphorus pentasulfide.
[0106] It may happen that residues in the substrate of interest
require protection and deprotection during the conversion of the
phenol to the desired bioisostere. Terminology related to
"protecting", "deprotecting" and "protected" functionalities occurs
throughout this application. Such terminology is well understood by
persons of skill in the art and is used in the context of processes
which involve sequential treatment with a series of reagents. In
that context, a protecting group refers to a group which is used to
mask a functionality during a process step in which it would
otherwise react, but in which reaction is undesirable. The
protecting group prevents reaction at that step, but may be
subsequently removed to expose the original functionality. The
removal or "deprotection" occurs after the completion of the
reaction or reactions in which the functionality would interfere.
Thus, when a sequence of reagents is specified, as it is in the
processes of the invention, the person of ordinary skill can
readily envision those groups that would be suitable as "protecting
groups". Suitable groups for that purpose are discussed in standard
textbooks in the field of chemistry, such as Protective Groups in
Organic Synthesis by T. W. Greene [John Wiley & Sons, New York,
1991], which is incorporated herein by reference.
[0107] The compounds of the invention are synthesized by one of the
routes described below:
##STR00031##
##STR00032##
##STR00033##
Chemical Syntheses
[0108] Proton NMR [Varian Unity-500 (500 MHz) NMR] data, direct
insertion probe (DIP) chemical ionization mass spectra (Shimadzu
GC-17A GC-MS mass spectrometer), and infrared spectra (Perkin-Elmer
Paragon 1000 FT-IR spectrophotometer) were consistent with the
assigned structures of all test compounds and intermediates.
.sup.1H NMR multiplicity data are denoted by s (singlet), d
(doublet), t (triplet), q (quartet), m (multiplet), and br (broad).
Coupling constants are in hertz. Carbon, hydrogen, and nitrogen
elemental analyses for all novel targets were performed by
Quantitative Technologies Inc., Whitehouse, N.J., and were within 6
0.4% of theoretical values except as noted; the presence of water
was conformed by proton NMR. Melting points were determined on a
Meltemp capillary melting point apparatus and are uncorrected.
Optical rotation data were obtained from a Perkin-Elmer 241
polarimeter. Reactions were generally performed under a N.sub.2
atmosphere. Amines used in the Pd-catalyzed amination reactions and
racemic-2,2'-bis(diphenylphosphino)-1,1'-binapthyl (BINAP) were
purchased from Aldrich Chemical Company and used as received unless
otherwise indicated. Tris(dibenzylideneacetone) dipalladium (0)
[Pd.sub.2(dba).sub.3], Pd(OAc).sub.2,
1,1'-bis(diphenylphosphino)ferrocene (DPPF), were purchased from
Strem Chemicals, Incorporated. Toluene and Et.sub.2O were distilled
from sodium metal. THF was distilled from sodium/benzophenone
ketyl. Pyridine was distilled from KOH. Methylene chloride was
distilled from CaH.sub.2. DMF and DMSO were distilled from
CaH.sub.2 under reduced pressure. Methanol was dried over
3.+-.molecular sieves prior to use. Silica gel (Bodman Industries,
ICN SiliTech 2-63 D 60A, 230-400 Mesh) was used for flash column
chromatography.
