U.S. patent application number 13/155827 was filed with the patent office on 2012-02-02 for morphinan compounds.
Invention is credited to Philip B. Graham, I. Robert Silverman.
Application Number | 20120029007 13/155827 |
Document ID | / |
Family ID | 41213342 |
Filed Date | 2012-02-02 |
United States Patent
Application |
20120029007 |
Kind Code |
A1 |
Graham; Philip B. ; et
al. |
February 2, 2012 |
MORPHINAN COMPOUNDS
Abstract
This invention relates to novel morphinan compounds and
pharmaceutically acceptable salts thereof. This invention also
provides compositions comprising a compound of this invention and
the use of such compositions in methods of treating diseases and
conditions that are beneficially treated by administering a
.sigma..sub.1 receptor agonist that also has NMDA antagonist
activity.
Inventors: |
Graham; Philip B.;
(Carlisle, MA) ; Silverman; I. Robert; (Arlington,
MA) |
Family ID: |
41213342 |
Appl. No.: |
13/155827 |
Filed: |
June 8, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13119905 |
Jul 1, 2011 |
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PCT/US2009/057476 |
Sep 18, 2009 |
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13155827 |
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61098511 |
Sep 19, 2008 |
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Current U.S.
Class: |
514/282 ;
514/289; 546/74 |
Current CPC
Class: |
C07D 221/28 20130101;
A61K 31/195 20130101; C07D 471/08 20130101; A61P 25/08 20180101;
A61K 31/4709 20130101; A61K 45/06 20130101; A61K 31/485 20130101;
C07B 59/002 20130101; A61P 29/00 20180101; A61P 25/16 20180101 |
Class at
Publication: |
514/282 ; 546/74;
514/289 |
International
Class: |
A61K 31/485 20060101
A61K031/485; A61P 25/00 20060101 A61P025/00; A61P 25/28 20060101
A61P025/28; A61P 9/00 20060101 A61P009/00; A61P 27/06 20060101
A61P027/06; A61P 25/14 20060101 A61P025/14; A61P 35/00 20060101
A61P035/00; A61P 29/00 20060101 A61P029/00; A61P 3/10 20060101
A61P003/10; A61P 27/02 20060101 A61P027/02; A61P 25/08 20060101
A61P025/08; A61P 15/00 20060101 A61P015/00; A61P 11/14 20060101
A61P011/14; A61P 17/00 20060101 A61P017/00; A61P 25/30 20060101
A61P025/30; C07D 221/28 20060101 C07D221/28 |
Claims
1. A compound of Formula I: ##STR00019## or a pharmaceutically
acceptable salt thereof, wherein: R.sup.1 is selected from
--O--(C.sub.2-C.sub.4)alkyl and --(C.sub.1-C.sub.4)alkyl, wherein
R.sup.1 is optionally substituted with one or more deuterium atoms;
and R.sup.2 is selected from CH.sub.3, CH.sub.2D, CHD.sub.2, and
CD.sub.3; provided that at least one deuterium atom is present at
ether R.sup.1 or R.sup.2.
2. The compound of claim 1, wherein R.sup.1 is
--O--(C.sub.2-C.sub.4)alkyl substituted with one or more deuterium
atoms.
3. The compound of claim 1 or 2, wherein R.sup.2 is CH.sub.3 or
CD.sub.3.
4. The compound of claim 1 or 2, wherein R.sup.1 is
--O--CD.sub.2CD.sub.3, --O--CD.sub.2CH.sub.3,
--O--CH.sub.2CD.sub.3, --O--CD(CD.sub.3).sub.2,
--O--CH(CD.sub.3).sub.2, --O--CD(CH.sub.3).sub.2,
--O--CD.sub.2CH(CH.sub.3).sub.2, --O--CH.sub.2CD(CH.sub.3).sub.2,
--O--CH.sub.2CH(CD.sub.3).sub.2, --O--CD.sub.2CD(CH.sub.3).sub.2,
--O--CD.sub.2CH(CD.sub.3).sub.2, --O--CH.sub.2CD(CD.sub.3).sub.2,
or --O--CD.sub.2CD(CD.sub.3).sub.2.
5. The compound of claim 4, wherein R.sup.1 is
--O--CD.sub.2CD.sub.3, --O--CD.sub.2CH.sub.3,
--O--CH.sub.2CD.sub.3, --O--CD(CD.sub.3).sub.2,
--O--CH(CD.sub.3).sub.2, or --O--CD(CH.sub.3).sub.2.
