U.S. patent application number 15/252132 was filed with the patent office on 2016-12-22 for nmda receptor modulators and uses thereof.
The applicant listed for this patent is Forest Laboratories Holdings Ltd.. Invention is credited to M. A. Khan, Joseph Moskal.
Application Number | 20160368947 15/252132 |
Document ID | / |
Family ID | 48168770 |
Filed Date | 2016-12-22 |
United States Patent
Application |
20160368947 |
Kind Code |
A1 |
Moskal; Joseph ; et
al. |
December 22, 2016 |
NMDA Receptor Modulators and Uses Thereof
Abstract
Disclosed are compounds having enhanced potency in the
modulation of NMDA receptor activity. Such compounds are
contemplated for use in the treatment of diseases and disorders,
such as learning, cognitive activities, and analgesia, particularly
in alleviating and/or reducing neuropathic pain. Orally available
formulations and other pharmaceutically acceptable delivery forms
of the compounds, including intravenous formulations, are also
disclosed.
Inventors: |
Moskal; Joseph; (Evanston,
IL) ; Khan; M. A.; (Evanston, IL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Forest Laboratories Holdings Ltd. |
Hamilton |
|
BM |
|
|
Family ID: |
48168770 |
Appl. No.: |
15/252132 |
Filed: |
August 30, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14162328 |
Jan 23, 2014 |
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15252132 |
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13525861 |
Jun 18, 2012 |
8673843 |
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14162328 |
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61550782 |
Oct 24, 2011 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61P 25/18 20180101;
A61K 38/07 20130101; A61P 25/24 20180101; A61P 25/22 20180101; A61K
38/00 20130101; A61P 25/14 20180101; C07K 5/0823 20130101; A61P
25/28 20180101; C07K 5/1013 20130101; C07D 403/06 20130101; A61P
25/00 20180101; C07K 5/06165 20130101; A61P 43/00 20180101 |
International
Class: |
C07K 5/103 20060101
C07K005/103 |
Claims
1-12. (canceled)
13. A method of modulating the NMDA receptor comprising the step of
administering a compound represented by: ##STR00020## wherein
R.sup.4 is H; R.sup.1 is benzyl; R.sup.5 is ##STR00021## R.sup.2 is
H or CH.sub.3; R.sup.3 is H or CH.sub.3, and stereoisomers,
N-oxides or pharmaceutically acceptable salts thereof.
14. The method of claim 1, wherein R.sup.2 and R.sup.3 are
CH.sub.3.
15. The method of claim 1, wherein R.sup.2 is CH.sub.3 and R.sup.3
is H.
16. The method of claim 1, wherein the compound is represented by:
##STR00022##
17. A method of modulating the NMDA receptor comprising the step of
administering a compound represented by: ##STR00023##
18. The method of claim 1, wherein said administration is provided
to a patient suffering from at least one of cerebral ischemia,
stroke, brain trauma, brain tumors, acute neuropathic pain, chronic
neuropathic pain, sleep disorders, drug addiction, depression,
certain vision disorders, ethanol withdrawal, anxiety, and memory
and learning disabilities.
19. The method of claim 5, wherein said administration is provided
to a patient suffering from at least one of cerebral ischemia,
stroke, brain trauma, brain tumors, acute neuropathic pain, chronic
neuropathic pain, sleep disorders, drug addiction, depression,
certain vision disorders, ethanol withdrawal, anxiety, and memory
and learning disabilities
Description
RELATED APPLICATIONS
[0001] This application claims priority to U.S. Ser. No.
13/525,861, filed Jun. 18, 2012, which claims priority to U.S.
Provisional Application No. 61/550,782, filed Oct. 24, 2011, and is
a continuation in part of PCT/US11/24583, filed Feb. 11, 2011,
claiming priority to U.S. Provisional Application No. 61/303,472,
filed Feb. 11, 2010; all of which are hereby incorporated by
reference in their entireties.
BACKGROUND
[0002] An N-methyl-d-aspartate (NMDA) receptor is a postsynaptic,
ionotropic receptor that is responsive to, inter alia, the
excitatory amino acids glutamate and glycine and the synthetic
compound NMDA. The NMDA receptor controls the flow of both divalent
and monovalent ions into the postsynaptic neural cell through a
receptor associated channel (Foster et al., Nature 1987,
329:395-396; Mayer et al., Trends in Pharmacol. Sci. 1990,
11:254-260). The NMDA receptor has been implicated during
development in specifying neuronal architecture and synaptic
connectivity, and may be involved in experience-dependent synaptic
modifications. In addition, NMDA receptors are also thought to be
involved in long term potentiation and central nervous system
disorders.
[0003] The NMDA receptor plays a major role in the synaptic
plasticity that underlies many higher cognitive functions, such as
memory acquisition, retention and learning, as well as in certain
cognitive pathways and in the perception of pain (Collingridge et
al., The NMDA Receptor, Oxford University Press, 1994). In
addition, certain properties of NMDA receptors suggest that they
may be involved in the information-processing in the brain that
underlies consciousness itself.
[0004] The NMDA receptor has drawn particular interest since it
appears to be involved in a broad spectrum of CNS disorders. For
instance, during brain ischemia caused by stroke or traumatic
injury, excessive amounts of the excitatory amino acid glutamate
are released from damaged or oxygen deprived neurons. This excess
glutamate binds to the NMDA receptors which opens their
ligand-gated ion channels; in turn the calcium influx produces a
high level of intracellular calcium which activates a biochemical
cascade resulting in protein degradation and cell death. This
phenomenon, known as excitotoxicity, is also thought to be
responsible for the neurological damage associated with other
disorders ranging from hypoglycemia and cardiac arrest to epilepsy.
In addition, there are preliminary reports indicating similar
involvement in the chronic neurodegeneration of Huntington's,
Parkinson's, and Alzheimer's diseases. Activation of the NMDA
receptor has been shown to be responsible for post-stroke
convulsions, and, in certain models of epilepsy, activation of the
NMDA receptor has been shown to be necessary for the generation of
seizures. Neuropsychiatric involvement of the NMDA receptor has
also been recognized since blockage of the NMDA receptor Ca.sup.++
channel by the animal anesthetic PCP (phencyclidine) produces a
psychotic state in humans similar to schizophrenia (reviewed in
Johnson, K. and Jones, S., 1990). Further, NMDA receptors have also
been implicated in certain types of spatial learning.
[0005] The NMDA receptor is believed to consist of several protein
chains embedded in the postsynaptic membrane. The first two types
of subunits discovered so far form a large extracellular region,
which probably contains most of the allosteric binding sites,
several transmembrane regions looped and folded so as to form a
pore or channel, which is permeable to Ca.sup.++, and a carboxyl
terminal region. The opening and closing of the channel is
regulated by the binding of various ligands to domains (allosteric
sites) of the protein residing on the extracellular surface. The
binding of the ligands is thought to affect a conformational change
in the overall structure of the protein which is ultimately
reflected in the channel opening, partially opening, partially
closing, or closing.
[0006] NMDA receptor compounds may exert dual (agonist/antagonist)
effect on the NMDA receptor through the allosteric sites. These
compounds are typically termed "partial agonists". In the presence
of the principal site ligand, a partial agonist will displace some
of the ligand and thus decrease Ca.sup.++ flow through the
receptor. In the absence of or lowered level of the principal site
ligand, the partial agonist acts to increase Ca.sup.++ flow through
the receptor channel.
[0007] A need continues to exist in the art for novel and more
specific/potent compounds that are capable of binding the glycine
binding site of NMDA receptors, and provide pharmaceutical
benefits. In addition, a need continues to exist in the medical
arts for an orally deliverable forms of such compounds.
SUMMARY
[0008] Provided herein, at least in part, are compounds that are
NMDA modulators, for example, partial agonists of NMDA. For
example, disclosed herein are compounds represented by the formula:
A compound represented by:
##STR00001##
wherein: and pharmaceutically acceptable salts, stereoisomers,
metabolites, and hydrates thereof, wherein: R.sup.1, R.sup.2,
R.sup.3, R.sup.4, and X are as defined below.
[0009] Also provided herein are pharmaceutically acceptable
compositions comprising a disclosed compound, and a
pharmaceutically acceptable excipient. For example, such
compositions may be suitable for oral administration to a
patient.
[0010] In another aspect, a method of treating a condition selected
from the group consisting of depression, Alzheimer's disease,
memory loss that accompanies early stage Alzheimer's disease,
attention deficit disorder, ADHD, schizophrenia, anxiety, in a
patient in need thereof is provided. The method comprises
administering to the patient a pharmaceutically effective amount of
a disclosed compound and pharmaceutically acceptable salts,
stereoisomers, metabolites, and hydrates thereof.
DETAILED DESCRIPTION
[0011] This disclosure is generally directed to compounds that are
capable of modulating NMDA, e.g., NMDA antagonists or partial
agonists, and compositions and/or methods of using the disclosed
compounds.
DEFINITIONS
[0012] In some embodiments, the compounds, as described herein, may
be substituted with any number of substituents or functional
moieties. In general, the term "substituted" whether preceded by
the term "optionally" or not, and substituents contained in
formulas, refer to the replacement of hydrogen radicals in a given
structure with the radical of a specified substituent.
[0013] In some instances, when more than one position in any given
structure may be substituted with more than one substituent
selected from a specified group, the substituent may be either the
same or different at every position.
[0014] As used herein, the term "substituted" is contemplated to
include all permissible substituents of organic compounds. In a
broad aspect, the permissible substituents include acyclic and
cyclic, branched and unbranched, carbocyclic and heterocyclic,
aromatic and non-aromatic substituents of organic compounds. In
some embodiments, heteroatoms such as nitrogen may have hydrogen
substituents and/or any permissible substituents of organic
compounds described herein which satisfy the valencies of the
heteroatoms. Non-limiting examples of substituents include acyl;
aliphatic; heteroaliphatic; aryl; heteroaryl; arylalkyl;
heteroarylalkyl; alkoxy; cycloalkoxy; heterocyclylalkoxy;
heterocyclyloxy; heterocyclyloxyalkyl; alkenyloxy; alkynyloxy;
aryloxy; heteroalkoxy; heteroaryloxy; alkylthio; arylthio;
heteroarylthio; oxo; --F; --Cl; --Br; --I; --OH; --NO.sub.2;
--N.sub.3; --CN; --SCN; --SR.sup.x; --CF.sub.3; --CH.sub.2CF.sub.3;
--CHCl.sub.2; --CH.sub.2OH; --CH.sub.2CH.sub.2OH;
--CH.sub.2NH.sub.2; --CH.sub.2SO.sub.2CH.sub.3; --OR.sup.x,
--C(O)R.sup.x; --CO.sub.2(R.sup.x); --C(O)N(R.sup.x).sub.2;
--C(NR.sup.x)N(R.sup.x).sub.2; --OC(O)R.sup.x; --OCO.sub.2R.sup.x;
--OC(O)N(R.sup.x).sub.2; --N(R.sup.x).sub.2; --SOR.sup.x;
--S(O).sub.2R.sup.x; --NR.sup.xC(O)R.sup.x;
--NR.sup.xC(O)N(R.sup.x).sub.2; --NR.sup.xC(O)OR.sup.x;
--NR.sup.xC(NR.sup.x)N(R.sup.x).sub.2; and --C(R.sup.x).sub.3;
wherein each occurrence of R.sup.x independently includes, but is
not limited to, hydrogen, halogen, acyl, aliphatic,
heteroaliphatic, aryl, heteroaryl, arylalkyl, or heteroarylalkyl,
wherein any of the aliphatic, heteroaliphatic, arylalkyl, or
heteroarylalkyl substituents described above and herein may be
substituted or unsubstituted, branched or unbranched, cyclic or
acyclic, and wherein any of the aryl or heteroaryl substituents
described above and herein may be substituted or unsubstituted.
Furthermore, the compounds described herein are not intended to be
limited in any manner by the permissible substituents of organic
compounds. In some embodiments, combinations of substituents and
variables described herein may be preferably those that result in
the formation of stable compounds. The term "stable," as used
herein, refers to compounds which possess stability sufficient to
allow manufacture and which maintain the integrity of the compound
for a sufficient period of time to be detected and preferably for a
sufficient period of time to be useful for the purposes detailed
herein.
[0015] The terms "aryl" and "heteroaryl," as used herein, refer to
mono- or polycyclic unsaturated moieties having preferably 3-14
carbon atoms, each of which may be substituted or unsubstituted. In
certain embodiments, "aryl" refers to a mono- or bicyclic
carbocyclic ring system having one or two aromatic rings including,
but not limited to, phenyl, naphthyl, tetrahydronaphthyl, indanyl,
indenyl, and the like. In certain embodiments, "heteroaryl" refers
to a mono- or bicyclic heterocyclic ring system having one or two
aromatic rings in which one, two, or three ring atoms are
heteroatoms independently selected from the group consisting of S,
O, and N and the remaining ring atoms are carbon. Non-limiting
examples of heteroaryl groups include pyridyl, pyrazinyl,
pyrimidinyl, pyrrolyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl,
isooxazolyl, thiadiazolyl, oxadiazolyl, thiophenyl, furanyl,
quinolinyl, isoquinolinyl, and the like.
[0016] The term "alkyl" as used herein refers to a saturated
straight or branched hydrocarbon, for example, such as a straight
or branched group of 1-6, 1-4, or 1-3 carbon atom, referred to
herein as C.sub.1-C.sub.6alkyl, C.sub.1-C.sub.4alkyl, and
C.sub.1-C.sub.3alkyl, respectively. Exemplary alkyl groups include,
but are not limited to, methyl, ethyl, propyl, isopropyl,
2-methyl-1-propyl, 2-methyl-2-propyl, 2-methyl-1-butyl,
3-methyl-1-butyl, 2-methyl-3-butyl, 2,2-dimethyl-1-propyl,
2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl,
2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl,
2,2-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, butyl,
isobutyl, t-butyl, pentyl, isopentyl, neopentyl, hexyl, heptyl,
octyl, etc.
[0017] Alkyl, alkenyl and alkynyl groups can optionally be
substituted, if not indicated otherwise, with one or more groups
selected from alkoxy, alkyl, cycloalkyl, amino, halogen, and
C(O)alkyl. In certain embodiments, the alkyl, alkenyl, and alkynyl
groups are not substituted, i.e., they are unsubstituted.
[0018] The term "amine" or "amino" as used herein refers to a
radical of the form --NR.sup.dR.sup.e, where R.sup.d and R.sup.e
are independently selected from hydrogen, alkyl, alkenyl, alkynyl,
aryl, arylalkyl, cycloalkyl, haloalkyl, heteroaryl, and
heterocyclyl. The amino also may be cyclic, for example, R.sup.d
and R.sup.e are joined together with the N to form a 3- to
12-membered ring, e.g., morpholino or piperidinyl. The term amino
also includes the corresponding quaternary ammonium salt of any
amino group, e.g., --[N(R.sup.d)(R.sup.e)(R.sup.f)]+. Exemplary
amino groups include aminoalkyl groups, wherein at least one of
R.sup.d, R.sup.e, or R.sup.f is an alkyl group. In certain
embodiment, R.sup.d and R.sup.e are hydrogen or alkyl.
[0019] The terms "halo" or "halogen" or "Hal" as used herein refer
to F, Cl, Br, or I. The term "haloalkyl" as used herein refers to
an alkyl group substituted with one or more halogen atoms.
[0020] The terms "heterocyclyl" or "heterocyclic group" are
art-recognized and refer to saturated or partially unsaturated 3-
to 10-membered ring structures, alternatively 3- to 7-membered
rings, whose ring structures include one to four heteroatoms, such
as nitrogen, oxygen, and sulfur. Heterocycles may also be mono-,
bi-, or other multi-cyclic ring systems. A heterocycle may be fused
to one or more aryl, partially unsaturated, or saturated rings.