[0109]
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethy-
l-2,6-methano-3-benzazocin-8-carbonitrile [1]. The triflate [36]of
cyclazocine [35] (470 mg, 1.166 mmol), obtained by the method of
Wentland et al.[Bioorgan. Med. Chem. Lett. 9,183-187 (2000)], was
dissolved in 20 mL DMF and Zn(CN).sub.2 (272.6 mg, 2.322 mmol) and
Pd(PPh.sub.3).sub.4 (53.9 mg, 0.0466 mmol) were added. After
heating in 120.degree. C. for 2 h, the reaction was allowed to stir
at 25.degree. C. overnight. A mixture of EtOAc and NaHCO.sub.3
solution was then added. The organic phase was washed with brine
and then dried over anhydrous Na.sub.2SO.sub.4, filtered and
concentrated in vacuo to dryness. Flash column chromatography gave
1 as a colorless oil (260 mg, 80%). .sup.1H-NMR (500 MHz,
CDCl.sub.3) d 7.52 (b,1H), 7.37 (dd, J=7.8, 1.5 Hz, 1H), 7.14 (d,
J=8.1, 1H), 3.15 (m, 1H), 2.96 (d, J=19.0 Hz, 1H), 2.66-2.74 (m,
2H), 2.45 (m, 1H), 2.30 (m, 1H), 1.84-1.98 (m, 3H), 1.38 (s, 3H),
1.29 (m, 1H), 0.85 (m, 1H), 0.82 (d, J=7.1 Hz, 3H), 0.51 (m, 2H),
0.10 (m, 2H). IR (film) 2961, 2918, 2225 cm.sup.-1. CI-MS, m/z
(relative intensity) 281 (M+1, 100%). Anal. Calcd. for
C.sub.19H.sub.24N.sub.2.0.125H.sub.2O: C 80.78, H 8.59, N 9.92.
Found: C 80.75, H 8.63, N 9.89.
[0110]
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethy-
l-2,6-methano-3-benzazocin-8-carboxamide [4]. Compound 1 (80 mg,
0.286 mmol) was dissolved in about 1 mL t-butyl alcohol. KOH (58.8
mg, 1.05 mmol) was then added. The reaction mixture was stirred at
reflux for about 20 min and the solvent was evaporated and
CH.sub.2Cl.sub.2 and MeOH and NaCl solution were added. The organic
phase was washed with brine and then dried over anhydrous
Na.sub.2SO.sub.4, filtered and concentrated in vacuo to dryness to
give 4 as white foam (80 mg, 95%). .sup.1H-NMR (500 MHz,
CD.sub.3OD) d 7.81 (m, 1H), 7.62 (m, 1H), 7.17 (m, 1H), 3.22 (m,
1H), 3.04 (m, 1H), 2.66-2.82 (m, 2H), 2.50 (m, 1H), 2.35 (m, 1H),
1.86-1.98 (m, 3H), 1.34 (s, 3H), 1.36 (m, 1H), 0.88 (m, 1H), 0.84
(d, J=7.0 Hz, 3H), 0.54 (m, 2H), 0.16 (m, 2H) .sup.13C-NMR (500
MHz, CD.sub.3OD) d 172.71, 143.32, 142.34, 133.01, 128.61, 126.61,
126.18, 60.67, 58.09, 46.92, 42.74, 42.38, 37.69, 25.92, 25.07,
14.62, 9.67, 4.64, 4.52. IR (film) 1654.2 cm.sup.-1. CI-MS, m/z
(relative intensity) 299 (M+1, 100%). Anal. Calcd. for
C.sub.19H.sub.26N.sub.2O.0.25H.sub.2O: C 75.37, H 8.76, N 9.26.
Found: C 75.27, H 9.02, N 9.03.
[0111]
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethy-
l-2,6-methano-3-benzazocin-8-carboxamide [1] (alternate procedure).
A flask containing triflate 36 (100 mg), Pd(OAc).sub.2 (10.2 mg),
and 1,1'-bis(diphenylphosphino)ferrocene(DPPF, 25 mg) was purged
with argon. The argon was replaced with gaseous CO and the reaction
vessel was closed to the atmosphere. Dry DMSO (1.25 mL) was added
via syringe and gaseous ammonia was added to the resulting mixture
via a canula. A balloon was used to keep the additional volume
contained. The mixture was stirred for 17 h at 70.degree. C.
followed by cooling to 25.degree. C. The reaction mixture was
diluted with water and the product was extracted into ethyl
acetate. The organic extracts was washed with aqueous NaHCO.sub.3
and dried (Na.sub.2SO.sub.4). Concentration of the solvent in vacuo
gave 90 mg of a crude product. This material was purified via flash
chromatography (25:1:0.1-CH.sub.2Cl.sub.2:MeOH: conc NH.sub.4OH) to
provide 47 mg (65.3%) of compound 4.