6. The compound of claim 5, wherein R.sup.1 is
--O--CD.sub.2CD.sub.3 or --O--CD(CD.sub.3).sub.2.
7. The compound of claim 6, wherein R.sup.1 is
--O--CD(CD.sub.3).sub.2.
8. The compound of claim 3, wherein the compound is selected from
any one of the compounds set forth in the table below:
TABLE-US-00008 Compound No. R.sup.1 R.sup.2 100
--O--CD.sub.2CD.sub.3 CD.sub.3 101 --O--CD.sub.2CH.sub.3 CD.sub.3
102 --O--CD(CD.sub.3).sub.2 CD.sub.3 103 --O--CD(CH.sub.3).sub.2
CD.sub.3 104 --O--CD.sub.2CD.sub.3 CH.sub.3 105
--O--CD.sub.2CH.sub.3 CH.sub.3 106 --O--CD(CD.sub.3).sub.2 CH.sub.3
107 --O--CD(CH.sub.3).sub.2 CH.sub.3
or a pharmaceutically acceptable salt thereof.
9. The compound of claim 1, wherein R.sup.1 is
--(C.sub.1-C.sub.4)alkyl which is optionally substituted with one
or more deuterium atoms.
10. The compound of claim 9, wherein R.sup.2 is CH.sub.3 or
CD.sub.3.
11. The compound of claim 10, wherein R.sup.1 is --CH.sub.3,
--CD.sub.3, --CH.sub.2CH.sub.3, --CD.sub.2CD.sub.3,
--CD.sub.2CH.sub.3, --CH.sub.2CD.sub.3, --CH(CH.sub.3).sub.2,
--CD(CD.sub.3).sub.2, --CH(CD.sub.3).sub.2, --CD(CH.sub.3).sub.2,
--CH.sub.2CH(CH.sub.3).sub.2, --CD.sub.2CH(CH.sub.3).sub.2,
--CH.sub.2CD(CH.sub.3).sub.2, --CH.sub.2CH(CD.sub.3).sub.2,
--CD.sub.2CD(CH.sub.3).sub.2, --CD.sub.2CH(CD.sub.3).sub.2,
--CH.sub.2CD(CD.sub.3).sub.2, or --CD.sub.2CD(CD.sub.3).sub.2.
12. The compound of claim 11, wherein R.sup.1 is --CD.sub.3,
--CD.sub.2CD.sub.3, --CD.sub.2CH.sub.3, --CH.sub.2CD.sub.3,
--CD(CD.sub.3).sub.2, --CH(CD.sub.3).sub.2, --CD(CH.sub.3).sub.2,
--CD.sub.2CH(CH.sub.3).sub.2, --CH.sub.2CD(CH.sub.3).sub.2,
--CH.sub.2CH(CD.sub.3).sub.2, --CD.sub.2CD(CH.sub.3).sub.2,
--CD.sub.2CH(CD.sub.3).sub.2, --CH.sub.2CD(CD.sub.3).sub.2, or
--CD.sub.2CD(CD.sub.3).sub.2.
13. The compound of claim 12, wherein R.sup.1 is --CD.sub.3,
--CD.sub.2CD.sub.3, or --CD.sub.2CD(CD.sub.3).sub.2.
14. The compound of claim 13, wherein R.sup.1 is --CD.sub.3.
15. The compound of claim 14, wherein R.sup.1 is --CH.sub.3,
--CH.sub.2CH.sub.3, --CH(CH.sub.3).sub.2, or
--CH.sub.2CH(CH.sub.3).sub.2 and R.sup.2 is selected from
CD.sub.3.
16. The compound of claim 10, selected from any one of:
##STR00020## or a pharmaceutically acceptable salt thereof.
17. The compound of claim 1, wherein any atom not designated as
deuterium is present at its natural isotopic abundance.
18. A pyrogen-free pharmaceutical composition comprising the
compound of claim 1 or a pharmaceutically acceptable salt thereof
and a pharmaceutically acceptable carrier.