Heterocyclyl groups include, for example, biotinyl, chromenyl,
dihydrofuryl, dihydroindolyl, dihydropyranyl, dihydrothienyl,
dithiazolyl, homopiperidinyl, imidazolidinyl, isoquinolyl,
isothiazolidinyl, isoxazolidinyl, morpholinyl, oxolanyl,
oxazolidinyl, phenoxanthenyl, piperazinyl, piperidinyl, pyranyl,
pyrazolidinyl, pyrazolinyl, pyridyl, pyrimidinyl, pyrrolidinyl,
pyrrolidin-2-onyl, pyrrolinyl, tetrahydrofuryl,
tetrahydroisoquinolyl, tetrahydropyranyl, tetrahydroquinolyl,
thiazolidinyl, thiolanyl, thiomorpholinyl, thiopyranyl, xanthenyl,
lactones, lactams such as azetidinones and pyrrolidinones, sultams,
sultones, and the like. The heterocyclic ring may be substituted at
one or more positions with substituents such as alkanoyl, alkoxy,
alkyl, alkenyl, alkynyl, amido, amidino, amino, aryl, arylalkyl,
azido, carbamate, carbonate, carboxy, cyano, cycloalkyl, ester,
ether, formyl, halogen, haloalkyl, heteroaryl, heterocyclyl,
hydroxyl, imino, ketone, nitro, phosphate, phosphonato,
phosphinato, sulfate, sulfide, sulfonamido, sulfonyl and
thiocarbonyl. In certain embodiments, the heterocyclic group is not
substituted, i.e., the heterocyclic group is unsubstituted.
[0021] The terms "hydroxy" and "hydroxyl" as used herein refers to
the radical --OH.
[0022] The term "oxo" as used herein refers to the radical
.dbd.O.
[0023] "Pharmaceutically or pharmacologically acceptable" include
molecular entities and compositions that do not produce an adverse,
allergic or other untoward reaction when administered to an animal,
or a human, as appropriate. "For human administration, preparations
should meet sterility, pyrogenicity, general safety and purity
standards as required by FDA Office of Biologics standards.
[0024] As used in the present disclosure, the term "partial NMDA
receptor agonist" is defined as a compound that is capable of
binding to a glycine binding site of an NMDA receptor; at low
concentrations a NMDA receptor agonist acts substantially as
agonist and at high concentrations it acts substantially as an
antagonist. These concentrations are experimentally determined for
each and every "partial agonist.
[0025] As used herein "pharmaceutically acceptable carrier" or
"excipient" includes any and all solvents, dispersion media,
coatings, antibacterial and antifungal agents, isotonic and
absorption delaying agents, and the like that are physiologically
compatible. In one embodiment, the carrier is suitable for
parenteral administration. Alternatively, the carrier can be
suitable for intravenous, intraperitoneal, intramuscular,
sublingual or oral administration. Pharmaceutically acceptable
carriers include sterile aqueous solutions or dispersions and
sterile powders for the extemporaneous preparation of sterile
injectable solutions or dispersion. The use of such media and
agents for pharmaceutically active substances is well known in the
art. Except insofar as any conventional media or agent is
incompatible with the active compound, use thereof in the
pharmaceutical compositions of the invention is contemplated.
Supplementary active compounds can also be incorporated into the
compositions.
[0026] The term "pharmaceutically acceptable salt(s)" as used
herein refers to salts of acidic or basic groups that may be
present in compounds used in the present compositions. Compounds
included in the present compositions that are basic in nature are
capable of forming a wide variety of salts with various inorganic
and organic acids. The acids that may be used to prepare
pharmaceutically acceptable acid addition salts of such basic
compounds are those that form non-toxic acid addition salts, i.e.,
salts containing pharmacologically acceptable anions, including but
not limited to malate, oxalate, chloride, bromide, iodide, nitrate,
sulfate, bisulfate, phosphate, acid phosphate, isonicotinate,
acetate, lactate, salicylate, citrate, tartrate, oleate, tannate,
pantothenate, bitartrate, ascorbate, succinate, maleate,
gentisinate, fumarate, gluconate, glucaronate, saccharate, formate,
benzoate, glutamate, methanesulfonate, ethanesulfonate,
benzenesulfonate, p-toluenesulfonate and pamoate (i.e.,
1,1'-methylene-bis-(2-hydroxy-3-naphthoate)) salts. Compounds
included in the present compositions that include an amino moiety
may form pharmaceutically acceptable salts with various amino
acids, in addition to the acids mentioned above. Compounds included
in the present compositions that are acidic in nature are capable
of forming base salts with various pharmacologically acceptable
cations. Examples of such salts include alkali metal or alkaline
earth metal salts and, particularly, calcium, magnesium, sodium,
lithium, zinc, potassium, and iron salts.
[0027] The compounds of the disclosure may contain one or more
chiral centers and/or double bonds and, therefore, exist as
stereoisomers, such as geometric isomers, enantiomers or
diastereomers. The term "stereoisomers" when used herein consist of
all geometric isomers, enantiomers or diastereomers. These
compounds may be designated by the symbols "R" or "S," depending on
the configuration of substituents around the stereogenic carbon
atom. The present invention encompasses various stereoisomers of
these compounds and mixtures thereof. Stereoisomers include
enantiomers and diastereomers. Mixtures of enantiomers or
diastereomers may be designated "(.+-.)" in nomenclature, but the
skilled artisan will recognize that a structure may denote a chiral
center implicitly.
[0028] Individual stereoisomers of compounds of the present
invention can be prepared synthetically from commercially available
starting materials that contain asymmetric or stereogenic centers,
or by preparation of racemic mixtures followed by resolution
methods well known to those of ordinary skill in the art. These
methods of resolution are exemplified by (1) attachment of a
mixture of enantiomers to a chiral auxiliary, separation of the
resulting mixture of diastereomers by recrystallization or
chromatography and liberation of the optically pure product from
the auxiliary, (2) salt formation employing an optically active
resolving agent, or (3) direct separation of the mixture of optical
enantiomers on chiral chromatographic columns. Stereoisomeric
mixtures can also be resolved into their component stereoisomers by
well known methods, such as chiral-phase gas chromatography,
chiral-phase high performance liquid chromatography, crystallizing
the compound as a chiral salt complex, or crystallizing the
compound in a chiral solvent. Stereoisomers can also be obtained
from stereomerically-pure intermediates, reagents, and catalysts by
well known asymmetric synthetic methods.
[0029] Geometric isomers can also exist in the compounds of the
present invention. The symbol denotes a bond that may be a single,
double or triple bond as described herein. The present invention
encompasses the various geometric isomers and mixtures thereof
resulting from the arrangement of substituents around a
carbon-carbon double bond or arrangement of substituents around a
carbocyclic ring. Substituents around a carbon-carbon double bond
are designated as being in the "Z" or "E" configuration wherein the
terms "Z" and "E" are used in accordance with IUPAC standards.
Unless otherwise specified, structures depicting double bonds
encompass both the "E" and "Z" isomers.
[0030] Substituents around a carbon-carbon double bond
alternatively can be referred to as "cis" or "trans," where "cis"
represents substituents on the same side of the double bond and
"trans" represents substituents on opposite sides of the double
bond. The arrangement of substituents around a carbocyclic ring are
designated as "cis" or "trans." The term "cis" represents
substituents on the same side of the plane of the ring and the term
"trans" represents substituents on opposite sides of the plane of
the ring. Mixtures of compounds wherein the substituents are
disposed on both the same and opposite sides of plane of the ring
are designated "cis/trans."
[0031] The compounds disclosed herein can exist in solvated as well
as unsolvated forms with pharmaceutically acceptable solvents such
as water, ethanol, and the like, and it is intended that the
invention embrace both solvated and unsolvated forms. In one
embodiment, the compound is amorphous. In one embodiment, the
compound is a polymorph. In another embodiment, the compound is in
a crystalline form.
[0032] The invention also embraces isotopically labeled compounds
of the invention which are identical to those recited herein,
except that one or more atoms are replaced by an atom having an
atomic mass or mass number different from the atomic mass or mass
number usually found in nature. Examples of isotopes that can be
incorporated into compounds of the invention include isotopes of
hydrogen, carbon, nitrogen, oxygen, phosphorus, fluorine and
chlorine, such as .sup.2H, .sup.3H, .sup.13C, .sup.14C, .sup.15N,
.sup.18O, .sup.17O, .sup.31P, .sup.32P, .sup.35S, .sup.18F, and
.sup.36Cl, respectively.
[0033] Certain isotopically-labeled disclosed compounds (e.g.,
those labeled with .sup.3H and .sup.14C) are useful in compound
and/or substrate tissue distribution assays. Tritiated (i.e.,
.sup.3H) and carbon-14 (i.e., .sup.14C) isotopes are particularly
preferred for their ease of preparation and detectability. Further,
substitution with heavier isotopes such as deuterium (i.e.,
.sup.2H) may afford certain therapeutic advantages resulting from
greater metabolic stability (e.g., increased in vivo half-life or
reduced dosage requirements) and hence may be preferred in some
circumstances. Isotopically labeled compounds of the invention can
generally be prepared by following procedures analogous to those
disclosed in the e.g., Examples herein by substituting an
isotopically labeled reagent for a non-isotopically labeled
reagent.
[0034] As used in the present disclosure, "NMDA" is defined as
N-methyl-d-aspartate.
[0035] In the present specification, the term "therapeutically
effective amount" means the amount of the subject compound that
will elicit the biological or medical response of a tissue, system,
animal or human that is being sought by the researcher,
veterinarian, medical doctor or other clinician. The compounds of
the invention are administered in therapeutically effective amounts
to treat a disease. Alternatively, a therapeutically effective
amount of a compound is the quantity required to achieve a desired
therapeutic and/or prophylactic effect, such as an amount which
results in defined as that amount needed to give maximal
enhancement of a behavior (for example, learning), physiological
response (for example, LTP induction), or inhibition of neuropathic
pain.
Compounds
[0036] Disclosed compounds include those represented by the
formula:
##STR00002##
and pharmaceutically acceptable salts, stereoisomers, metabolites,
and hydrates thereof, wherein:
[0037] R.sup.1, R.sup.2, R.sup.3, and R.sup.4 may be independently
selected from the group consisting of hydrogen; halogen; cyclic or
acyclic, substituted or unsubstituted, branched or unbranched
aliphatic; cyclic or acyclic, substituted or unsubstituted,
branched or unbranched heteroaliphatic; substituted or
unsubstituted aryl; substituted or unsubstituted heteroaryl;
--OR.sup.x; --NO.sub.2; --N.sub.3; --CN; --SCN; --SR.sup.x;
--C(O)R.sup.x; --CO.sub.2(R.sup.x); --C(O)N(R.sup.x).sub.2;
--C(NR.sup.x)N(R.sup.x).sub.2; --OC(O)R.sup.x; --OCO.sub.2R.sup.x;
--OC(O)N(R.sup.x).sub.2; --N(R.sup.x).sub.2; --SOR.sup.x;
--S(O).sub.2R.sup.x; --NR.sup.xC(O)R.sup.x;
--NR.sup.xC(O)N(R.sup.x).sub.2; --NR.sup.xC(O)OR.sup.x;
--NR.sup.xC(NR.sup.x)N(R.sup.x).sub.2; and --C(R.sup.x).sub.3;
wherein each occurrence of R.sup.x is independently selected from
the group consisting of hydrogen; halogen; acyl; optionally
substituted aliphatic; optionally substituted heteroaliphatic;
optionally substituted aryl; and optionally substituted
heteroaryl;
[0038] R.sup.5 and R.sup.6 may be independently selected from the
group consisting of -Q-Ar and hydrogen, provided that at least one
of R.sup.5 and R.sup.6 is -Q-Ar; wherein Q is independently
selected from the group consisting of cyclic or acyclic,
substituted or unsubstituted, branched or unbranched aliphatic;
cyclic or acyclic, substituted or unsubstituted, branched or
unbranched heteroaliphatic; and a bond; and wherein Ar is selected
from the group consisting substituted or unsubstituted aryl, and
substituted or unsubstituted heteroaryl; or R.sup.5 and R.sup.6,
together with the atoms to which they are attached, form a
substituted or unsubstituted 4-6 membered heterocyclic or
cycloalkyl ring;
[0039] R.sup.7 and R.sup.8 may be independently selected from the
group consisting of hydrogen; halogen; hydroxyl; substituted or
unsubstituted C.sub.1-C.sub.6 alkyl; substituted or unsubstituted
C.sub.1-C.sub.6 alkoxy; and substituted or unsubstituted aryl; or
R.sup.7 and R.sup.8, together with the atoms to which they are
attached, form a substituted or unsubstituted 4-6 membered
heterocyclic or cycloalkyl ring;
[0040] R.sup.9 and R.sup.10 may be independently selected from the
group consisting of hydrogen; C.sub.1-C.sub.6 alkyl, optionally
substituted by one or more substituents each independently selected
from the group consisting of halogen, oxo, and hydroxyl;
C.sub.2-6alkenyl, optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, oxo, and hydroxyl; C.sub.2-6alkynyl, optionally
substituted by one or more substituents each independently selected
from the group consisting of halogen, oxo, and hydroxyl;
C.sub.3-6cycloalkyl, optionally substituted by one or more
substituents each independently selected from the group consisting
of C.sub.1-6alkyl, halogen, oxo, and hydroxyl; phenyl, optionally
substituted by one or more substituents each independently selected
from the group consisting of C.sub.1-6alkyl; C.sub.1-6alkoxy;
halogen; hydroxyl; --C(O)R.sup.x; --CO.sub.2(R.sup.x);
--C(O)N(R.sup.x).sub.2; --C(NR.sup.x)N(R.sup.x).sub.2; and
--C(R.sup.x).sub.3;
[0041] X is selected from the group consisting of OR.sup.x or
NR.sup.xR.sup.x; wherein each occurrence of R.sup.x is
independently selected from the group consisting of hydrogen;
halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl; C.sub.2-6alkynyl;
C.sub.3-6cycloalkyl; and phenyl; or R.sup.9 and R.sup.10, together
with N, form a 4-6 membered heterocyclic ring, optionally
substituted by one or more substituents each independently selected
from the group consisting of C.sub.1-6alkyl, halogen, oxo, and
hydroxyl.