[0112]
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6,-hexahydro-cis-6,11-dimeth-
yl-2,6-methano-3-benzazocin-8-carboxylic acid methyl ester [3]. A
modification of a known procedure (Cacchi, S.; Ciattini, P. G.;
Morera, E.; Ortar, G. Tetrahedron Lett. 1986, 27, 3931-3934) was
used in this preparation. Under an argon atmosphere, triethylamine
(0.30 mL, 2.15 mmol) was added to a mixture of the 8-triflate ester
of cyclazocine [36] (0.403 g, 1.0 mmol), palladium acetate (0.0068
g, 0.03 mmol), 1,1'-bis(diphenylphosphino)ferrocene (0.00166 g,
0.03 mmol) and methanol (1 mL, 22.2 mmol) in DMF (1 mL). The
solution was purged with carbon monoxide for 15 min and stirred
under a CO balloon at 70.degree. C. for 5 h. The reaction mixture
was taken up in 20 mL of ethyl acetate and washed with saturated
sodium bicarbonate solution and water. The organic phase was dried
with sodium sulfate and evaporated to give crude product as a brown
oil. Chromatography on silica gel using
CH.sub.2Cl.sub.2:MeOH:NH.sub.4OH (conc)/40:1:0.1 provided the
desired compound 3 (0.235 g, 86.6%) as a colorless oil: .sup.1H NMR
(500 MHz, CDCl.sub.3) .delta. 7.93 (d, J=1.7 Hz, 1H), 7.76 (dd,
J.sub.1=1.7 Hz, J.sub.2=7.8 Hz, 1H), 7.12 (d, J=7.8 Hz, 1H), 3.89
(s, 3H), 3.15 (m, 1H), 2.96 (d, J=19.0 Hz, 1H), 2.73 (d, J=6.1 Hz,
1H), 2.70 (m, 1H), 2.46 (dd, J.sub.1=7.3 Hz, J.sub.2=12.4 Hz, 1H),
2.31 (dd, J.sub.1=6.6 Hz, J.sub.2=12.4 Hz, 1H), 1.96 (m, 1H), 1.91
(m, 2H), 1.43 (s, 3H), 1.33 (m, 1H), 0.86 (m, 1H), 0.83 (d, J=7.1
Hz, 3H), 0.51 (d, J=8.1 Hz, 2H), 0.11 (m, 2H); IR (film)
.nu..sub.max 2916, 1720, 1270 cm.sup.-1; MS (CI) m/z 314
(M+H).sup.+; Anal. calc. for C.sub.20H.sub.27NO.sub.2: C, 76.64; H,
8.68; N, 4.47. Found: C, 76.37; H, 8.93; N, 4.38.
[0113]