19. The composition of claim 18, further comprising a second
therapeutic agent useful in treating a patient suffering from or
susceptible to a disease or condition selected from emotional
lability; pseudobulbar affect; autism; neurological disorders and
neurodegenerative diseases; brain injuries; disturbances of
consciousness disorders; cardiovascular diseases; glaucoma; tardive
dyskinesia; cancer; rheumatoid arthritis; diabetic neuropathy;
retinopathic diseases; diseases or disorders caused by
homocysteine-induced apoptosis; diseases or disorders caused by
elevated levels of homocysteine; chronic pain; intractable pain;
neuropathic pain, sympathetically mediated pain; pain associated
with gastrointestinal dysfunction; mouth pain; back pain; central
pain syndrome; complex regional pain syndrome; epileptic seizures;
epileptic hemiplegia; acquired epileptiform aphasia
(Landau-Kleffner syndrome); severe myoclonic epilepsy of infancy
(SMEI); early infantile epileptic encephalopathy; post-stroke
seizure; febrile seizures; post-traumatic seizures; tinnitus;
sexual dysfunction; intractable coughing; dermatitis; addiction
disorders; Rett syndrome (RTT); voice disorders due to uncontrolled
laryngeal muscle spasms; methotrexate neurotoxicity; and fatigue
caused by cancer.
20. The composition of claim 19, wherein the second therapeutic
agent is selected from quinidine, quinidine sulfate, oxycodone, and
gabapentin.
21. A method of treating a subject suffering from or susceptible to
a disease or condition selected from emotional lability;
pseudobulbar affect; autism; neurological disorders and
neurodegenerative diseases; brain injuries; disturbances of
consciousness disorders; cardiovascular diseases; glaucoma; tardive
dyskinesia; cancer; rheumatoid arthritis; diabetic neuropathy;
retinopathic diseases; diseases or disorders caused by
homocysteine-induced apoptosis; diseases or disorders caused by
elevated levels of homocysteine; chronic pain; intractable pain;
neuropathic pain, sympathetically mediated pain; pain associated
with gastrointestinal dysfunction; mouth pain; back pain; central
pain syndrome; complex regional pain syndrome; epileptic seizures;
epileptic hemiplegia; acquired epileptiform aphasia
(Landau-Kleffner syndrome); severe myoclonic epilepsy of infancy
(SMEI); early infantile epileptic encephalopathy; post-stroke
seizure; febrile seizures; post-traumatic seizures; tinnitus;
sexual dysfunction; intractable coughing; dermatitis; addiction
disorders; Rett syndrome (RTT); voice disorders due to uncontrolled
laryngeal muscle spasms; methotrexate neurotoxicity; and fatigue
caused by cancer; comprising the step of administering to the
subject in need thereof a therapeutically effective amount of a
pharmaceutical composition of claim 18.
22. The method of claim 21, wherein the subject is suffering from
or susceptible to diabetic neuropathic pain.
23. The method of claim 21, wherein the subject is suffering from
or susceptible to epileptic seizures.
24. A method of treating a subject suffering from or susceptible to
conditions related to exposure to chemical agents, comprising the
step of administering to the subject in need thereof a
therapeutically effective amount of a pharmaceutical composition of
claim 18.
25. A method of treating a subject suffering from or susceptible to
pain, comprising the step of administering to the subject in need
thereof a therapeutically effective amount of a pharmaceutical
composition of claim 18.
26. The composition of claim 18, further comprising a second
therapeutic agent useful in treating a patient suffering from or
susceptible to pain.
27. The composition of claim 18, further comprising a second
therapeutic agent useful in treating a patient suffering from or
susceptible to conditions related to exposure to chemical agents.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority as a continuation-in-part
to U.S. Ser. No. 13/119,905, filed Mar. 18, 2011, which is a
National Stage application under 35 U.S.C. .sctn.371 of
International Application No. PCT/US2009/057476, having an
International Filing Date of Sep. 18, 2009, which claims priority
to U.S. Provisional Application Ser. No. 61/098,511, filed Sep. 19,
2008, all of which are incorporated by reference herein in their
entireties.
TECHNICAL FIELD
[0002] This invention relates to novel morphinan compounds and
pharmaceutically acceptable salts thereof. This invention also
provides compositions comprising a compound of this invention and
the use of such compositions in methods of treating diseases and
conditions that are beneficially treated by administering a sigma-1
receptor agonist that also has NMDA antagonist activity.
BACKGROUND
[0003] Dextromethorphan, also known by its chemical name
(+)-3-methoxy-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan,
is currently one of the most widely used antitussives.