[0042] In some embodiments, R.sup.1, R.sup.2, R.sup.3, and R.sup.4
may be independently selected from the group consisting of
hydrogen; halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; phenyl; naphthyl;
heteroaryl; heterocyclyl; C.sub.3-6 cycloalkyl-C.sub.1-6 alkyl-;
phenyl-C.sub.1-6 alkyl-; naphthyl-C.sub.1-6 alkyl-;
heteroaryl-C.sub.1-6alkyl-; and heterocyclyl-C.sub.1-6alkyl-;
--OR.sup.x; --NO.sub.2; --N.sub.3; --CN; --SCN; --SR.sup.x;
--C(O)R.sup.x; --CO.sub.2(R.sup.x); --C(O)N(R.sup.x).sub.2;
--C(NR.sup.x)N(R.sup.x).sub.2; --OC(O)R.sup.x; --OCO.sub.2R.sup.x;
--OC(O)N(R.sup.x).sub.2; --N(R.sup.x).sub.2; --SOR.sup.x;
--S(O).sub.2R.sup.x; --NR.sup.xC(O)R.sup.x;
--NR.sup.xC(O)N(R.sup.x).sub.2; --NR.sup.xC(O)OR.sup.x;
--NR.sup.xC(NR.sup.x)N(R.sup.x).sub.2; and --C(R.sup.x).sub.3;
wherein heteroaryl is a 5-6 membered ring having one, two, or three
heteroatoms each independently selected from N, O, or S; wherein
heteroaryl is optionally substituted with one or more substituents
each independently selected from R.sup.b; wherein heterocyclyl is a
4-7 membered ring optionally substituted by one or more
substituents each independently selected from R.sup.c; wherein when
heterocyclyl contains a NH moiety, that NH moiety is optionally
substituted by R.sup.d; wherein C.sub.2-6alkenyl and
C.sub.2-6alkynyl, are each independently optionally substituted by
one or more substituents each independently selected from R.sup.e;
wherein C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from R.sup.f; wherein
C.sub.3-6cycloalkyl is independently optionally substituted by one
or more substituents each independently selected from R.sup.g;
[0043] R.sup.b may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; C.sub.1-6alkoxy;
C.sub.3-6alkenyloxy; C.sub.3-6alkynyloxy; C.sub.3-6cycloalkoxy;
C.sub.1-6alkyl-S(O).sub.w--, where w is 0, 1, or 2; C.sub.1-6
alkylC.sub.3-6 cycloalkyl-; C.sub.3-6 cyclo alkyl-C.sub.1-6 alkyl-;
C.sub.1-6 alkoxycarbonyl-N(R.sup.a)--; C.sub.1-6 alkylN(R.sup.a)--;
C.sub.1-6 alkyl-N(R.sup.a)carbonyl-; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl-; R.sup.aR.sup.a'N-carbonyl-N(R.sup.a)--;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-6
alkyl-carbonyl-N(R.sup.a)--;
[0044] R.sup.a and R.sup.a' may be selected, independently for each
occurrence, from the group consisting of hydrogen and
C.sub.1-6alkyl, or R.sup.a and R.sup.a' when taken together with
the nitrogen to which they are attached form a 4-6 membered
heterocyclic ring, wherein C.sub.1-6alkyl is optionally substituted
by one or more substituents each independently selected from the
group consisting of halogen, oxo, and hydroxyl, and wherein the
heterocyclic ring is optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, alkyl, oxo, or hydroxyl;
[0045] R.sup.c may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; oxo; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; C.sub.1-6alkoxy;
C.sub.3-6alkenyloxy; C.sub.3-6alkynyloxy; C.sub.3-6cycloalkoxy;
C.sub.1-6alkyl-S(O).sub.w--, where w is 0, 1, or 2; C.sub.1-6
alkylC.sub.3-6 cycloalkyl-; C.sub.3-6 cyclo alkyl-C.sub.1-6 alkyl-;
C.sub.1-6 alkoxycarbonyl-N(R.sup.a)--; C.sub.1-6 alkylN(R.sup.a)--;
C.sub.1-6 alkyl-N(R.sup.a)carbonyl-; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl-; R.sup.aR.sup.a'N-carbonyl-N(R.sup.a)--;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-6
alkyl-carbonyl-N(R.sup.a)--;
[0046] R.sup.d may be selected, independently for each occurrence,
from the group consisting of C.sub.1-6alkyl,
C.sub.1-6alkylcarbonyl, and C.sub.1-6alkylsulfonyl, wherein
C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from halogen, hydroxyl,
and R.sup.aR.sup.a'N--;
[0047] R.sup.e may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-4alkoxy; C.sub.1-4alkoxycarbonyl;
R.sup.aR.sup.a'N--; R.sup.aR.sup.a'N-carbonyl;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-4alkylS(O).sub.w--, where
w is 0, 1, or 2;
[0048] R.sup.f may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-4alkoxy; C.sub.1-4alkoxycarbonyl;
R.sup.aR.sup.a'N--; R.sup.aR.sup.a'N-carbonyl;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-4alkylS(O).sub.w--, where
w is 0, 1, or 2;
[0049] R.sup.g may be selected, independently for each occurrence,
from the group consisting of halogen, hydroxyl, --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.1-4alkoxy;
C.sub.1-4alkoxycarbonyl; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl; R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-4alkylS(O).sub.w--, where w is 0, 1, or 2;
[0050] R.sup.x may be selected, independently, from the group
consisting of hydrogen; halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; phenyl; naphthyl;
heteroaryl; heterocyclyl; C.sub.3-6 cycloalkyl-C.sub.1-6 alkyl-;
phenyl-C.sub.1-6alkyl-; naphthyl-C.sub.1-6 alkyl-;
heteroaryl-C.sub.1-6 alkyl-; and heterocyclyl-C.sub.1-6alkyl-;
wherein heteroaryl is a 5-6 membered ring having one, two, or three
heteroatoms each independently selected from N, O, or S; wherein
heteroaryl is optionally substituted with one or more substituents
each independently selected from R.sup.b; wherein heterocyclyl is a
4-7 membered ring optionally substituted by one or more
substituents each independently selected from R.sup.c; wherein when
heterocyclyl contains a NH moiety, that NH moiety is optionally
substituted by R.sup.d; wherein C.sub.2-6alkenyl and
C.sub.2-6alkynyl, are each independently optionally substituted by
one or more substituents each independently selected from R.sup.e;
wherein C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from R.sup.f; wherein
C.sub.3-6cycloalkyl is independently optionally substituted by one
or more substituents each independently selected from R.sup.g.
[0051] In certain embodiments, at least one of R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 may be hydroxyl.
[0052] In some instances, at least one of R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 may be C.sub.1-C.sub.6 alkyl, optionally
substituted with one, two, or three substituents selected
independently from the group consisting of halogen, hydroxyl,
--NH.sub.2, and cyano.
[0053] In some embodiments, at least one of R.sup.5 and R.sup.6 may
be --(C.sub.1-C.sub.6 alkylene)-Ar. At least one of R.sup.5 and
R.sup.6 may also be --CH.sub.2--Ar. In some cases, at least one of
R.sup.5 and R.sup.6 is -Q-phenyl. In certain examples, one of
R.sup.5 and R.sup.6 may be hydrogen.
[0054] In some cases, R.sup.7 and R.sup.8 may be independently
selected from the group consisting of hydrogen; halogen; hydroxyl;
C.sub.1-C.sub.6 alkyl; phenyl; and naphthyl; or R.sup.7 and
R.sup.8, together with the atoms to which they are attached, form a
4-6 membered heterocyclic or cycloalkyl ring; wherein
C.sub.1-C.sub.6 alkyl, phenyl, naphthyl, the cycloalkyl ring, and
the heterocyclic ring each may be substituted independently by one
or more substituents selected from the group consisting of halogen;
hydroxyl; --NO.sub.2; --N.sub.3; --CN; --SCN; C.sub.1-4alkoxy;
C.sub.1-4alkoxycarbonyl; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl; R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-4alkylS(O).sub.w--, where w is 0, 1, or 2; wherein R.sup.a
and R.sup.a' may be selected, independently for each occurrence,
from the group consisting of hydrogen and C.sub.1-6alkyl, or
R.sup.a and R.sup.a' when taken together with the nitrogen to which
they are attached form a 4-6 membered heterocyclic ring, wherein
C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, oxo, and hydroxyl, and wherein the heterocyclic ring is
optionally substituted by one or more substituents each
independently selected from the group consisting of halogen, alkyl,
oxo, or hydroxyl.
[0055] In some cases, R.sup.7 and R.sup.8 may be hydrogen.
[0056] X may be, for example, selected from the group consisting of
OH and NH.sub.2.
[0057] In an exemplary embodiment, a compound may be represented
by:
##STR00003##
wherein X is OH or NH.sub.2.
[0058] In an exemplary embodiment, a compound may be represented
by:
##STR00004##
[0059] In another exemplary embodiment, a compound may be
represented by:
##STR00005##
[0060] In yet another exemplary embodiment, a compound may be
represented by:
##STR00006##
[0061] Provided herein, for example, is a compound represented
by:
##STR00007##
[0062] wherein X is OH or NH.sub.2, and pharmaceutically acceptable
salts thereof.
[0063] Disclosed compounds also include those represented by the
formula:
##STR00008##
and pharmaceutically acceptable salts, stereoisomers, metabolites,
and hydrates thereof, wherein:
[0064] R.sup.1 and R.sup.3 may be independently selected from the
group consisting of hydrogen; halogen; cyclic or acyclic,
substituted or unsubstituted, branched or unbranched aliphatic;
cyclic or acyclic, substituted or unsubstituted, branched or
unbranched heteroaliphatic; substituted or unsubstituted aryl;
substituted or unsubstituted heteroaryl; --OR.sup.x; --NO.sub.2;
--N.sub.3; --CN; --SCN; --SR.sup.x; --C(O)R.sup.x;
--CO.sub.2(R.sup.x); --C(O)N(R.sup.x).sub.2;
--C(NR.sup.x)N(R.sup.x).sub.2; --OC(O)R.sup.x; --OCO.sub.2R.sup.x;
--OC(O)N(R.sup.x).sub.2; --N(R.sup.x).sub.2; --SOR.sup.x;
--S(O).sub.2R.sup.x; --NR.sup.xC(O)R.sup.x;
--NR.sup.xC(O)N(R.sup.x).sub.2; --NR.sup.xC(O)OR.sup.x;
--NR.sup.xC(NR.sup.x)N(R.sup.x).sub.2; and --C(R.sup.x).sub.3;
wherein each occurrence of R.sup.x is independently selected from
the group consisting of hydrogen; halogen; acyl; optionally
substituted aliphatic; optionally substituted heteroaliphatic;
optionally substituted aryl; and optionally substituted
heteroaryl;
[0065] R.sup.2 and R.sup.4 may be independently selected from the
group consisting of hydrogen and --OR.sup.x, provided that at least
one of R.sup.2 and R.sup.4 is hydrogen, wherein R.sup.x is selected
from the group consisting of hydrogen; halogen; acyl; optionally
substituted aliphatic; optionally substituted heteroaliphatic;
optionally substituted aryl; and optionally substituted
heteroaryl;
[0066] R.sup.5 and R.sup.6 may be independently selected from the
group consisting of -Q-Ar and hydrogen; wherein Q is independently
selected from the group consisting of cyclic or acyclic,
substituted or unsubstituted, branched or unbranched aliphatic;
cyclic or acyclic, substituted or unsubstituted, branched or
unbranched heteroaliphatic; and a bond; and wherein Ar is selected
from the group consisting substituted or unsubstituted aryl, and
substituted or unsubstituted heteroaryl; or R.sup.5 and R.sup.6,
together with the atoms to which they are attached, form a
substituted or unsubstituted 4-6 membered heterocyclic or
cycloalkyl ring;
[0067] R.sup.7 and R.sup.8 are independently selected from the
group consisting of hydrogen; halogen; hydroxyl; substituted or
unsubstituted C.sub.1-C.sub.6 alkyl; substituted or unsubstituted
C.sub.1-C.sub.6 alkoxy; and substituted or unsubstituted aryl; or
R.sup.7 and R.sup.8, together with the atoms to which they are
attached, form a substituted or unsubstituted 4-6 membered
heterocyclic or cycloalkyl ring;
[0068] R.sup.9 and R.sup.10 may be independently selected from the
group consisting of hydrogen; C.sub.1-C.sub.6 alkyl, optionally
substituted by one or more substituents each independently selected
from the group consisting of halogen, oxo, and hydroxyl;
C.sub.2-6alkenyl, optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, oxo, and hydroxyl; C.sub.2-6alkynyl, optionally
substituted by one or more substituents each independently selected
from the group consisting of halogen, oxo, and hydroxyl;
C.sub.3-6cycloalkyl, optionally substituted by one or more
substituents each independently selected from the group consisting
of C.sub.1-6alkyl, halogen, oxo, and hydroxyl; phenyl, optionally
substituted by one or more substituents each independently selected
from the group consisting of C.sub.1-6alkyl; C.sub.1-6alkoxy;
halogen; hydroxyl; --C(O)R.sup.x; --CO.sub.2(R.sup.x);
--C(O)N(R.sup.x).sub.2; --C(NR.sup.x)N(R.sup.x).sub.2; and
--C(R.sup.x).sub.3; wherein each occurrence of R.sup.x is
independently selected from the group consisting of hydrogen;
halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl; C.sub.2-6alkynyl;
C.sub.3-6cycloalkyl; and phenyl; or R.sup.9 and R.sup.10, together
with N, form a 4-6 membered heterocyclic ring, optionally
substituted by one or more substituents each independently selected
from the group consisting of C.sub.1-6alkyl, halogen, oxo, and
hydroxyl.
[0069] In some embodiments, R.sup.1 and R.sup.3 may be
independently selected from the group consisting of hydrogen;
halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl; C.sub.2-6alkynyl;
C.sub.3-6cycloalkyl; phenyl; naphthyl; heteroaryl; heterocyclyl;
C.sub.3-6 cycloalkyl-C.sub.1-6 alkyl-; phenyl-C.sub.1-6 alkyl-;
naphthyl-C.sub.1-6 alkyl-; heteroaryl-C.sub.1-6alkyl-; and
heterocyclyl-C.sub.1-6alkyl-; --OR.sup.x; --NO.sub.2; --N.sub.3;
--CN; --SCN; --SR.sup.x; --C(O)R.sup.x; --CO.sub.2(R.sup.x);
--C(O)N(R.sup.x).sub.2; --C(NR.sup.x)N(R.sup.x).sub.2;
--OC(O)R.sup.x; --OCO.sub.2R.sup.x; --OC(O)N(R.sup.x).sub.2;
--N(R.sup.x).sub.2; --SOR.sup.x; --S(O).sub.2R.sup.x;
--NR.sup.xC(O)R.sup.x; --NR.sup.xC(O)N(R.sup.x).sub.2;
--NR.sup.xC(O)OR.sup.x; --NR.sup.xC(NR.sup.x)N(R.sup.x).sub.2; and
--C(R.sup.x).sub.3; wherein heteroaryl is a 5-6 membered ring
having one, two, or three heteroatoms each independently selected
from N, O, or S; wherein heteroaryl is optionally substituted with
one or more substituents each independently selected from R.sup.b;
wherein heterocyclyl is a 4-7 membered ring optionally substituted
by one or more substituents each independently selected from
R.sup.c; wherein when heterocyclyl contains a NH moiety, that NH
moiety is optionally substituted by R.sup.d; wherein
C.sub.2-6alkenyl and C.sub.2-6alkynyl, are each independently
optionally substituted by one or more substituents each
independently selected from R.sup.e; wherein C.sub.1-6alkyl is
optionally substituted by one or more substituents each
independently selected from R.sup.f; wherein C.sub.3-6cycloalkyl is
independently optionally substituted by one or more substituents
each independently selected from R.sup.g;
[0070] R.sup.b may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; C.sub.1-6alkoxy;
C.sub.3-6alkenyloxy; C.sub.3-6alkynyloxy; C.sub.3-6cycloalkoxy;
C.sub.1-6alkyl-S(O).sub.w--, where w is 0, 1, or 2; C.sub.1-6
alkylC.sub.3-6 cycloalkyl-; C.sub.3-6 cycloalkyl-C.sub.1-6 alkyl-;
C.sub.1-6 alkoxycarbonyl-N(R.sup.a)--; C.sub.1-6 alkylN(R.sup.a)--;
C.sub.1-6 alkyl-N(R.sup.a)carbonyl-; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl-; R.sup.aR.sup.a'N-carbonyl-N(R.sup.a)--;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-6
alkyl-carbonyl-N(R.sup.a)--;
[0071] R.sup.a and R.sup.a' may be selected, independently for each
occurrence, from the group consisting of hydrogen and
C.sub.1-6alkyl, or R.sup.a and R.sup.a' when taken together with
the nitrogen to which they are attached form a 4-6 membered
heterocyclic ring, wherein C.sub.1-6alkyl is optionally substituted
by one or more substituents each independently selected from the
group consisting of halogen, oxo, and hydroxyl, and wherein the
heterocyclic ring is optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, alkyl, oxo, or hydroxyl;
[0072] R.sup.c may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; oxo; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; C.sub.1-6alkoxy;
C.sub.3-6alkenyloxy; C.sub.3-6alkynyloxy; C.sub.3-6cycloalkoxy;
C.sub.1-6alkyl-S(O).sub.w--, where w is 0, 1, or 2; C.sub.1-6
alkylC.sub.3-6 cycloalkyl-; C.sub.3-6 cyclo alkyl-C.sub.1-6 alkyl-;
C.sub.1-6 alkoxycarbonyl-N(R.sup.a)--; C.sub.1-6 alkylN(R.sup.a)--;
C.sub.1-6alkyl-N(R.sup.a)carbonyl-; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl-; R.sup.aR.sup.a'N-carbonyl-N(R.sup.a)--;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-6
alkyl-carbonyl-N(R.sup.a)--;
[0073] R.sup.d may be selected, independently for each occurrence,
from the group consisting of C.sub.1-6alkyl,
C.sub.1-6alkylcarbonyl, and C.sub.1-6alkylsulfonyl, wherein
C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from halogen, hydroxyl,
and R.sup.aR.sup.a'N--;
[0074] R.sup.e may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-4alkoxy; C.sub.1-4alkoxycarbonyl;
R.sup.aR.sup.a'N--; R.sup.aR.sup.a'N-carbonyl;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-4alkylS(O).sub.w--, where
w is 0, 1, or 2;
[0075] R.sup.f may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-4alkoxy; C.sub.1-4alkoxycarbonyl;
R.sup.aR.sup.a'N--; R.sup.aR.sup.a'N-carbonyl;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-4alkylS(O).sub.w--, where
w is 0, 1, or 2;
[0076] R.sup.g may be selected, independently for each occurrence,
from the group consisting of halogen, hydroxyl, --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.1-4alkoxy;
C.sub.1-4alkoxycarbonyl; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl; R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-4alkylS(O).sub.w--, where w is 0, 1, or 2;
[0077] R.sup.x may be selected, independently, from the group
consisting of hydrogen; halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; phenyl; naphthyl;
heteroaryl; heterocyclyl; C.sub.3-6 cycloalkyl-C.sub.1-6 alkyl-;
phenyl-C.sub.1-6alkyl-; naphthyl-C.sub.1-6 alkyl-;
heteroaryl-C.sub.1-6 alkyl-; and heterocyclyl-C.sub.1-6alkyl-;
wherein heteroaryl is a 5-6 membered ring having one, two, or three
heteroatoms each independently selected from N, O, or S; wherein
heteroaryl is optionally substituted with one or more substituents
each independently selected from R.sup.b; wherein heterocyclyl is a
4-7 membered ring optionally substituted by one or more
substituents each independently selected from R.sup.c; wherein when
heterocyclyl contains a NH moiety, that NH moiety is optionally
substituted by R.sup.d; wherein C.sub.2-6alkenyl and
C.sub.2-6alkynyl, are each independently optionally substituted by
one or more substituents each independently selected from R.sup.e;
wherein C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from R.sup.f; wherein
C.sub.3-6cycloalkyl is independently optionally substituted by one
or more substituents each independently selected from R.sup.g.