(.+-.)-[3-(Cyclopropylmethyl)-1,2,3,4,5,6,-hexahydro-cis-6,11-dimet-
hyl-2,6-methano-3-benzazocin-8-yl]-methanol [16]. Under a blanket
of N.sub.2 at 0.degree. C.,
(.+-.)-3-(cyclopropylmethyl)-1,2,3,4,5,6,-hexahydro-cis-6,11-dimethyl-2,6-
-methano-3-benzazocin-8-carboxylic acid methyl ester [3] (0.1062 g,
0.34 mmol), LiAlH.sub.4 powder (0.0258 g, 0.68 mmol) and dry THF
(0.77 mL) were placed in a one-neck round bottom flask equipped
with condenser and stir bar. The ice/water bath was removed and the
reaction was stirred at reflux for 24 h. The mixture was cooled to
25.degree. C. and quenched by adding water dropwise until
effervescence ceased. The mixture was en treated with 10%
H.sub.2SO.sub.4 and stirred at 25.degree. C. for 3 hours. The
mixture then was extracted with diethyl ether (2X) and the organic
layer was dried (Na.sub.2SO.sub.4) and the solvent was removed in
vacuo. The crude product was purified by flash column
chromatography using CH.sub.2Cl.sub.2:MeOH/10:1 as eluent to
provide the desired product [16] (0.0557 g, 57%) as a light yellow
oil: .sup.1H NMR (500 MHz, CDCl.sub.3) 6 7.24 (d, J=17 Hz, 1H),
7.10 (m, 1H), 7.08 (d, J=21.2 Hz, 1H), 4.64 (s, 2H), 3.14 (m, 1H),
2.91 (d, J=18.5 Hz, 1H), 2.68 (m, 2H), 2.47 (m, 1H), 2.31 (m, 1H),
1.92 (m, 6H), 1.34 (m, 3H), 0.84 (d, J=7.1 Hz), 0.50 (m, 2H), 0.11
(m, 2H); Anal. calc. for C.sub.19H.sub.27NO: C, 79.95; H, 9.53; N,
4.91. Found: C, 79.70; H, 9.50; N, 4.68.
[0114]
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-N-hydroxy-cis-6,-
11-dimethyl-2,6-methano-3-benzazocin-8-carboxamidine [14]. A
modification of a known procedure (Jendralla, H.; Seuring, B.;
Herchen, J.; Kulitzscher, B.; Wunner, J. Tetrahedron 1995, 51,
12047-12068) was used in this preparation. A mixture of
(.+-.)-3-(cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethyl-2,6--
methano-3-benzazocin-8-carbonitrile [1] (0.230 g, 0.82 mmol),
hydroxylamine hydrochloride (0.100 g, 1.44 mmol) and triethylamine
(0.30 mL, 2.15 mmol) in 1 mL of absolute ethanol was stirred at
reflux under an argon atmosphere for 5 h. The reaction mixture was
concentrated in vacuo and the residue was taken up in 15 mL of
CH.sub.2Cl.sub.2 and washed with water. The organic phase was dried
(Na.sub.2SO.sub.4) and evaporated to give crude product. Flash
column chromatography using CH.sub.2Cl.sub.2:MeOH:NH.sub.4OH
(conc)/25:1:0.1 provided the desired compound 14 (0.216 g, 84%) as
a white foam: .sup.1H NMR (500 MHz, CDCl.sub.3) .delta. 9.48 (br s,
1H), 7.56 (d, J=1.5 Hz, 1H), 7.33 (dd, J.sub.1=1.5 Hz, J.sub.2=7.8
Hz, 1H), 7.08 (d, J=7.8 Hz, 1H), 4.84 (s, 2H), 3.19 (m, 1H), 2.94
(d, J=18.8 Hz, 1H), 2.72 (m, 2H), 2.48 (dd, J.sub.1=6.3 Hz,
J.sub.2=12.5 Hz, 1H), 2.34 (dd, J.sub.1=6.6 Hz, J.sub.2=12.5 Hz,
1H), 2.01 (m, 3H), 1.42 (s, 3H), 1.34 (d, J=11.4 Hz, 1H), 0.92 (m,
1H), 0.84 (d, J=6.8 Hz, 3H), 0.51 (m, 2H), 0.12 (m, 2H); IR (film)
.nu..sub.max 3365, 2921, 1634, 1577 cm.sup.-1; MS (CI) m/z 314
(M+H).sup.+; Anal. calc. for C.sub.19H.sub.27N.sub.3O: C, 72.81; H,
8.68; N, 13.47. Found: C, 72.96; H, 8.67; N, 13.18.
[0115]
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethy-
l-2,6-methano-3-benzazocin-8-thiocarboxamide [5]. A modification of
a known procedure (Varma R. S.; Kumar, D. Organic Lett. 1999,1,
697-700) was used in this preparation. A mixture of
(.+-.)-3-(cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethyl-2,6--
methano-3-benzazocin-8-carboxamide [4] (0.0298 g, 0.1 mmol) and
Lawsson's reagent (0.0320 g, 0.08 mmol) in 1 mL of toluene was
sealed in a glass tube under an argon atmosphere. The glass tube
was put in a microwave oven and irradiated for 7 min. Additional
Lawsson's reagent (0.0160 g, 0.04 mmol) was added and the reactants
was allowed to be irradiated for additional 7 min. The reaction
mixture was taken up in 10 mL of CH.sub.2Cl.sub.2 and washed with
water. The organic phase was dried with sodium sulfate and
evaporated to give crude product. Chromatography on silica gel
using CH.sub.2Cl.sub.2:MeOH:NH.sub.4OH (conc)/40:1:0.1 the provided
desired compound 5 (0.022 g , 70.1%) as a yellow crystalline solid:
mp 171-173.degree. C.; .sup.1H NMR (500 MHz, CDCl.sub.3) .delta.