[0004] In addition to the physiological activity noted above,
dextromethorphan is also an agonist of the .sigma.2 receptor, an
N-methyl-D-aspartate (NMDA) antagonist, and an .alpha.3.beta.4
nicotinic receptor antagonist. Dextromethorphan inhibits
neurotransmitters, such as glutamate, from activating receptors in
the brain. Uptake of dopamine and serotonin are also inhibited.
[0005] Dextromethorphan is approved for use in over the counter
cough suppressant products. It is currently in Phase I clinical
trials for treating subjects with voice spasms, and Phase III
clinical studies for treating Rett Syndrome
(http://www.clinicaltrials.gov). Dextromethorphan is being studied
with other drugs in a Phase II clinical trial characterizing pain
processing mechanisms in subjects with irritable bowel syndrome
(http://www.clinicaltrials.gov/). Dextromethorphan is also in Phase
I clinical trials for treating hyperalgesia in methadone-maintained
subjects (http://www.clinicaltrials.gov/).
[0006] In addition, a combination of dextromethorphan hydrobromide
and quinidine sulfate is currently in Phase III clinical trials for
treating diabetic neuropathic pain (http://www.clinicaltrials.gov).
This drug combination, also know as Zenvia.RTM. and as
Neudexta.TM., is approved for treating Involuntary Emotional
Expression Disorder (TEED), also known as pseudobulbar affect.
[0007] Dextromethorphan is metabolized in the liver. Degradation
begins with O- and N-demethylation to form primary metabolites
dextrorphan and 3-methoxy-morphinan, both of which are further N-
and O-demethylated respectively to 3-hydroxy-morphinan. These three
metabolites are believed to be therapeutically active. A major
metabolic catalyst is the cytochrome P450 enzyme 2D6 (CYP2D6),
which is responsible for the O-demethylation reactions of
dextromethorphan and 3-methoxymorphinan. N-demethylation of
dextromethorphan and dextrorphan are catalyzed by enzymes in the
related CYP3A family. Conjugates of dextrorphan and
3-hydroxymorphinan can be detected in human plasma and urine within
hours of its ingestion.
[0008] Dextromethorphan abuse has been linked to its active
metabolite, dextrorphan. The PCP-like effects attributed to
dextromethorphan are more reliably produced by dextrorphan and thus
abuse potential in humans may be attributable to dextromethorphan
metabolism to dextrorphan. (Miller, S C et al., Addict Biol, 2005,
10(4): 325-7, Nicholson, K L et al., Psychopharmacology (Berl),
1999 Sep. 1, 146(1): 49-59, Pender, E S et al., Pediatr Emerg Care,
1991, 7: 163-7). One study on the psychotropic effects of
dextromethorphan found that people who are extensive metabolizers
(EM's) reported a greater abuse potential compared to poor
metabolizers (PM's) providing evidence that dextrorphan contributes
to dextromethorphan abuse potential (Zawertailo L A, et al., J Clin
Psychopharmacol, 1998 Aug., 18(4): 332-7).
[0009] A significant fraction of the population has a functional
deficiency in the CYP2D6 enzyme. Thus, because the major metabolic
pathway for dextromethorphan requires CYP2D6, the decreased
activity results in much greater duration of action and greater
drug effects in CYP2D6-deficient subjects. In addition to intrinsic
functional deficiency, certain medications, such as
antidepressants, are potent inhibitors of the CYP2D6 enzyme. With
its slower metabolism in some people, dextromethorphan, especially
in combination with other medication(s), can lead to serious
adverse events.
[0010] A longer than recommended duration of a drug in the body may
provide continued beneficial effects, but it may also create or
prolong undesired side effects. Undesirable side effects at
recommended doses of dextromethorphan therapy include nausea, loss
of appetite, diarrhea, drowsiness, dizziness, and impotence.
[0011] Dimemorfan, an analog of dextromethorphan, also known by its
chemical name as
(+)-(9.alpha.,13.alpha.,14.alpha.)-3,17-dimethylmorphinan, is a
non-narcotic antitussive. The antitussive activity of dimemorfan is
believed to result from direct action on the cough center in the
medulla (Ida, H., Clin Ther., 1997, Mar.-Apr.; 19(2): 215-31).