[0078] In some cases, R.sup.2 and R.sup.4 may be independently
selected from the group consisting of hydrogen and --OR.sup.x,
provided that at least one of R.sup.2 and R.sup.4 is hydrogen,
wherein R.sup.x may be selected from the group consisting of
hydrogen; halogen; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; phenyl; naphthyl;
heteroaryl; heterocyclyl; C.sub.3-6cycloalkyl-C.sub.1-6alkyl-;
phenyl-C.sub.1-6alkyl-; naphthyl-C.sub.1-6alkyl-;
heteroaryl-C.sub.1-6alkyl-; and heterocyclyl-C.sub.1-6alkyl-;
wherein heteroaryl is a 5-6 membered ring having one, two, or three
heteroatoms each independently selected from N, O, or S; wherein
heteroaryl is optionally substituted with one or more substituents
each independently selected from R.sup.b; wherein heterocyclyl is a
4-7 membered ring optionally substituted by one or more
substituents each independently selected from R.sup.c; wherein when
heterocyclyl contains a NH moiety, that NH moiety is optionally
substituted by R.sup.d; wherein C.sub.2-6alkenyl and
C.sub.2-6alkynyl, are each independently optionally substituted by
one or more substituents each independently selected from R.sup.e;
wherein C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from R.sup.f; wherein
C.sub.3-6cycloalkyl is independently optionally substituted by one
or more substituents each independently selected from R.sup.g;
[0079] R.sup.b may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; C.sub.1-6alkoxy;
C.sub.3-6alkenyloxy; C.sub.3-6alkynyloxy; C.sub.3-6cycloalkoxy;
C.sub.1-6alkyl-S(O).sub.w--, where w is 0, 1, or 2;
C.sub.1-6alkylC.sub.3-6cycloalkyl-;
C.sub.3-6cycloalkyl-C.sub.1-6alkyl-;
C.sub.1-6alkoxycarbonyl-N(R.sup.a)--; C.sub.1-6alkylN(R.sup.a)--;
C.sub.1-6alkyl-N(R.sup.a)carbonyl-; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl-; R.sup.aR.sup.a'N-carbonyl-N(R.sup.a)--;
R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-6alkyl-carbonyl-N(R.sup.a)--;
[0080] R.sup.a and R.sup.a' may be selected, independently for each
occurrence, from the group consisting of hydrogen and
C.sub.1-6alkyl, or R.sup.a and R.sup.a' when taken together with
the nitrogen to which they are attached form a 4-6 membered
heterocyclic ring, wherein C.sub.1-6alkyl is optionally substituted
by one or more substituents each independently selected from the
group consisting of halogen, oxo, and hydroxyl, and wherein the
heterocyclic ring is optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, alkyl, oxo, or hydroxyl;
[0081] R.sup.c may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; oxo; C.sub.1-6alkyl; C.sub.2-6alkenyl;
C.sub.2-6alkynyl; C.sub.3-6cycloalkyl; C.sub.1-6alkoxy;
C.sub.3-6alkenyloxy; C.sub.3-6alkynyloxy; C.sub.3-6cycloalkoxy;
C.sub.1-6alkyl-S(O).sub.w--, where w is 0, 1, or 2; C.sub.1-6
alkylC.sub.3-6 cycloalkyl-; C.sub.3-6 cyclo alkyl-C.sub.1-6 alkyl-;
C.sub.1-6 alkoxycarbonyl-N(R.sup.a)--; C.sub.1-6 alkylN(R.sup.a)--;
C.sub.1-6 alkyl-N(R.sup.a)carbonyl-; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl-; R.sup.aR.sup.a'N-carbonyl-N(R.sup.a)--;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-6
alkyl-carbonyl-N(R.sup.a)--;
[0082] R.sup.d may be selected, independently for each occurrence,
from the group consisting of C.sub.1-6alkyl,
C.sub.1-6alkylcarbonyl, and C.sub.1-6alkylsulfonyl, wherein
C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from halogen, hydroxyl,
and R.sup.aR.sup.a'N--;
[0083] R.sup.e may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-4alkoxy; C.sub.1-4alkoxycarbonyl;
R.sup.aR.sup.a'N--; R.sup.aR.sup.a'N-carbonyl;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-4alkylS(O).sub.w--, where
w is 0, 1, or 2;
[0084] R.sup.f may be selected, independently for each occurrence,
from the group consisting of halogen; hydroxyl; --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-4alkoxy; C.sub.1-4alkoxycarbonyl;
R.sup.aR.sup.a'N--; R.sup.aR.sup.a'N-carbonyl;
R.sup.aR.sup.a'N--SO.sub.2--; and C.sub.1-4alkylS(O).sub.w--, where
w is 0, 1, or 2;
[0085] R.sup.g may be selected, independently for each occurrence,
from the group consisting of halogen, hydroxyl, --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.1-4alkoxy;
C.sub.1-4alkoxycarbonyl; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl; R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-4alkylS(O).sub.w--, where w is 0, 1, or 2.
[0086] In certain embodiments, R.sup.5 and R.sup.6 may be
independently selected from the group consisting of -Q-Ar and
hydrogen; wherein Q is independently selected from the group
consisting of C.sub.1-6alkyl; C.sub.2-6alkenyl; C.sub.2-6alkynyl;
C.sub.3-6cycloalkyl; heterocyclyl;
C.sub.3-6cycloalkyl-C.sub.1-6alkyl-; heterocyclyl-C.sub.1-6alkyl-;
and a bond; and wherein Ar is selected from the group consisting
substituted or unsubstituted phenyl, naphthyl, and heteroaryl; or
R.sup.5 and R.sup.6, together with the atoms to which they are
attached, form a 4-6 membered heterocyclic or cycloalkyl ring,
optionally substituted by one or more substituents each
independently selected from halogen, hydroxyl, --NO.sub.2;
--N.sub.3; --CN; --SCN; C.sub.1-6alkyl; C.sub.1-4alkoxy;
C.sub.1-4alkoxycarbonyl; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl; R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-4alkylS(O).sub.w--, where w is 0, 1, or 2; and
[0087] wherein R.sup.a and R.sup.a' may be selected, independently
for each occurrence, from the group consisting of hydrogen and
C.sub.1-6alkyl, or R.sup.a and R.sup.a' when taken together with
the nitrogen to which they are attached form a 4-6 membered
heterocyclic ring, wherein C.sub.1-6alkyl is optionally substituted
by one or more substituents each independently selected from the
group consisting of halogen, oxo, and hydroxyl, and wherein the
heterocyclic ring is optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, alkyl, oxo, or hydroxyl.
[0088] In certain embodiments, at least one of R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 may be hydroxyl.
[0089] In some instances, at least one of R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 may be C.sub.1-C.sub.6 alkyl, optionally
substituted with one, two, or three substituents selected
independently from the group consisting of halogen, hydroxyl,
--NH.sub.2, and cyano.
[0090] In some embodiments, at least one of R.sup.5 and R.sup.6 may
be --(C.sub.1-C.sub.6 alkylene)-Ar. At least one of R.sup.5 and
R.sup.6 may also be --CH.sub.2--Ar. In some cases, at least one of
R.sup.5 and R.sup.6 is -Q-phenyl. In certain examples, one of
R.sup.5 and R.sup.6 may be hydrogen.
[0091] In some cases, R.sup.7 and R.sup.8 may be independently
selected from the group consisting of hydrogen; halogen; hydroxyl;
C.sub.1-C.sub.6 alkyl; phenyl; and naphthyl; or R.sup.7 and
R.sup.8, together with the atoms to which they are attached, form a
4-6 membered heterocyclic or cycloalkyl ring; wherein
C.sub.1-C.sub.6 alkyl, phenyl, naphthyl, the cycloalkyl ring, and
the heterocyclic ring each may be substituted independently by one
or more substituents selected from the group consisting of halogen;
hydroxyl; --NO.sub.2; --N.sub.3; --CN; --SCN; C.sub.1-4alkoxy;
C.sub.1-4alkoxycarbonyl; R.sup.aR.sup.a'N--;
R.sup.aR.sup.a'N-carbonyl; R.sup.aR.sup.a'N--SO.sub.2--; and
C.sub.1-4alkylS(O).sub.w--, where w is 0, 1, or 2; wherein R.sup.a
and R.sup.a' may be selected, independently for each occurrence,
from the group consisting of hydrogen and C.sub.1-6alkyl, or
R.sup.a and R.sup.a' when taken together with the nitrogen to which
they are attached form a 4-6 membered heterocyclic ring, wherein
C.sub.1-6alkyl is optionally substituted by one or more
substituents each independently selected from the group consisting
of halogen, oxo, and hydroxyl, and wherein the heterocyclic ring is
optionally substituted by one or more substituents each
independently selected from the group consisting of halogen, alkyl,
oxo, or hydroxyl.
[0092] In some cases, R.sup.7 and R.sup.8 may be hydrogen.
[0093] In an exemplary embodiment, a compound may be represented
by:
##STR00009##
[0094] In another exemplary embodiment, a compound may be
represented by:
##STR00010##
[0095] In yet another exemplary embodiment, a compound may be
represented by:
##STR00011##
[0096] For example, provided herein is a compound represented
by:
##STR00012##
wherein:
[0097] R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each
independently selected from the group consisting of hydrogen;
halogen, C.sub.1-C.sub.6alkyl, or OH;
[0098] R.sup.5 is selected from the group consisting of
--CH.sub.2-phenyl and hydrogen, provided that R.sup.5 is
--CH.sub.2-phenyl when R.sub.1 and R.sub.3 are OH and R.sub.2 and
R.sub.4 are methyl;
[0099] X is selected from the group consisting of OR.sup.x and
NR.sup.xR.sup.x, wherein R.sup.x is independently selected, for
each occurrence, from the group consisting of hydrogen, and
C.sub.1-C.sub.6alkyl; and pharmaceutically acceptable salts,
stereoisomers, and hydrates thereof.
[0100] The compounds of the present disclosure and formulations
thereof may have a plurality of chiral centers. Each chiral center
may be independently R, S, or any mixture of R and S. For example,
in some embodiments, a chiral center may have an R:S ratio of
between about 100:0 and about 50:50, between about 100:0 and about
75:25, between about 100:0 and about 85:15, between about 100:0 and
about 90:10, between about 100:0 and about 95:5, between about
100:0 and about 98:2, between about 100:0 and about 99:1, between
about 0:100 and 50:50, between about 0:100 and about 25:75, between
about 0:100 and about 15:85, between about 0:100 and about 10:90,
between about 0:100 and about 5:95, between about 0:100 and about
2:98, between about 0:100 and about 1:99, between about 75:25 and
25:75, and about 50:50. Formulations of the disclosed compounds
comprising a greater ratio of one or more isomers (i.e., R and/or
S) may possess enhanced therapeutic characteristic relative to
racemic formulations of a disclosed compounds or mixture of
compounds.
[0101] Disclosed compounds may provide for efficient cation channel
opening at the NMDA receptor, e.g. may bind or associate with the
glutamate site of the NMDA receptor to assist in opening the cation
channel. The disclosed compounds may be used to regulate (turn on
or turn off) the NMDA receptor through action as an agonist.
[0102] The compounds as described herein may be glycine site NMDA
receptor partial agonists. A partial agonist as used in this
context will be understood to mean that at a low concentration, the
analog acts as an agonist and at a high concentration, the analog
acts as an antagonist. Glycine binding is not inhibited by
glutamate or by competitive inhibitors of glutamate, and also does
not bind at the same site as glutamate on the NMDA receptor. A
second and separate binding site for glycine exists at the NMDA
receptor. The ligand-gated ion channel of the NMDA receptor is,
thus, under the control of at least these two distinct allosteric
sites. Disclosed compounds may be capable of binding or associating
with the glycine binding site of the NMDA receptor. In some
embodiments, disclosed compounds may possess a potency that is
10-fold or greater than the activity of existing NMDA receptor
glycine site partial agonists. For example, disclosed compounds may
possess a 10-fold to 20-fold enhanced potency compared to GLYX-13.
GLYX-13 is represented by:
##STR00013##
[0103] For example, provided herein are compounds that may be at
least about 20-fold more potent as compared to GLYX-13, as measured
by burst activated NMDA receptorgated single neuron conductance
(I.sub.NMDA) in a culture of hippocampal CA1 pyramidal neurons at a
concentration of 50 nM. In another embodiment, a provided compound
may be capable of generating an enhanced single shock evoked NMDA
receptor-gated single neuron conductance (I.sub.NMDA) in
hippocampal CA1 pyramidal neurons at concentrations of 100 nM to 1
.mu.M. Disclosed compounds may have enhanced potency as compared to
GLYX-13 as measured by magnitude of long term potentiation (LTP) at
Schaffer collateral-CA-1 synapses in in vitro hippocampal
slices.
[0104] The disclosed compounds may exhibit a high therapeutic
index. The therapeutic index, as used herein, refers to the ratio
of the dose that produces a toxicity in 50% of the population
(i.e., TD.sub.50) to the minimum effective dose for 50% of the
population (i.e., ED.sub.50). Thus, the therapeutic
index=(TD.sub.50):(ED.sub.50). In some embodiments, a disclosed
compound may have a therapeutic index of at least about 10:1, at
least about 50:1, at least about 100:1, at least about 200:1, at
least about 500:1, or at least about 1000:1.
Compositions
[0105] In other aspects, formulations and compositions comprising
the disclosed compounds and optionally a pharmaceutically
acceptable excipient are provided. In some embodiments, a
contemplated formulation comprises a racemic mixture of one or more
of the disclosed compounds.
[0106] Contemplated formulations may be prepared in any of a
variety of forms for use. By way of example, and not limitation,
the compounds may be prepared in a formulation suitable for oral
administration, subcutaneous injection, or other methods for
administering an active agent to an animal known in the
pharmaceutical arts.
[0107] Amounts of a disclosed compound as described herein in a
formulation may vary according to factors such as the disease
state, age, sex, and weight of the individual. Dosage regimens may
be adjusted to provide the optimum therapeutic response. For
example, a single bolus may be administered, several divided doses
may be administered over time or the dose may be proportionally
reduced or increased as indicated by the exigencies of the
therapeutic situation. It is especially advantageous to formulate
parenteral compositions in dosage unit form for ease of
administration and uniformity of dosage. Dosage unit form as used
herein refers to physically discrete units suited as unitary
dosages for the mammalian subjects to be treated; each unit
containing a predetermined quantity of active compound calculated
to produce the desired therapeutic effect in association with the
required pharmaceutical carrier.
[0108] The specification for the dosage unit forms of the invention
are dictated by and directly dependent on (a) the unique
characteristics of the compound selected and the particular
therapeutic effect to be achieved, and (b) the limitations inherent
in the art of compounding such an active compound for the treatment
of sensitivity in individuals.
[0109] Therapeutic compositions typically must be sterile and
stable under the conditions of manufacture and storage. The
composition can be formulated as a solution, microemulsion,
liposome, or other ordered structure suitable to high drug
concentration. The carrier can be a solvent or dispersion medium
containing, for example, water, ethanol, polyol (for example,
glycerol, propylene glycol, and liquid polyethylene glycol, and the
like), and suitable mixtures thereof. The proper fluidity can be
maintained, for example, by the use of a coating such as lecithin,
by the maintenance of the required particle size in the case of
dispersion and by the use of surfactants. In many cases, it will be
preferable to include isotonic agents, for example, sugars,
polyalcohols such as mannitol, sorbitol, or sodium chloride in the
composition. Prolonged absorption of the injectable compositions
can be brought about by including in the composition an agent which
delays absorption, for example, monostearate salts and gelatin.