7.78 (d, J=1.9 Hz, 1H), 7.64 (brs, 1H), 7.60(dd, J.sub.1=1.9 Hz,
J.sub.2=8.1 Hz, 1H), 7.19 (brs, 1H), 7.09 (d, J=8.1 Hz, 1H), 3.16
(m, 1H), 2.95 (d, J=19.0 Hz, 1H), 2.70 (m, 2H), 2.46 (dd,
J.sub.1=6.1 Hz, J.sub.2=12.4 Hz, 1H), 2.32 (dd, J.sub.1=6.3 Hz,
J.sub.2=12.4 Hz, 1H), 1.92 (m, 3H), 1.43 (s, 3H), 1.34 (m, 1H),
0.85 (m, 1H), 0.83 (d, J=7.1 Hz, 3H), 0.51 (m, 2H), 0.10 (m, 2H);
IR (film) .nu..sub.max 3172, 2920, 1617, 1424 cm.sup.-1; MS (CI)
m/z 315 (M+H).sup.+; Anal. calc. for C.sub.19H.sub.26N.sub.2S.0.75
H.sub.2O: C, 69.58; H, 8.45; N, 8.54. Found: C, 69.54; H, 8.15; N,
8.26.
[0116]
(.+-.)-[3-(Cyclopropylmethyl)-1,2,3,4,5,6,-hexahydro-cis-6,11-dimet-
hyl-2,6-methano-3-benzazocin-8-yl]-methylamine [15].
(.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5,6-hexahydro-cis-6,11-dimethyl-2,6--
methano-3-benzazocin-8-carbonitrile [1] (0.154 g, 0.55 mmol) was
dissolved in Et.sub.2O (1.1 mL) to obtain a 0.5 M solution. This
solution was added dropwise via syringe to a vigorously stirred
solution of 1.0 M LiAlH.sub.4 in Et.sub.2O (1.1 mL, 1.1 mmol) at
0.degree. C. After stirring at room temperature for 10 min, water
was added dropwise to quench the reaction. The resulting solution
was then extracted with EtOAc several times and the combined EtOAc
layers were dried (Na.sub.2SO.sub.4), and filtered. The solvent was
removed in vacuo and the residue purified by flash column
chromatography (CH.sub.2Cl.sub.2:MeOH:Et.sub.3N/10:1:0.2) to yield
the desired product 15 (0.105 g, 67%) as a brown oil: .sup.1H NMR
(500 MHz, CDCl3) .delta. 7.16 (s, 1H), 7.04 (m, 2H), 3.82 (s, 2H),
3.16 (s, 1H), 2.91 (d, J=8.3Hz, 1H), 2.70 (m, 2H), 2.49 (m, 1H),
2.34 (m, 1H), 1.92 (m, 5H), 1.39 (m, 4H), 0.85 (m, 4H), 0.51 (d,
J=7.6 Hz, 2H), 0.11 (m, 2H); IR (film) <.sub.max 3075, 2962,
2917, 2814, 1574, 1499, 1462, 1428, 1380, 1333, 1218, 1101, 1075,
1018, 963 cm.sup.-1; Anal. calc. for
C.sub.19H.sub.28N.sub.20.5H.sub.2O: C, 77.77; H, 9.96; N, 9.54.
Found: C, 78.18; H, 10.17; N, 9.39.