[0012] In addition to its antitussive properties, dimemorfan has
been shown to have anticonvulsant and neuroprotective effects
possibly arising from N-methyl-D-aspartate (NMDA) antagonism of
dextromethorphan (DM) and/or high-affinity DM .sigma. receptors
(Chou, Y-C. et al., Brain Res., 1999, Mar. 13; 821(2): 516-9).
Activation at the .sigma.-1 receptor has been found to provide
anticonvulsant action in rats and mice, like DM, but without the
behaviorial side effects produced by DM and its metabolite,
dextrorphan (Shin, E. J. et al., Br J Pharmacol., 2005, April;
144(7): 908-18 and Shin, E. J. et al., Behavioural Brain Research,
2004, 151: 267-276).
[0013] Metabolism of dimemorfan in humans is known to proceed
through cytochrome P450 catalyzed N-demethylation as well as
3-methyl oxidation. Greater than 98% of a dose of dimemorfan is
metabolized in healthy human males and none of the metabolites have
been shown to have antitussive effects (Chou Y--C., et al., Life
Sci., 2005, Jul. 1; 77(7): 735-45 and Chou Y--C., et al., J Pharm
Sci., 2009, Jul. 1-15).
[0014] Additionally, two ether analogs of dextromethorphan,
[(+)-3-ethoxy-17-methylmorphinan] also referred to herein as
"dextroethorphan," and [(+)-3-(2-propoxy)-17-methyl-morphinan] also
referred to herein as "dextroisoproporphan," have shown
anticonvulsant activity (Newman, A. et al., J Med. Chem., 1992,
35(22): 4135-42 and Tortella, F. et al., J Pharmacol and Exp
Therap., 1994, 268(2): 727-733) as well as neuroprotective effects
in rats (Tortella, F. et al., Neurosci. Lett., 1995, 198(2):
79-82).
[0015] Accordingly, it is desirable to provide new compounds that
have the beneficial activities of dextromethorphan, dimemorfan,
dextroethorphan and dextroisoproporphan and may also have other
benefits, e.g., reduced adverse side effects, with a decreased
metabolic liability to further extend its pharmacological effective
life, enhance subject compliance and, potentially, to decrease
population pharmacokinetic variability and/or decrease its
potential for dangerous drug-drug interactions or decrease the
likelihood of dextromethorphan abuse due to the formation of
untoward metabolites such as dextrorphan.
SUMMARY
[0016] Provided herein is a compound of Formula I:
##STR00001##
[0017] or a pharmaceutically acceptable salt thereof, wherein:
[0018] R.sup.1 is selected from --O--(C.sub.2-C.sub.4)alkyl and
--(C.sub.1-C.sub.4)alkyl, wherein R.sup.1 is optionally substituted
with one or more deuterium atoms; and
[0019] R.sup.2 is selected from CH.sub.3, CH.sub.2D, CHD.sub.2, and
CD.sub.3;
[0020] provided that at least one deuterium atom is present at
either R.sup.1 or R.sup.2.
[0021] In some embodiments, R.sup.2 is CH.sub.3 or CD.sub.3. In
some embodiments, R.sup.1 is --O--CH.sub.2CH.sub.3,
--O--CD.sub.2CD.sub.3, --O--CD.sub.2CH.sub.3,
--O--CH.sub.2CD.sub.3, --O--CH(CH.sub.3).sub.2,
--O--CD(CD.sub.3).sub.2, --O--CH(CD.sub.3).sub.2,
--O--CD(CH.sub.3).sub.2, --O--CH.sub.2CH(CH.sub.3).sub.2,
--O--CD.sub.2CH(CH.sub.3).sub.2, --O--CH.sub.2CD(CH.sub.3).sub.2,
--O--CH.sub.2CH(CD.sub.3).sub.2, --O--CD.sub.2CD(CH.sub.3).sub.2,
--O--CD.sub.2CH(CD.sub.3).sub.2, --O--CH.sub.2CD(CD.sub.3).sub.2,
or --O--CD.sub.2CD(CD.sub.3).sub.2.
[0022] In some embodiments R.sup.1 is --O--(C.sub.2-C.sub.4)alkyl
substituted with one or more deuterium atoms.