[0110] The compounds can be administered in a time release
formulation, for example in a composition which includes a slow
release polymer. The compounds can be prepared with carriers that
will protect the compound against rapid release, such as a
controlled release formulation, including implants and
microencapsulated delivery systems. Biodegradable, biocompatible
polymers can be used, such as ethylene vinyl acetate,
polyanhydrides, polyglycolic acid, collagen, polyorthoesters,
polylactic acid and polylactic, polyglycolic copolymers (PLG). Many
methods for the preparation of such formulations are generally
known to those skilled in the art.
[0111] Sterile injectable solutions can be prepared by
incorporating the compound in the required amount in an appropriate
solvent with one or a combination of ingredients enumerated above,
as required, followed by filtered sterilization. Generally,
dispersions are prepared by incorporating the active compound into
a sterile vehicle which contains a basic dispersion medium and the
required other ingredients from those enumerated above. In the case
of sterile powders for the preparation of sterile injectable
solutions, the preferred methods of preparation are vacuum drying
and freeze-drying which yields a powder of the active ingredient
plus any additional desired ingredient from a previously
sterile-filtered solution thereof.
[0112] In accordance with an alternative aspect of the invention, a
compound may be formulated with one or more additional compounds
that enhance the solubility of the compound.
Methods
[0113] Methods for treating cognitive disorders and for enhancing
learning are provided. Such methods include administering a
pharmaceutically acceptable formulation of one or more of the
disclosed compounds to a patient in need thereof. Also contemplated
are methods of treating patients suffering from, memory deficits
associated with aging, schizophrenia, special learning disorders,
seizures, post-stroke convulsions, brain ischemia, hypoglycemia,
cardiac arrest, epilepsy, migraine, as well as Huntington's,
Parkinson's and Alzheimer's disease.
[0114] Other methods contemplated include the treatment of cerebral
ischemia, stroke, brain trauma, brain tumors, acute neuropathic
pain, chronic neuropathic pain, sleep disorders, drug addiction,
depression, certain vision disorders, ethanol withdrawal, anxiety,
memory and learning disabilities, autism, epilepsy, AIDS dementia,
multiple system atrophy, progressive supra-nuclear palsy,
Friedrich's ataxia, Down's syndrome, fragile X syndrome, tuberous
sclerosis, olivio-ponto-cerebellar atrophy, cerebral palsy,
drug-induced optic neuritis, peripheral neuropathy, myelopathy,
ischemic retinopathy, diabetic retinopathy, glaucoma, cardiac
arrest, behavior disorders, impulse control disorders, Alzheimer's
disease, memory loss that accompanies early stage Alzheimer's
disease, attention deficit disorder, ADHD, schizophrenia,
amelioration of opiate, nicotine addiction, ethanol addition,
traumatic brain injury, spinal cord injury, post-traumatic stress
syndrome, and Huntington's chorea.
[0115] For example, provided herein is a method of treating
depression in a patient need thereof, comprising administering a
disclosed compound, e.g by acutely administering a disclosed
compound. In certain embodiments, the treatment-resistant patient
is identified as one who has been treated with at least two types
of antidepressant treatments prior to administration of a disclosed
compound. In other embodiments, the treatment-resistant patient is
one who is identified as unwilling or unable to tolerate a side
effect of at least one type of antidepressant treatment.
[0116] The most common depression conditions include Major
Depressive Disorder and Dysthymic Disorder. Other depression
conditions develop under unique circumstances. Such depression
conditions include but are not limited to Psychotic depression,
Postpartum depression, Seasonal affective disorder (SAD), mood
disorder, depressions caused by chronic medical conditions such as
cancer or chronic pain, chemotherapy, chronic stress, post
traumatic stress disorders, and Bipolar disorder (or manic
depressive disorder).
[0117] Refractory depression occurs in patients suffering from
depression who are resistant to standard pharmacological
treatments, including tricyclic antidepressants, MAOIs, SSRIs, and
double and triple uptake inhibitors and/or anxiolytic drugs, as
well non-pharmacological treatments such as psychotherapy,
electroconvulsive therapy, vagus nerve stimulation and/or
transcranial magnetic stimulation. A treatment resistant-patient
may be identified as one who fails to experience alleviation of one
or more symptoms of depression (e.g., persistent anxious or sad
feelings, feelings of helplessness, hopelessness, pessimism)
despite undergoing one or more standard pharmacological or
non-pharmacological treatment. In certain embodiments, a
treatment-resistant patient is one who fails to experience
alleviation of one or more symptoms of depression despite
undergoing treatment with two different antidepressant drugs. In
other embodiments, a treatment-resistant patient is one who fails
to experience alleviation of one or more symptoms of depression
despite undergoing treatment with four different antidepressant
drugs. A treatment-resistant patient may also be identified as one
who is unwilling or unable to tolerate the side effects of one or
more standard pharmacological or non-pharmacological treatment.
[0118] In yet another aspect, a method for enhancing pain relief
and for providing analgesia to an animal is provided.
[0119] In certain embodiments, methods for treating schizophrenia
are provided. For example, paranoid type schizophrenia,
disorganized type schizophrenia (i.e., hebephrenic schizophrenia),
catatonic type schizophrenia, undifferentiated type schizophrenia,
residual type schizophrenia, post-schizophrenic depression, and
simple schizophrenia may be treated using the methods and
compositions contemplated herein. Psychotic disorders such as
schizoaffective disorders, delusional disorders, brief psychotic
disorders, shared psychotic disorders, and psychotic disorders with
delusions or hallucinations may also be treated using the
compositions contemplated herein.
[0120] Paranoid schizophrenia may be characterized where delusions
or auditory hallucinations are present, but thought disorder,
disorganized behavior, or affective flattening are not. Delusions
may be persecutory and/or grandiose, but in addition to these,
other themes such as jealousy, religiosity, or somatization may
also be present.
[0121] Disorganized type schizophrenia may be characterized where
thought disorder and flat affect are present together.
[0122] Catatonic type schizophrenia may be characterized where the
subject may be almost immobile or exhibit agitated, purposeless
movement. Symptoms can include catatonic stupor and waxy
flexibility.
[0123] Undifferentiated type schizophrenia may be characterized
where psychotic symptoms are present but the criteria for paranoid,
disorganized, or catatonic types have not been met.
[0124] Residual type schizophrenia may be characterized where
positive symptoms are present at a low intensity only.
[0125] Post-schizophrenic depression may be characterized where a
depressive episode arises in the aftermath of a schizophrenic
illness where some low-level schizophrenic symptoms may still be
present.
[0126] Simple schizophrenia may be characterized by insidious and
progressive development of prominent negative symptoms with no
history of psychotic episodes.
[0127] In some embodiments, methods are provided for treating
psychotic symptoms that may be present in other mental disorders,
including, but not limited to, bipolar disorder, borderline
personality disorder, drug intoxication, and drug-induced
psychosis.
[0128] In another embodiment, methods for treating delusions (e.g.,
"non-bizarre") that may be present in, for example, delusional
disorder are provided.
[0129] Also provided are methods for treating social withdrawal in
conditions including, but not limited to, social anxiety disorder,
avoidant personality disorder, and schizotypal personality
disorder.
[0130] Additionally, methods are provided for treating
obsessive-compulsive disorder (OCD).
EXAMPLES
[0131] The following examples are provided for illustrative
purposes only, and are not intended to limit the scope of the
disclosure.
General Methods
[0132] All solvents used were of laboratory grade solvents.
Tetrahydrofuran was predistilled over KOH and then distilled over
Na/benzophenone under argon. Dichloromethane was distilled over
CaH2. Diisopropyl amine was distilled over KOH.
[0133] Column chromatography was conducted on silica gel 100-200
mesh. For TLC purpose commercially available aluminum backed plates
coated with silica gel 60 F254 from Merck, Darmstadt, West Germany
were used.
[0134] NMR spectra were recorded on a Varian-Unity Inova 500 MHz,
and Bruker Avance III 400 MHz instruments. All NMR spectra were
determined in deuterated DMSO and chemical shifts are reported as
.delta. values in ppm with tetramethylsilane was an internal
standard (.delta.=0). Coupling constants (J) are given in Hertz.
Signals in the 1H NMR spectra are characterized as s (singlet), d
(doublet), t (triplet), m (multiplet), and br s (broad
singlet).
[0135] Chemical purities were determined by UPLC on Waters Aquity
system by using either aq.TFA/aq.MeCN or aq.NH4OAc/aq.MeCN with a
PDA detector. Mass were determined on Schimadzu 2010 EV LCMS system
by using either aq.TFA/aq.MeCN or aq.NH4OAc/aq.MeCN with a PDA
detector. Chiral purities were determined by using Chiralpak (IA)
column (250.times.4.6 mm, Sum) on a Agilent-1200 series using
n-hexane: ethanol as mobile phase with PDA detector.
[0136] Optical rotation were determined in chloroform and water in
a 2-mL cell with 50 mm path length on a JASCO P-2000
polarimeter.
Example 1
Synthesis of
(S)--N-((2S,3R)-1-amino-3-hydroxy-1-oxobutan-2-yl)-1-((S)-1-((S)-2-amino--
3-hydroxypropanoyl)pyrrolidine-2-carbonyl)pyrrolidine-2-carboxamide
(Compound A)
[0137] The following reaction sequence was used (Scheme A) to
synthesize
(S)--N-((2S,3R)-1-amino-3-hydroxy-1-oxobutan-2-yl)-1-((S)-1-((S)-2-amino--
3-hydroxypropanoyl)pyrrolidine-2-carbonyl)pyrrolidine-2-carboxamide
##STR00014## ##STR00015##
Synthesis of (S)-tert-butyl
1-((S)-3-acetoxy-2-(benzyloxycarbonylamino)-propanoyl)-pyrrolidine-2-carb-
oxylate (2)
[0138] (S)-3-Acetoxy-2-(benzyloxycarbonylamino)-propanoic acid (1.5
g, 5.33 mmol) was dissolved in CH.sub.2Cl.sub.2 (15 mL).
N-Methylmorpholine (NMM) (0.64 mL, 5.87 mmol) and isobutyl
chloroformate (IBCF) (0.72 mL, 6.12 mmol) were added at -15.degree.
C. and stirred for 30 minutes under inert atmosphere. A mixture of
(S)-tert-butyl pyrrolidine-2-carboxylate (1) (998 mg, 5.87 mmol)
and NMM (0.64 mL, 5.87 mmol) in DMF (5 mL) were added drop wise to
the reaction mixture and stirring was continued for another 3 h at
RT. The reaction mixture was diluted with DCM (200 mL), washed with
water (50 mL), citric acid solution (10 mL) and brine (10 mL). The
separated organic layer was dried over anhydrous Na.sub.2SO.sub.4
and concentrated under reduced pressure. The obtained crude residue
was purified by silica gel column chromatography eluting with 30%
EtOAc/Hexane to afford compound 2 (1.6 g, 69.5%).
[0139] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 7.81-7.76 (d,
J=20.5 Hz, 1H), 7.35-7.30 (m, 5H), 5.03-4.97 (m, 2H), 4.61-4.55 (m,
1H), 4.32-4.16 (m, 2H), 4.08-3.87 (m, 2H), 3.65-3.59 (m, 1H),
2.21-2.11 (m, 2H), 1.98 (s, 3H), 1.91-1.75 (m, 2H), 1.37 (s,
9H).
[0140] Mass m/z: 435.0 [M.sup.++1].
Synthesis of
(S)-1-((S)-3-acetoxy-2-(benzyloxycarbonylamino)-propanoyl)-pyrrolidine-2--
carboxylic acid (3)
[0141] To a solution of compound 2 (1 g, 2.30 mmol) in
CH.sub.2Cl.sub.2 (5 mL) was added 20% TFA-DCM (10 mL) and stirred
at RT for 2 h. The reaction mixture was diluted with water (10 mL)
and extracted with EtOAc (2.times.15 mL). The organic layer was
dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure to yield compound 3 (800 mg, 92%).
[0142] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 12.58 (br s,
1H), 7.81-7.77 (d, J=8.0 Hz, 1H), 7.35-7.27 (m, 5H), 5.04-4.96 (m,
2H), 4.66-4.60 (m, 1H), 4.32-4.24 (m, 2H), 4.04-3.86 (m, 1H),
3.66-3.59 (t, J=12.6 Hz, 2H), 2.17-2.07 (m, 3H), 1.98-1.80 (m,
4H).
[0143] Mass m/z: 379.0 [M.sup.++1].
Synthesis of (2S,3R)-methyl
2-((S)-1-((S)-1-((R)-3-acetoxy-2-(benzyloxycarbonylamino)-propanoyl)-pyrr-
olidine-2-carbonyl)pyrrolidine-2-carboxamido)-3-hydroxybutanoate
(5)
[0144] Compound 3 (1.0 g, 2.64 mmol) was dissolved in
CH.sub.2Cl.sub.2 (10 mL), NMM (0.32 g, 3.17 mmol) and IBCF (0.41 g,
3.04 mmol) were added to the reaction mixture at -15.degree. C. and
stirred for 30 minutes under inert atmosphere. A mixture of
(2S,3R)-methyl
3-hydroxy-2-((S)-pyrrolidine-2-carboxamido)-butanoate (4) (0.73 g,
3.17 mmol) and NMM (0.35 mL) in DMF (3 mL) were added drop wise to
the reaction mixture at -15.degree. C. and stirring was continued
for another 3 h at RT. The reaction mixture was diluted with DCM
(200 mL), washed with water (20 mL), citric acid solution
(2.times.20 mL) and brine (2.times.50 mL). The separated organic
layer was dried over anhydrous Na.sub.2SO.sub.4 and concentrated
under reduced pressure. The crude residue obtained was purified by
silica gel column chromatography eluting with 5% CH.sub.3OH/EtOAc
to afford compound (5) (0.29 g, 19%).
[0145] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.83-7.81 (m,
1H), 7.72-7.70 (m, 1H), 7.36-7.35 (m, 5H), 5.07-5.01 (m, 2H),
4.99-4.93 (m, 1H), 4.58 (s, 1H), 4.50-4.48 (m, 1H), 4.26-4.22 (m,
2H), 4.07-4.00 (m, 2H), 3.89-3.86 (m, 1H), 3.61-3.55 (m, 5H), 3.53
(s, 1H), 3.39 (s, 1H), 2.12 (s, 1H), 1.98 (s, 3H), 1.94-1.83 (m,
4H), 1.81-1.80 (m, 3H), 1.05 (d, J=6.5 Hz, 3H).
[0146] Mass m/z: 591.0 [M.sup.+ 1].
Synthesis of
benzyl-(R)-1-((S)-2-((S)-2-((2S,3R)-1-(aminooxy)-3-hydroxy-1-oxobutan-2-y-
lcarbamoyl)-pyrrolidine-1-carbonyl)-pyrrolidin-1-yl)-3-hydroxy-1-oxopropan-
-2-ylcarbamate (6)
[0147] A solution of methanolic ammonia (3 mL) was added to
compound 5 (0.28 g, 0.47 mmol) and stirred at RT for 18 h. The
volatiles were evaporated under reduced pressure to afford compound
6 (0.21 g, 82.3%).
[0148] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.38-7.31 (m,
5H), 7.26 (s, 1H), 7.10-7.03 (m, 2H), 6.65 (br s, 1H), 5.04-5.01
(m, 2H), 4.98-4.84 (m, 1H), 4.76-4.75 (m, 1H), 4.61 (s, 1H),
4.38-4.31 (m, 2H), 4.02-4.00 (m, 2H), 3.77-3.74 (m, 1H), 3.67-3.56
(m, 3H), 3.44-3.37 (m, 2H), 2.14-1.86 (m, 8H), 1.01-1.00 (m,
3H).
[0149] Mass m/z: 550 [M.sup.++1].
Synthesis of
(S)--N-((2S,3R)-1-amino-3-hydroxy-1-oxobutan-2-yl)-1-((S)-1-((S)-2-amino--
3-hydroxypropanoyl)-pyrrolidine-2-carbonyl)-pyrrolidine-2-carboxamide
(Compound A)
[0150] To a solution of compound 6 (0.21 g, 0.39 mmol) in methanol
(5 mL) was added 10% Pd/C (30 mg) and the reaction mixture was
stirred under hydrogen atmosphere for 2 h. The reaction mixture was
filtered over celite, solvent was evaporated in vacuo, and the
crude residue obtained was triturated with diethyl ether to yield A
(130 mg, 83.3%).
[0151] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6) (Rotamers): .delta.