[0117]
(.+-.)-N-[3-(Cyclopropylmethyl)-1,2,3,4,5,6,-hexahydro-cis-6,11-dim-
ethyl-2,6-methano-3-benzazocin-8-yl]-formamide [19]. A modification
of a known procedure (Chakrabarty, M.; Khasnobis, S.; Harigaya, Y.;
Kinda, Y. Synthetic Comm. 2000, 30, 187-200.) was used in this
preparation. (.+-.)-3-(Cyclopropylmethyl)-1,2,3,4,5
,6-hexahydro-cis-6,11-dimethyl-2,6-methano-3-benzazocin-8-amine
[37] (0.091 g, 0.337 mmol) was treated with 96% formic acid (20 mL)
and was heated at 100.degree. C. for 14 h. The solution was then
poured onto crushed ice and basified with solid NaHCO.sub.3. The
organic material was extracted into EtOAc (3.times.) and the
extracts were washed with water and dried (Na.sub.2SO.sub.4). After
concentration in vacuo, the crude product was purified by flash
column chromatography (CH.sub.2Cl.sub.2:MeOH:NH.sub.4OH/10:1:0.05)
to yield the desired product 19 as a brown oil (0.065 g, 65%):
.sup.1H NMR (500 MHz, CDCl.sub.3) .delta. 8.62 (d, J=11.5 Hz, 0.5H,
CHO of one rotomer), 8.34 (d, J=1.7 Hz, 0.5H, CHO of other
rotomer), 8.17 (d, J=10.5 Hz, 0.5H, NH of one rotomer), 7.57 (br s,
0.5H, NH of other rotomer), 7.36 (m, 1H), 7.04 (m, 1H), 6.89 (m,
1H), 3.15 (m, 1H), 2.90 (m, 1H), 2.72 (m, 2H), 2.47 (m, 1H), 2.32
(m, 1H), 1.95 (m, 3H), 1.32 (m, 4H), 0.85 (m, 4H), 0.51 (m, 2H),
0.11 (m, 2H); IR (film) .nu..sub.max 3265, 2963, 2922, 1694, 1682,
1614, 1538, 1503, 1462, 1402, 1380, 1311, 1218, 1100, 1074, 1020,
964, 888, 808 cm.sup.-1; MS (CI) m/z 299 (M+H).sup.+; Anal. calc.
for C.sub.19H.sub.26N.sub.2O.0.125H.sub.2O: C, 75.90; H, 8.88; N,
9.32. Found: C, 76.00; H, 8.95; N, 9.13.
[0118] The remaining compounds of Table 1 were prepared in similar
fashion, except Example 8, which was made by the CO/palladium
route, but with a slight variation using 2.0 M CH.sub.3NH.sub.2 in
THF, rather than gaseous CH.sub.3NH.sub.2, and DMF rather than
DMSO; mp=155-156.degree. C.; 25.6% yield. 24-[the (6)-8-CONH.sub.2
analogue of ethylketocyclazocine (R.sup.2 and R.sup.2a.dbd.O;
R.sup.6=Et)] was made by the nitrile hydrolysis route,
mp=194-196.degree. C.; Step 1-89.1%, Step 2-81.4%. 23-[the
(6)-8-CONH.sub.2 analogue of ketocyclazocine (R.sup.2 and
R.sup.2a.dbd.O; R.sup.6=Me)] was made by the nitrile hydrolysis
route, mp=206-207.degree. C.; Step 1-99.7%, Step 2-94.2%. It was
also made by the CO/Pd route in 34.7% yield.
[0119] In general, the chemistry described above works in the
presence of the variety of functional groups found on known core
structures. The exceptions would be morphine and congeners having a
free 6-OH, which can be protected by a TBDPS (t-butyldiphenylsilyl)
group [see Wentland et al J. Med. Chem. 43, 3558-3565 (2000)].
[0120] The compound identified as Example 43 in table 4 was
prepared by treating the nitrile of nalbuphine with an excess of
potassium hydroxide in t-butanol as described for example 4 above.
Hydrolysis of the nitrile appears to have proceeded more slowly
than elimination and ring opening.
[0121] Although this invention is susceptible to embodiment in many
different forms, preferred embodiments of the invention have been
shown. It should be understood, however, that the present
disclosure is to be considered as an exemplification of the
principles of this invention and is not intended to limit the
invention to the embodiments illustrated. It may be found upon
examination that certain members of the claimed genus are not
patentable to the inventors in this application. In this event,
subsequent exclusions of species from the compass of applicants'
claims are to be considered artifacts of patent prosecution and not
reflective of the inventors' concept or description of their
invention; the invention encompasses all of the members of the
genus (I) that are not already in the possession of the public.
* * * * *