7.39 (d, J=8.0 Hz, 1H), 7.08-7.03 (m, 2H), 6.65 (br s, 1H),
4.89-4.85 (m, 1H), 1.61-1.59 (m, 1H), 4.39-4.38 (m, 1H), 4.02-4.00
(m, 2H), 3.68-3.52 (m, 4H), 3.43-3.36 (m, 2H), 3.22-3.10 (m, 2H),
2.19-2.13 (m, 1H), 2.07-1.98 (m, 1H), 1.93-1.81 (m, 5H), 1.75 (s,
2H), 1.01-1.00 (m, 3H).
[0152] LCMS m/z: 400.2 [M.sup.++1].
[0153] HPLC Purity: 99.27%.
Synthesis of (S)-1-(benzyloxycarbonyl) pyrrolidine-2-carboxylic
acid (8)
[0154] To a stirred solution of (S)-pyrrolidine-2-carboxylic acid
(7) (2.0 g, 17.39 mmol) in THF: H.sub.2O (20 mL, 1:1) were added
Na.sub.2CO.sub.3 (2.76 g, 26.08 mmol) and Cbz-Cl (3.54 g, 20.80
mmol) and stirred at RT for 18 h. The reaction mixture was washed
with EtOAc (10 mL) and the aqueous layer was acidified with 3N HCl
and extracted with EtOAc (2.times.20 mL). The combined organic
layer was washed with brine, dried over anhydrous Na.sub.2SO.sub.4
and concentrated under reduced pressure to yield compound 8 (3.0 g,
69.7%).
[0155] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 12.62 (br s,
1H), 7.36-7.22 (m, 5H), 5.12-5.00 (m, 2H), 4.24-4.15 (dd, J=5.0,
36.0 Hz, 1H), 3.46-3.31 (m, 2H), 2.25-2.15 (m, 1H), 1.94-1.79 (m,
3H).
[0156] Mass m/z: 250.0 [M.sup.++1].
Synthesis of (S)-benzyl 2-((2S,
3R)-3-hydroxy-1-methoxy-1-oxobutan-2-ylcarbamoyl)pyrrolidine-1-carboxylat-
e (9)
[0157] Compound 8 (5.0 g, 20.08 mmol) was dissolved in
CH.sub.2Cl.sub.2 (50 mL), NMM (2.43 mL, 22.08 mmol) and IBCF (2.74
mL, 23.09 mmol) were added and stirred at -15.degree. C. for 30
minutes under inert atmosphere. A mixture of (2S,3R)-methyl
2-amino-3-hydroxybutanoate (2.93 g, 22.08 mmol) and NMM (2.43 mL,
22.08 mmol) in DMF (15 mL) were added drop wise at -15.degree. C.
The resultant reaction mixture was stirred at RT for 3 h. It was
diluted with DCM (200 mL) and the organic layer was washed with
water (50 mL), brine (50 mL), dried over anhydrous Na.sub.2SO.sub.4
and concentrated under reduced pressure. The obtained crude was
purified by silica gel column chromatography eluting with 30%
EtOAc/Hexane to afford compound 9 (3.1 g, 42%).
[0158] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6)(Rotamers): .delta.
7.98-7.94 (m, 1H), 7.35-7.27 (m, 5H), 5.09-4.94 (m, 3H), 4.44 (dd,
J=5.5, 8.5 Hz, 1H), 4.29-4.27 (m, 1H), 4.12 (s, 1H), 3.62 (s, 3H),
3.44-3.30 (m, 2H), 2.20-2.08 (m, 1H), 1.87-1.78 (m, 3H), 1.08-0.94
(2d, 3H).
[0159] Mass m/z: 365.0 [M.sup.++1].
Example 2
Synthesis of
(S)--N--((S)-1-amino-3-hydroxy-1-oxopropan-2-yl)-1-((S)-1-((2S,3R)-2-amin-
o-3-hydroxybutanoyl) pyrrolidine-2-carbonyl)
pyrrolidine-2-carboxamide (Compound B)
[0160] The following reaction sequence was used (Scheme B) to
synthesize
(S)--N--((S)-1-amino-3-hydroxy-1-oxopropan-2-yl)-1-((S)-1-((2S,3R)-2-amin-
o-3-hydroxybutanoyl) pyrrolidine-2-carbonyl)
pyrrolidine-2-carboxamide:
##STR00016##
Synthesis of (S)-1-(tert-butoxycarbonyl)-pyrrolidine-2-carboxylic
acid (2)
[0161] To an ice cold stirred solution of
(S)-pyrrolidine-2-carboxylic acid (1) (3.0 g, 26.08 mmol) in
THF:H.sub.2O (60 mL, 1:1) were added Na.sub.2CO.sub.3 (5.52 g,
52.16 mmol), Boc.sub.2O (6.25 g, 26.69 mmol) and stirred at RT for
16 h. The reaction mixture was diluted with water and washed with
EtOAc (50 mL). The aqueous layer was acidified with 2N HCl and
extracted with EtOAc (2.times.100 mL). The combined organic layer
was dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure to yield the
(S)-1-(tert-butoxycarbonyl)-pyrrolidine-2-carboxylic acid (2) (4.8
g, 86%).
[0162] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 12.49 (br s,
1H), 4.08-4.03 (m, 1H), 3.36-3.24 (m, 2H), 2.22-2.11 (m, 1H),
1.87-1.76 (m, 3H), 1.39 (s, 9H).
[0163] Mass m/z: 216.0 [M.sup.++1].
Synthesis of (S)-tert-butyl
2-((S)-3-hydroxy-1-methoxy-1-oxopropan-2-ylcarbamoyl)-pyrrolidine-1-carbo-
xylate (3)
[0164] Compound 2 (2.0 g, 9.00 mmol) was dissolved in
CH.sub.2Cl.sub.2 (10 mL) cooled to -15.degree. C., NMM (1.12 mL,
10.2 mmol) and IBCF (1.26 mL, 1.15 mmol) were added and stirred at
0.degree. C. for 20 minutes. A mixture of (S)-methyl
2-amino-3-hydroxypropanoate (1.59 g, 10.2 mmol) and NMM (1.12 mL)
in DMF (3 mL) were added drop wise at -15.degree. C. and the
resultant reaction mixture was stirred at RT for 1 h. It was
diluted with DCM (200 mL), water (50 mL) and washed with 2N HCl (20
mL) and brine (2.times.50 mL). The separated organic layer was
dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure. The crude residue obtained was purified by silica
gel column chromatography eluting with 20% EtOAc/Hexane to afford
compound 3 (2.3 g) as a syrup.
[0165] Mass m/z: 317.0 [M.sup.++1].
Synthesis of (S)-methyl 3-hydroxy-2-((S)-pyrrolidine-2-carboxamido)
propionate (4)
[0166]
(S)-Tert-butyl-2-((S)-3-hydroxy-1-methoxy-1-oxopropan-2-ylcarbamoyl-
)-pyrrolidine-1-carboxylate (3) (500 mg, 1.58 mmol) was dissolved
in 1,4-dioxane (3 mL) and a HCl solution in dioxane (3.16 mL, 3.16
mmol) was added stirred at RT for 4 h. The volatiles were
evaporated under reduced pressure to afford compound 4 (280 mg) as
solid.
[0167] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 9.99 (br s,
1H), 9.12-9.08 (m, 1H), 8.53 (br s, 1H), 5.48 (br s, 2H), 4.43-4.22
(m, 2H), 3.82-3.67 (m, 4H), 3.56 (s, 3H), 2.36-2.27 (m, 1H),
1.93-1.86 (m, 3H).
[0168] Mass m/z: 217.0 [M.sup.++1].
Synthesis of (S)-methyl 2-((S)-1-((S)-1-((2R,
3S)-3-acetoxy-2-(benzyloxycarbonylamino)-butanoyl)-pyrrolidine-2-carbonyl-
)-pyrrolidine-2-carboxamido)-3-hydroxypropanoate (6)
[0169]
(2S)-1-((2R)-3-acetoxy-2-(benzyloxycarbonylamino)-butanoyl)-pyrroli-
dine-2-carboxylic acid (5) (1.3 g, 2.62 mmol) was dissolved in
CH.sub.2Cl.sub.2 (15 mL), NMM (0.43 mL) and IBCF (0.51 mL) was
added at -10.degree. C. and stirred for 30 minutes under inert
atmosphere. A mixture of
(S)-methyl-3-hydroxy-2-((S)-pyrrolidine-2-carboxamido)-propionate
(4) (992 mg, 3.93 mmol) and NMM (0.43 mL) in DMF (5 mL) were added
drop wise to the reaction mixture and stirring was continued for
another 3 h at RT. The reaction mixture was diluted with DCM (200
mL), washed with water (20 mL), citric acid solution (2.times.20
mL) and brine (2.times.50 mL). The separated organic layer was
dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure. The obtained crude material was purified by
silica gel column chromatography eluting with 5%
CH.sub.3OH/CH.sub.2Cl.sub.2 to afford compound 6 (270 mg,
17.5%).
[0170] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 8.13 (d, J=8.0
Hz, 1H), 7.74 (d, J=7.5 Hz, 1H), 7.38-7.31 (m, 5H), 5.08-4.96 (m,
3H), 4.85-4.82 (m, 1H), 4.56 (d, J=8.0 Hz, 1H), 4.44-4.42 (m, 2H),
4.27 (d, J=7.0 Hz, 1H), 4.10 (d, J=10.5 Hz, 2H), 3.81-3.78 (m, 1H),
3.72-3.70 (m, 1H), 3.61-3.59 (m, 3H), 3.54-3.50 (m, 2H), 2.16-2.14
(m, 1H), 2.05-2.01 (m, 1H), 1.90 (s, 3H), 1.87-1.86 (m, 3H),
1.85-1.84 (m, 3H), 1.21-1.20 (d, J=6.0 Hz, 3H).
[0171] Mass m/z: 591.0 [M.sup.++1].
Synthesis of
Benzyl-(2R,3S)-1-((S)-2-((S)-2-((S)-1-(aminooxy)-3-hydroxy-1-oxopropan-2--
ylcarbamoyl)
pyrrolidine-1-carbonyl)pyrrolidin-1-yl)-3-hydroxy-1-oxobutan-2-ylcarbamat-
e (7)
[0172] To a solution of compound 6 (250 g, 0.42 mmol) in CH.sub.3OH
(2 mL) was added MeOH--NH.sub.3 (10 mL) and was stirred at RT for
16 h. The volatiles were evaporated under reduced pressure to
afford compound 7 (190 mg, 84%).
[0173] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.60 (d, J=7.5
Hz, 1H), 7.35-7.30 (m, 5H), 7.18 (d, J=7.0 Hz, 1H), 7.11-7.06 (m,
2H), 5.05-4.97 (m, 2H), 4.82-4.81 (m, 1H), 4.60-4.59 (m, 2H),
4.33-4.31 (m, 1H), 4.15-4.08 (m, 2H), 3.81-3.79 (m, 1H), 3.72-3.64
(m, 2H), 3.59-3.53 (m, 4H), 2.14 (s, 1H), 2.03 (d, J=9.0 Hz, 1H),
1.95-1.85 (m, 5H), 1.75 (s, 1H), 1.10 (d, J=6.5 Hz, 3H).
[0174] Mass m/z: 550.0 [M.sup.++1].
Synthesis of
(S)--N--((S)-1-amino-3-hydroxy-1-oxopropan-2-yl)-1-((S)-1-((2S,3R)-2-amin-
o-3-hydroxybutanoyl)
pyrrolidine-2-carbonyl)-pyrrolidine-2-carboxamide (B)
[0175] To a solution of compound 7 (190 mg, 0.35 mmol) in methanol
(5 mL) was added 10% Pd/C (50 mg) and the reaction mixture was
stirred under hydrogen atmosphere for 2 h. The reaction mixture was
filtered through a celite pad, solvent was evaporated in vacuo and
the crude was purified by column chromatography on basic alumina
using 0-5% CH.sub.3OH in CH.sub.2Cl.sub.2 as eluent to yield
compound B (130 mg, 73%).
[0176] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.65-7.60 (m,
1H), 7.12-7.03 (m, 2H), 4.81 (br s, 1H), 4.58-4.57 (m, 1H), 4.49
(m, 1H), 4.38-4.19 (m, 1H), 4.10-4.06 (m, 1H), 3.69-3.62 (m, 2H),
3.59-3.56 (m, 4H), 3.49-3.45 (m, 2H), 3.37-3.26 (m, 2H), 2.19-2.15
(m, 1H), 2.09-1.99 (m, 1H), 1.95-1.84 (m, 5H), 1.75 (s, 1H), 1.06
(d, J=13.0 Hz, 3H).
[0177] LCMS m/z: 400.8 [M.sup.++1].
[0178] HPLC Purity: 97.71%.
Example 3
Synthesis of
(S)--N--((S)-1-amino-3-hydroxy-1-oxopropan-2-yl)-1-((S)-1-((S)-2-amino-3--
hydroxy-propanoyl)-pyrrolidine-2-carbonyl)-pyrrolidine-2-carboxamide
(Compound C)
[0179] The following reaction sequence was used (Scheme C) to
synthesize
(S)--N--((S)-1-amino-3-hydroxy-1-oxopropan-2-yl)-1-((S)-1-((S)-2-amino-3--
hydroxy-propanoyl)-pyrrolidine-2-carbonyl)-pyrrolidine-2-carboxamide
##STR00017##
Synthesis of (S)-1-(tert-butoxycarbonyl)-pyrrolidine-2-carboxylic
acid (2)
[0180] To a stirred solution of (S)-pyrrolidine-2-carboxylic acid
(3.0 g, 26.08 mmol) in THF:H.sub.2O (60 mL, 1:1) at 0.degree. C.
were added Na.sub.2CO.sub.3 (5.52 g, 52.16 mmol) and Boc.sub.2O
(6.25 g, 26.69 mmol) and stirred at RT for 16 h. The reaction
mixture was diluted with water and washed with EtOAc (50 mL). The
aqueous layer was acidified with 2N HCl and extracted with EtOAc
(2.times.50 mL). The combined organic layer was dried over
anhydrous Na.sub.2SO.sub.4 and concentrated under reduced pressure
to yield the (S)-1-(tert-butoxycarbonyl)-pyrrolidine-2-carboxylic
acid 2 (4.8 g, 85.7%).
[0181] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 12.49 (br s,
1H), 4.08-4.03 (m, 1H), 3.36-3.24 (m, 2H), 2.22-2.11 (m, 1H),
1.87-1.76 (m, 3H), 1.39 (s, 9H).
[0182] Mass m/z: 216.0 [M.sup.++1].
Synthesis of (S)-tert-butyl
2-((S)-3-hydroxy-1-methoxy-1-oxopropan-2-ylcarbamoyl)
pyrrolidine-1-carboxylate (3)
[0183] Compound 2 (2.0 g, 9.00 mmol) was dissolved in
CH.sub.2Cl.sub.2 (10 mL) cooled to -15.degree. C., NMM (1.12 mL,
10.2 mmol) and IBCF (1.26 mL, 1.15 mmol) were added and stirred at
0.degree. C. for 20 minutes. A mixture of
(S)-methyl-2-amino-3-hydroxypropanoate (1.59 g, 10.2 mmol) and NMM
(1.12 mL) in DMF (3 mL) were added drop wise at -15.degree. C. The
resultant reaction mixture was stirred at RT for 1 h. The reaction
mixture was diluted with DCM (200 mL) and water (25 mL) and was
washed with 2N HCl (20 mL) and brine (10 mL). The separated organic
layer was dried over anhydrous Na.sub.2SO.sub.4 and concentrated
under reduced pressure. The obtained crude material was purified by
silica gel column chromatography eluting with 20% EtOAc/Hexane to
afford compound 3 (2.3 g) as solid.
[0184] Mass m/z: 317.0 [M.sup.++1].
Synthesis of (S)-methyl 3-hydroxy-2-((S)-pyrrolidine-2-carboxamido)
propanoate (4)
[0185] To a solution of
(S)-tert-butyl-2-((S)-3-hydroxy-1-methoxy-1-oxopropan-2-ylcarbamoyl)
pyrrolidine-1-carboxylate 3 (500 mg, 1.58 mmol) in 1,4-dioxane (3
mL) was added a solution of HCl in dioxane (3.16 mL, 3.16 mmol) and
stirred at RT for 4 h. The volatiles were evaporated under reduced
pressure to afford compound 4 (280 mg) as solid.
[0186] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 9.99 (br s,
1H), 9.12-9.08 (m, 1H), 8.53 (br s, 1H), 5.48 (br s, 2H), 4.43-4.22
(m, 2H), 3.82-3.67 (m, 4H), 3.56 (s, 3H), 2.36-2.27 (m, 1H),
1.93-1.86 (m, 3H).
[0187] Mass m/z: 217.0 [M.sup.++1].
Synthesis of (S)-methyl
2-((S)-1-((S)-1-((S)-2-(benzyloxycarbonylamino)-3-hydroxypropanoyl)-pyrro-
lidine-2-carbonyl)-pyrrolidine-2-carboxamido)-3-hydroxypropanoate
(6)
[0188]
(S)-1-((S)-3-Acetoxy-2-(benzyloxycarbonylamino)-propanoyl)-pyrrolid-
ine-2-carboxylic acid (5) (400 mg, 1.05 mmol) was dissolved in
CH.sub.2Cl.sub.2 (2 mL), NMM (0.13 mL) and IBCF (0.14 mL) were
added at -15.degree. C. and stirred for 30 minutes under inert
atmosphere. A mixture of
(S)-methyl-3-hydroxy-2-((S)-pyrrolidine-2-carboxamido)-propanoate
hydrochloride (4) (293 mg, 1.16 mmol) and NMM (0.13 mL) in DMF (2
mL) were added drop wise to the reaction mixture and stirring was
continued for another 3 h at RT. The reaction mixture was diluted
with DCM (200 mL), washed with water (20 mL) and brine (10 mL). The
separated organic layer was dried over anhydrous Na.sub.2SO.sub.4
and concentrated under reduced pressure. The obtained crude
material was purified by silica gel column chromatography eluting
with 5% CH.sub.3OH/CH.sub.2Cl.sub.2 to afford compound 6 (80 mg,
13%).
[0189] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 8.09 (d, J=7.5
Hz, 1H), 7.71 (d, J=8.0 Hz, 1H), 7.36-7.31 (m, 6H), 5.07-4.99 (m,
3H), 4.59-4.58 (m, 2H), 4.41-4.40 (m, 1H), 4.29-4.24 (m, 3H), 3.86
(t, J=9.5 Hz, 1H), 3.72-3.68 (m, 1H), 3.64-3.57 (m, 3H), 3.40-3.38
(m, 3H), 2.14-2.01 (m, 2H), 1.98 (s, 3H), 1.90-1.80 (m, 6H).
[0190] Mass m/z: 535.0 [M.sup.++1].
Synthesis of
Benzyl-(S)-1-((S)-2-((S)-2-((S)-1-amino-3-hydroxy-1-oxopropan-2-ylcarbamo-
yl) pyrrolidine-1-carbonyl)
pyrrolidin-1-yl)-3-hydroxy-1-oxopropan-2-ylcarbamate (7)
[0191] To a solution of
(S)-methyl-2-((S)-1-((S)-1-((S)-2-(benzyloxycarbonylamino)-3-hydroxypropa-
noyl)-pyrrolidine-2-carbonyl)-pyrrolidine-2-carboxamido)-3-hydroxypropanoa-
te (6) (60 mg, 1.04 mmol) in MeOH was added MeOH--NH.sub.3 (3 mL)
was stirred at RT for 16 h. The volatiles were evaporated under
reduced pressure to afford compound 7 (30 mg, 55%).
[0192] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.60 (d, J=7.5
Hz, 1H), 7.36-7.31 (m, 6H), 7.11-7.06 (m, 2H), 5.04-4.98 (m, 2H),
4.82-4.74 (m, 2H), 4.61-4.59 (m, 1H), 4.36-4.30 (m, 2H), 4.10-4.07
(m, 1H), 3.67-3.65 (m, 2H), 3.59-3.55 (m, 6H), 3.44-3.40 (m, 2H),
1.95-1.92 (m, 6H).
[0193] Mass m/z: 520.0 [M.sup.++1].
Synthesis of
(S)--N--((S)-1-amino-3-hydroxy-1-oxopropan-2-yl)-1-((S)-1-((S)-2-amino-3--
hydroxy-propanoyl)-pyrrolidine-2-carbonyl)-pyrrolidine-2-carboxamide
(C)
[0194]
Benzyl-(S)-1-((S)-2-((S)-2-((S)-1-amino-3-hydroxy-1-oxopropan-2-ylc-
arbamoyl) pyrrolidine-1-carbonyl)
pyrrolidin-1-yl)-3-hydroxy-1-oxopropan-2-ylcarbamate 7 (300 mg,
0.57 mmol) was dissolved in methanol (8 mL), 10% Pd/C (50 mg) was
added and reaction mixture was stirred under hydrogen atmosphere
for 2 h. The reaction mixture was filtered and the filtrate was
concentrated under reduced pressure to yield compound C (150 mg,
68%).
[0195] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6) (Rotamers): .delta.
7.62 (d, J=8.0 Hz, 1H), 7.24 (br s, 1H), 7.14-7.07 (m, 2H),
4.87-4.82 (m, 2H), 4.59-4.57 (m, 1H), 4.37-4.31 (m, 2H), 4.11-4.07
(m, 2H), 3.70-3.39 (m, 8H), 2.17-2.01 (m, 2H), 1.95-1.79 (m,
6H).
[0196] LCMS m/z: 386.4 [M.sup.++1].
[0197] HPLC Purity: 98.45%.
Example 4
Synthesis of
N-((2S,3R)-1-amino-3-hydroxy-1-oxobutan-2-yl)-1-((S)-1-((2S,3R)-2-amino-3-
-hydroxybutanoyl)-pyrrolidine-2-carbonyl)-2-benzylpyrrolidine-2-carboxamid-
e (Compound D & E)
[0198] The following reaction sequence was used (Scheme D) to
synthesize
N-((2S,3R)-1-amino-3-hydroxy-1-oxobutan-2-yl)-1-((S)-1-((2S,3R)-2-amino-3-
-hydroxybutanoyl)-pyrrolidine-2-carbonyl)-2-benzsaylpyrrolidine-2-carboxam-
ide (Compound D & E):
##STR00018## ##STR00019##
Synthesis of 1-Benzyl 2-ethyl 2-benzylpyrrolidine-1,2-dicarboxylate
(2)
[0199] To a solution of (S)-1-benzyl-2-ethyl-pyrrolidine-1,
2-dicarboxylate (1) (10 g, 36.10 mmol) in THF (150 mL) under inert
atmosphere was added LiHMDS (1M in THF) (43.3 mL, 43.3 mmol) at
-25.degree. C. and stirred for 2 h. Benzyl bromide (5.17 mL, 43.26
mmol) was added drop wise at -25.degree. C. to the reaction
mixture. It was allowed to warm to RT and stirred for 2 h. The
reaction mixture was cooled to 5.degree. C., quenched with
saturated NH.sub.4Cl solution and the aqueous layer was extracted
with EtOAc (2.times.200 mL). The combined organic extracts were
dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure. The crude residue obtained was purified by silica
gel column chromatography eluting with 5% EtOAc/hexane to afford
compound 2 (13 g, 75%) as liquid.
[0200] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 7.47-7.32 (m,
5H), 7.27-7.16 (m, 3H), 7.07-7.04 (m, 2H), 5.29-5.06 (m, 2H),
4.16-3.89 (m, 2H), 3.57-3.33 (m, 2H), 3.02-2.78 (m, 2H), 2.13-1.89
(m, 2H), 1.56-1.51 (m, 1H), 1.21-1.04 (m, 3H), 0.93-0.79 (m,
1H).
[0201] Mass m/z: 368.2 [M.sup.++1].
Synthesis of
2-benzyl-1-(benzyloxycarbonyl)-pyrrolidine-2-carboxylic acid
(3)
[0202] To a stirred solution of compound 2 (8.0 g, 21.79 mmol) in
CH.sub.3OH (20 mL) was added 2N aqueous KOH (20 mL) and heated up
to 100.degree. C. and stirred for 16 h. The volatiles were
evaporated under reduced pressure. The residue obtained was diluted
with ice cold water (50 mL) and washed with ether (50 mL). The
aqueous layer was acidified to pH-2 using HCl solution and
extracted with EtOAc (2.times.100 mL). The combined organic layer
was dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure to afford compound 3 (6 g, 81%) as an off white
solid.
[0203] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 12.71 (br s,
1H), 7.40-7.30 (m, 5H), 7.25-7.19 (m, 3H), 7.07-7.00 (m, 2H),
5.27-5.02 (m, 2H), 3.59-3.32 (m, 2H), 3.02-2.83 (m, 2H), 2.13-1.91
(m, 2H), 1.58-1.49 (m, 1H), 0.90-0.77 (m, 1H).
[0204] Mass m/z: 340.1 [M.sup.++1].
Synthesis of
Benzyl-2-benzyl-2-((2S,3R)-3-hydroxy-1-methoxy-1-oxobutan-2-ylcarbamoyl)--
pyrrolidine-1-carboxylate (4)
[0205] To a suspension of compound 3 (1.0 g, 2.94 mmol),
L-threonine methyl ester (471 mg, 3.53 mmol) in DMF (20 mL) was
added HATU (1.12 g, 2.94 mmol) and DIPEA (1.58 mL, 8.84 mmol) at
5.degree. C. The reaction mixture was stirred at RT for 16 h. It
was diluted with EtOAc (150 mL) and washed with water (2.times.30
mL). The organic layer was washed with brine, dried over
Na.sub.2SO.sub.4, concentrated and purified by silica gel column
chromatography 50% EtOAc/Hexane as eluent to yield compound 4 (1.0
g, 74%).
[0206] .sup.1H-NMR: (200 MHz, DMSO-d.sub.6): .delta. 7.62-7.59 (m,
1H), 7.44-7.31 (m, 5H), 7.21-7.18 (m, 3H), 7.06-6.99 (m, 2H),
5.25-5.24 (m, 1H), 5.12-4.94 (m, 2H), 4.30 (s, 1H), 4.15-4.08 (m,
1H), 3.66-3.64 (m, 3H), 3.63-3.49 (m, 2H), 3.14 (s, 1H), 2.89 (s,
1H), 2.09-2.02 (m, 2H), 1.56-1.51 (m, 1H), 1.09-0.98 (m, 4H).
[0207] Mass m/z: 455.1 [M.sup.+ 1], 477.3 [M+Na].
Synthesis of
Benzyl-2-((2S,3R)-3-acetoxy-1-methoxy-1-oxobutan-2-ylcarbamoyl)-2-benzylp-
yrrolidine-1-carboxylate (5)
[0208] Compound 4 (3 g, 6.60 mmol) was dissolved in THF (30 mL),
Et.sub.3N (1.11 mL, 7.92 mmol) and Ac.sub.2O (742 mg, 7.26 mmol)
were added at RT. The reaction mixture was stirred at RT for 2 h.
The volatiles were evaporated under reduced pressure and the
residue obtained was diluted with CH.sub.2Cl.sub.2 and washed with
dilute HCl. The combined organic extracts were dried over
Na.sub.2SO.sub.4 and concentrated under reduced pressure. The crude
residue was purified by column chromatography using 30%
EtOAc/Hexane as eluent to yield compound 5 (2.5 g, 76%).
[0209] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6) (Rotamers): .delta.
8.15-7.71 (m, 1H), 7.42-7.04 (m, 10H), 5.30-5.19 (m, 2H), 5.11-5.09
(m, 1H), 4.99-4.93 (m, 1H), 4.67-4.62 (m, 1H), 3.66-3.64 (m, 3H),
3.55-3.46 (m, 2H), 3.38-3.35 (m, 1H), 2.88-2.69 (m, 1H), 2.17-2.00
(m, 2H), 1.98-1.92 (m, 3H), 1.56-1.46 (m, 1H), 1.23-1.17 (m, 3H),
1.02-0.86 (m, 1H).
[0210] LCMS m/z: 497.4 [M.sup.++1].
Synthesis of (2S,3R)-methyl
3-acetoxy-2-(2-benzylpyrrolidine-2-carboxamido)-butanoate (6)
[0211] To a stirring solution of compound 5 (4 g, 8.06 mmol) in
ethanol (50 mL) was added 10% Pd/C (1.2 g) and the reaction mixture
was stirred under H.sub.2 atmosphere (balloon pressure) for 4 h. It
was filtered through celite pad and the filtrate was concentrated
under reduced pressure to yield compound 6 (2.2 g, 75%).
[0212] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6) (Rotamers): .delta.
8.22-8.17 (m, 1H), 7.24-7.16 (m, 5H), 5.17 (t, J=11.5 Hz, 1H),
4.48-4.42 (m, 1H), 3.60-3.54 (s, 3H), 3.20 (t, J=13.5 Hz, 1H),
3.06-2.97 (m, 1H), 2.82-2.68 (m, 3H), 2.08-2.02 (m, 1H), 1.89 (s,
3H), 1.72-1.51 (m, 3H), 1.10 (2d, 3H).
[0213] LCMS m/z: 363 [M.sup.++1], 385 [M+Na].
Synthesis of (S)-benzyl
2-(2-((2S,3R)-3-acetoxy-1-methoxy-1-oxobutan-2-ylcarbamoyl)-2-benzylpyrro-
lidine-1-carbonyl) pyrrolidine-1-carboxylate (7)
[0214] To a stirred solution of compound 6 (1 g, 2.76 mmol) and
Na.sub.2CO.sub.3 (732 mg, 6.90 mmol) in CH.sub.2Cl.sub.2:H.sub.2O
(20 mL, 1:1) was added a solution of acid chloride [To a solution
of (S)-1-(benzyloxycarbonyl) pyrrolidine-2-carboxylic acid (825 mg,
3.31 mmol) in CH.sub.2Cl.sub.2 (20 mL) was added SOCl.sub.2 (0.60
mL) drop wise at 0.degree. C. and was refluxed for 2 h. The
volatiles were removed under reduced pressure to yield (S)-benzyl
2-(chlorocarbonyl) pyrrolidine-1-carboxylate] in CH.sub.2Cl.sub.2
and the reaction mixture was stirred at RT for 2 h. The volatiles
were evaporated under reduced pressure. The residue was diluted
with CH.sub.2Cl.sub.2 (100 mL), filtered and the filtrate was
concentrated under vacuum. The crude residue was purified by column
chromatography using 60% EtOAc/Hexane as eluent to afford compound
7 (750 mg, 45%).
[0215] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6) (Rotamers): .delta.
7.36-7.23 (m, 8H), 7.15-7.12 (m, 3H), 5.21-5.15 (m, 2H), 5.04-4.92
(m, 1H), 4.57-4.50 (m, 2H), 3.88 (d, J=14.5 Hz, 1H), 3.65 (s, 3H),
3.54-3.46 (m, 3H), 3.21-3.13 (m, 1H), 3.02-2.90 (m, 2H), 2.19-2.02
(m, 4H), 1.97 (s, 3H), 1.89 (s, 1H), 1.77-1.65 (m, 1H), 1.17 (s,
2H), 1.06 (s, 2H).
[0216] Mass m/z: 594.1 [M.sup.++1].
Synthesis of (2S,3R)-methyl
3-acetoxy-2-(2-benzyl-1-((S)-pyrrolidine-2-carbonyl)-pyrrolidine-2-carbox-
amido) butanoate (8)
[0217] To a solution of compound 7 (200 mg, 0.336 mmol) in EtOAc
(15 mL) was added 10% Pd/C (40 mg) was added under inert atmosphere
and stirred for 12 h under H.sub.2 atmosphere (balloon pressure).
The reaction mixture was filtered through celite pad and
concentrated under reduced pressure. The obtained residue was
triturated with ether (10 mL) to afford compound 8 (125 mg, 81%) as
solid.
[0218] .sup.1H-NMR: (500 MHz, CDCl.sub.3) (Rotamers): .delta.
7.88-7.87 (d, 1H, J=8.5), 7.30-7.26 (m, 2H), 7.24-7.21 (m, 1H),
7.13-7.12 (d, 2H, J=7), 5.44-5.43 (m, 1H), 4.76-4.74 (m, 1H),
3.94-3.92 (m, 1H), 3.84-3.81 (m, 1H), 3.75 (s, 3H), 3.50 (m, 1H),
3.26-3.12 (m, 3H), 2.90-2.88 (m, 1H), 2.23-2.15 (m, 4H), 2.04 (s,
3H), 1.87-1.77 (m, 5H), 1.27-1.24 (m, 3H).
[0219] Mass m/z: 460 (M+1).
Synthesis of Benzyl-2-(tert-butoxycarbonylamino)-3-hydroxybutanoate
(10)
[0220] To a solution of
2-(tert-butoxycarbonylamino)-3-hydroxybutanoic acid (3.0 g, 13.69
mmol) in DMF (50 mL) was added K.sub.2CO.sub.3 (3.73 g, 27.39 mmol)
and stirred at RT for 15 min. (Bromomethyl)benzene (2.81 g, 16.43
mmol) was added and stirred at RT for 6 h. The reaction mixture was
diluted with water (50 mL) and extracted with EtOAc (2.times.50
mL). The combined organic layer was washed with brine (50 mL),
dried over anhydrous Na.sub.2SO.sub.4 and concentrated under
reduced pressure. The crude material was purified by silica gel
column chromatography using 20% EtOAc/hexane as eluent to afford
benzyl 2-(tert-butoxycarbonylamino)-3-hydroxybutanoate 10 (2.8 g,
66%).
[0221] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.37-7.30 (m,
5H), 6.60 (d, J=8.5 Hz, 1H), 5.18-5.08 (m, 2H), 4.76 (d, J=7 Hz,
1H), 4.08-4.00 (m, 2H), 1.38 (s, 9H), 1.09 (d, J=6.0 Hz, 3H).
[0222] Mass m/z: 310.0 [M.sup.+ 1], 210 [M.sup.+-De Boc].
Synthesis of
benzyl-3-acetoxy-2-(tert-butoxycarbonylamino)-butanoate (11)
[0223] To a stirred solution of
benzyl-2-(tert-butoxycarbonylamino)-3-hydroxybutanoate (2.8 g, 9.06
mmol) in THF (80 mL) was added Ac.sub.2O (1.1 g, 10.87 mmol),
Et.sub.3N (1.51 mL, 10.87 mmol) and DMAP (280 mg) and stirred at RT
for 15 min. The volatiles were removed under reduced pressure. The
residue obtained was diluted with EtOAc (150 mL) and washed with
cold 0.5N HCl solution (2.times.20 mL). The organic layer was
washed with brine, dried over anhydrous Na.sub.2SO.sub.4 and
concentrated under reduced pressure to afford
3-acetoxy-2-(tert-butoxycarbonylamino)-butanoate 11 (2.8 g,
88%).
[0224] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 7.35-7.34 (m,
5H), 7.27-7.25 (d, J=8.5 Hz, 1H), 5.18-5.06 (m, 3H), 4.34-4.32 (m,
1H), 1.90 (s, 3H), 1.39 (s, 9H), 1.16 (d, J=3 Hz, 3H).
[0225] Mass m/z: 252 [M.sup.++1-De Boc].
Synthesis of
(2S,3R)-3-acetoxy-2-(tert-butoxycarbonylamino)-butanoic acid
(12)
[0226] Benzyl-3-acetoxy-2-(tert-butoxycarbonylamino) butanoate 11
(1.4 g, 3.98 mmol) was dissolved in EtOAc (40 mL), 10% Pd/C (600
mg) was added and reaction mixture was stirred under hydrogen
atmosphere for 16 h. The reaction mixture was filtered over celite,
solvent was evaporated in vacuo and the crude residue was
triturated with hexane to yield
(2S,3R)-3-acetoxy-2-(tert-butoxycarbonylamino) butanoic acid 12
(0.7 g, 70%).
[0227] .sup.1H-NMR: (500 MHz, DMSO-d.sub.6): .delta. 12.78 (br s,
1H), 6.94 (d, J=9.5 Hz, 1H), 5.16-5.14 (m, 1H), 4.17-4.15 (m, 1H),
1.95 (s, 3H), 1.39 (s, 9H), 1.10 (d, J=6.0 Hz, 3H).
[0228] Mass m/z: 260.0 [M-1].
Synthesis of
(2S,3R)-methyl-3-acetoxy-2-(1-((S)-1-((2S,3R)-3-acetoxy-2-(tert-butoxycar-
bonyl-amino)-butanoyl)-pyrrolidine-2-carbonyl)-2-benzylpyrrolidine-2-carbo-
xamido)-butanoate (13)
[0229] To a solution of compound (2S,
3R)-3-acetoxy-2-(tert-butoxycarbonylamino)-butanoic acid 12 (199
mg, 0.76 mmol) in CH.sub.2Cl.sub.2 (6 mL) was under inert
atmosphere were added IBCF (125 mg, 0.91 mmol) and NMM (154 mg,
1.52 mmol) at -15.degree. C. and stirred for 1 h. A solution of
(2S,3R)-methyl 3-acetoxy-2-(2-benzyl-1-((S)-pyrrolidine-2-carbonyl)
pyrrolidine-2-carboxamido)-butanoate 8 (350 mg, 0.76 mmol) in DMF
(2 mL) was added to the reaction mixture and stirred for 1 h at
-15.degree. C. The resultant reaction mixture was allowed to warm
to RT and stirred for 19 h. The reaction mixture was extracted with
EtOAc and the separated organic layer was washed with water (20
mL), followed by brine (20 mL), dried over Na.sub.2SO.sub.4 and
concentrated under reduced pressure. The crude material was
purified by preparative HPLC to afford compound 13 (100 mg,
20%).
[0230] .sup.1H-NMR: (500 MHz, CD.sub.3OD) (Rotamers): .delta.
7.30-7.24 (m, 3H), 7.15-7.13 (m, 2H), 4.62-4.55 (m, 2H), 4.29-3.97
(m, 1H), 3.98-3.79 (m, 4H), 3.75 (s, 3H), 3.62-3.22 (m, 2H), 3.23
(d, J=13.5 Hz, 1H), 3.00-2.95 (q, 1H), 2.37-2.31 (m, 1H), 2.23-2.10
(m, 2H), 2.02-1.88 (m, 3H), 1.46-1.28 (m, 2H), 0.97 (d, J=7.0 Hz,
6H).
Synthesis of
N-((2S,3R)-1-amino-3-hydroxy-1-oxobutan-2-yl)-1-((S)-1-((2S,3R)-2-amino-3-
-hydroxybutanoyl)-pyrrolidine-2-carbonyl)-2-benzylpyrrolidine-2-carboxamid-
e (D & E)
[0231] A solution of compound 13 (100 mg, 0.153 mmol) in
methanolic-NH.sub.3 (10 mL) was stirred in a sealed tube at RT for
72 h. The reaction mixture was concentrated under reduced pressure.
The obtained crude residue was washed with ether (2.times.2 mL) to
afford a diastereomeric mixture of Compound D & E (85 mg). 85
mg of this mixture was further purified by chiral preparative HPLC
to yield 15 mg each of Compound D and E.
[0232] .sup.1H-NMR: (500 MHz, CD.sub.3OD) (Rotamers): .delta.
7.33-7.26 (m, 3H), 7.16 (s, 2H), 4.55-4.54 (m, 1H), 4.39 (s, 1H),
4.14 (s, 1H), 4.01-3.98 (m, 1H), 3.91-3.71 (m, 3H), 3.59 (s, 2H),
3.25-3.16 (m, 1H), 3.04-3.00 (m, 1H), 2.33-2.10 (m, 3H), 2.01-1.91
(m, 2H), 1.86-1.80 (m, 1H), 1.46-1.44 (m, 1H), 1.34-1.29 (m, 1H),
1.25-1.19 (m, 3H), 0.99-0.97 (d, J=14.0 Hz, 3H).
[0233] Mass m/z: 503 [M.sup.+].
[0234] HPLC Purity: 98.1%.
Example 5
[.sup.3H] MK-801 Binding Assay
[0235] This example demonstrates a [.sup.3H] MK-801 binding assay
that may be used to assess agonistic and/or antagonistic properties
of candidate NMDA receptor modulators.
[0236] Crude synaptic membranes were prepared from rat forebrains
as described in Moskal et al. (2001), "The use of antibody
engineering to create novel drugs that target N-methyl-D-aspartate
receptors," Curr. Drug Targets, 2:331-45. Male 2-3 month old rats
were decapitated without anesthesia by guillotine, and the brains
were rapidly removed (.about.90 sec) and whole cortex and
hippocampus dissected on an ice cold platform, frozen on dry ice,
and stored at -80.degree. C. Samples were homogenized in 20 volumes
of ice cold 5 mM Tris-HCl pH 7.4 by Brinkman Polytron and pelleted
48,000.times.g for 20 min at 4.degree. C., and washed an additional
3 times as described above. Membranes were then resuspended in 5 mM
EDTA and 15 mM Tris-HCl pH 7.4 and incubated for 1 hr at 37.degree.
C., membranes pelleted at 48,000.times.g for 20 min at 4.degree.
C., snap frozen in liquid nitrogen, and stored at -80.degree. C. On
the day of the experiment, membranes were thawed at room
temperature and washed an additional 7 times in ice cold 5 mM
Tris-HCl (pH 7.4) as described above. After the last wash,
membranes were resuspended in assay buffer (5 mM Tris-acetate pH
7.4), and protein content was determined by the BCA assay.
[0237] [.sup.3H] MK-801 binding assays were preformed as described
in Urwyler et al. (2009), "Drug design, in vitro pharmacology, and
structure-activity relationships of 3-acylamino-2-aminopropionic
acid derivatives, a novel class of partial agonists at the glycine
site on the N-methyl-D-aspartate (NMDA) receptor complex," J. Med.
Chem., 52:5093-10. Membrane protein (200 .mu.g) was incubated with
varying concentrations of the test compounds
(10.sup.-3-10.sup.-17M) with 50 .mu.M glutamate for 15 min at
23.degree. C. Assay tubes were then incubated under non-equilibrium
conditions with [.sup.3H]MK-801 (5 nM; 22.5 Ci/mmol) for 15 min at
23.degree. C. followed by filtration through Whatman GF/B filters
using a Brandel M-24R Cell Harvester. Then the tubes were washed
three times with assay buffer (5 mM Tris-acetate PH 7.4), and the
filters were analyzed by liquid scintillation to calculate the
disintegrations per minute (DPM). Zero levels were determined in
the absence of any glycine ligand and in the presence of 30 .mu.M
5,7-Dichlorokynurenic acid (5,7-DCKA). Maximal stimulation was
measured in the presence of 1 mM glycine. 50 .mu.M glutamate was
present in all samples.
[0238] For each data point (i.e., a single concentration of the
test compound), the % maximal [.sup.3H] MK-801 binding was
calculated by the following formula:
% maximal [.sup.3H]MK-801 binding=((DPM.sub.(test
compound)-DPM.sub.5,7-DCKA)/(DPM.sub.1 mM
glycine-DPM.sub.5,7-DCKA)).times.100%
[0239] The efficacy for each compound, expressed as the % increase
in [.sup.3H] MK-801 binding, is calculated by fitting the data to a
"log(agonist) vs. response (three parameters)" equation using Graph
Pad Prism, with the efficacy for the test compound being the
best-fit top value.
TABLE-US-00001 TABLE 1 [.sup.3H] MK-801 Binding Assay Data.
Efficacy (% Increase in Compound Potency [.sup.3H] MK-801 Binding)
A 5 pM 79% B 6 pM 24% C 16 pM 23% D 0.2 pM 12% E 0.2 pM 12%
Example 6
NMDA Receptor (NMDAR) Currents
[0240] This example demonstrates an assay for determining the
effect of test compounds on NMDAR currents.
[0241] Experiments were conducted on hippocampal slices from 14-18
day old Sprague-Dawley rats as described in Zhang et al. (2008) "A
NMDA receptor glycine site partial agonist, GLYX-13, simultaneously
enhances LTP and reduces LTD at Schaffer collateral-CA1 synapses in
hippocampus," Neuropharmacology, 55:1238-50. Whole cell recordings
were obtained from CA1 pyramidal neurons voltage clamped at 60 mV,
in slices perfused with (artificial cerebrospinal fluid) ACSF
containing 0 mM [Mg2+] and 3 mM [Ca2+], plus 10 .mu.M bicuculline
and 20 .mu.M CNQX to pharmacologically isolate NMDAR-dependent
excitatory postsynaptic currents (EPSCs). Varying concentrations of
test compound (10 nM to 1 .mu.M) were bath applied and Schaffer
collateral fibers were stimulated with single electrical pulses (80
.mu.s duration) once every 30 s. NMDAR EPSCs were characterized by
long rise and decay times, and were fully blocked at the end of
each experiment by bath application of the NMDAR-specific
antagonist D-2-amino-5-phosphonopentanoic acid (D-AP5; 50 .mu.M).
The efficacy of a test compound was calculated as the % increased
in NMDAR current from the baseline. The baseline was measured as
the NMDAR current before the test compound was applied.
TABLE-US-00002 TABLE 2 NMDAR Current Assay Data. Efficacy (% Change
in Compound Concentration NMDAR Current from Baseline) A 1 .mu.M
70% B NT NT C NT NT D 1 .mu.M 75% E 1 .mu.M 10% NT = not
tested.
Example 7
Long-Term Potentiation (LTP) Assay
[0242] This example demonstrates an assay for determining the
effect of test compounds on LTP.
[0243] Hippocampal slices from 14-18 day old Sprague-Dawley rats
were transferred to an interface recording chamber and continuously
perfused at 3 ml/min with oxygenated ACSF at 32.+-.0.5.degree. C.
Low resistance recording electrodes were made from thin-walled
borosilicate glass (1-2 MQ after filling with ACSF) and inserted
into the apical dendritic region of the Schaffer collateral
termination field in stratum radiatum of the CA1 region to record
field excitatory postsynaptic potentials (fEPSPs). A bipolar
stainless steel stimulating electrode (FHC Co.) was placed on
Schaffer collateral-commissural fibers in CA3 stratum radiatum, and
constant current stimulus intensity adjusted to evoke approximately
half-maximal fEPSPs once each 30 s (50-100 pA; 100 ms duration).
fEPSP slope was measured by linear interpolation from 20%-80% of
maximum negative deflection, and slopes confirmed to be stable to
within .+-.10% for at least 10 min before commencing an experiment.
Long-term potentiation (LTP) was induced by a high frequency
stimulus train (3.times.100 Hz/500 ms; arrow) at Schaffer
collateral-CA1 synapses in control (vehicle), untreated slices, or
slices pre-treated with test compound (10 nM to 100 .mu.M).
Long-term potentiation signals were recorded using a Multiclamp
700B amplifier and digitized with a Digidata 1322 (Axon
Instruments, Foster City, Calif.). Data were analyzed using pClamp
software (version 9, Axon Instruments) on an IBM-compatible
personal computer. The efficacy was calculated as the % increase in
long-term potentiation measured for slices pre-treated with test
compound as compared to vehicle.
TABLE-US-00003 TABLE 3 LTP Assay Data. Efficacy (% Increase
Compound Concentration from Vehicle) A NT NT B NT NT C NT NT D 1 uM
30% E 1 uM 10% NT = not tested.
Example 8
Porsolt Test
[0244] This example demonstrates the Porsolt test for assessing
test compounds for antidepressant activity.
[0245] Experiments were conducted as described in Burgdorf et al.
(2009) "The effect of selective breeding for differential rates of
50-kHz ultrasonic vocalizations on emotional behavior in rats,"
Devel. Psychobiol., 51:34-46. Male Sprague-Dawley rats (2-3 month
old) were dosed with test compound (0.3 to 30 mg/kg; intravenously
via tail vein injection, or per os via gastric gavage) or vehicle
(1 ml/kg sterile saline, or 1 ml/kg DMSO for
2,5-diazaspiro[3.4]octan-1-one) in a blind manner 1 hr before
testing. Animals were placed in a 46 cm tall.times.20 cm in
diameter clear glass tube filled to 30 cm with tap water at room
temperature (23.degree. C..+-.0.5.degree. C.) for 5 min on the test
day. All animals were towel dried after each swimming session by
the experimenter. Water was changed after every other animal.
Animals were videotaped and total duration (sec) of floating
behavior (as defined as the minimal movement required in order to
maintain the animal's head above the water) was quantified by a
blind experimenter.
TABLE-US-00004 TABLE 4 Porsolt Assay Data. Compound Dose, Route %
Reduction in Floating A 3 mg/kg, i.v..sup. 90% B NT NT C NT NT D 1
mg/kg, p.o. 84% E 1 mg/kg, p.o. 63% NT = not tested.
EQUIVALENTS
[0246] Those skilled in the art will recognize, or be able to
ascertain using no more than routine experimentation, many
equivalents to the specific embodiments of the invention described
herein. Such equivalents are intended to be encompassed by the
following claims.
INCORPORATION BY REFERENCE
[0247] The entire contents of all patents, published patent
applications, websites, and other references cited herein are
hereby expressly incorporated herein in their entireties by
reference.
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