[0023] In some embodiments, R.sup.1 is --O--CD.sub.2CD.sub.3,
--O--CD.sub.2CH.sub.3, --O--CH.sub.2CD.sub.3,
--O--CD(CD.sub.3).sub.2, --O--CH(CD.sub.3).sub.2,
--O--CD(CH.sub.3).sub.2, --O--CD.sub.2CH(CH.sub.3).sub.2,
--O--CH.sub.2CD(CH.sub.3).sub.2, --O--CH.sub.2CH(CD.sub.3).sub.2,
--O--CD.sub.2CD(CH.sub.3).sub.2, --O--CD.sub.2CH(CD.sub.3).sub.2,
--O--CH.sub.2CD(CD.sub.3).sub.2, or
--O--CD.sub.2CD(CD.sub.3).sub.2.
[0024] In some embodiments, R.sup.1 is --O--CD.sub.2CD.sub.3,
--O--CD.sub.2CH.sub.3, --O--CH.sub.2CD.sub.3,
--O--CD(CD.sub.3).sub.2, --O--CH(CD.sub.3).sub.2, or
--O--CD(CH.sub.3).sub.2.
[0025] In some embodiments, R.sup.1 is --O--CD.sub.2CD.sub.3 or
--O--CD(CD.sub.3).sub.2.
[0026] In some embodiments, R.sup.1 is --O--CD(CD.sub.3).sub.2.
[0027] In some embodiments, a Formula I compound is selected from
any one of the compounds in Table 1 set forth below:
TABLE-US-00001 Compound No. R.sup.1 R.sup.2 100
--O--CD.sub.2CD.sub.3 CD.sub.3 101 --O--CD.sub.2CH.sub.3 CD.sub.3
102 --O--CD(CD.sub.3).sub.2 CD.sub.3 103 --O--CD(CH.sub.3).sub.2
CD.sub.3 104 --O--CD.sub.2CD.sub.3 CH.sub.3 105
--O--CD.sub.2CH.sub.3 CH.sub.3 106 --O--CD(CD.sub.3).sub.2 CH.sub.3
107 --O--CD(CH.sub.3).sub.2 CH.sub.3
[0028] In some embodiments of the compound of Formula I, R.sup.1 is
--(C.sub.1-C.sub.4)alkyl which is optionally substituted with one
or more deuterium atoms. In some of these embodiments, R.sup.2 is
CH.sub.3 or CD.sub.3. In some of these embodiments, R.sup.1 is
--CH.sub.3, --CD.sub.3, --CH.sub.2CH.sub.3, --CD.sub.2CD.sub.3,
--CD.sub.2CH.sub.3, --CH.sub.2CD.sub.3, --CH(CH.sub.3).sub.2,
--CD(CD.sub.3).sub.2, --CH(CD.sub.3).sub.2, --CD(CH.sub.3).sub.2,
--CH.sub.2CH(CH.sub.3).sub.2, --CD.sub.2CH(CH.sub.3).sub.2,
--CH.sub.2CD(CH.sub.3).sub.2, --CH.sub.2CH(CD.sub.3).sub.2,
--CD.sub.2CD(CH.sub.3).sub.2, --CD.sub.2CH(CD.sub.3).sub.2,
--CH.sub.2CD(CD.sub.3).sub.2, or --CD.sub.2CD(CD.sub.3).sub.2. In
some of these embodiments, R.sup.1 is --CD.sub.3,
--CD.sub.2CD.sub.3, --CD.sub.2CH.sub.3, --CH.sub.2CD.sub.3,
--CD(CD.sub.3).sub.2, --CH(CD.sub.3).sub.2, --CD(CH.sub.3).sub.2,
--CD.sub.2CH(CH.sub.3).sub.2, --CH.sub.2CD(CH.sub.3).sub.2,
--CH.sub.2CH(CD.sub.3).sub.2, --CD.sub.2CD(CH.sub.3).sub.2,
--CD.sub.2CH(CD.sub.3).sub.2, --CH.sub.2CD(CD.sub.3).sub.2, or
--CD.sub.2CD(CD.sub.3).sub.2. In some of these embodiments, R.sup.1
is --CD.sub.3, --CD.sub.2CD.sub.3, or --CD.sub.2CD(CD.sub.3).sub.2.
In some of these embodiments, R.sup.1 is --CD.sub.3. In some of
these embodiments, R.sup.1 is --CH.sub.3, --CH.sub.2CH.sub.3,
--CH(CH.sub.3).sub.2, or --CH.sub.2CH(CH.sub.3).sub.2 and R.sup.2
is selected from CD.sub.3.
[0029] In some embodiments, the compound of Formula I is selected
from any one of:
##STR00002##
[0030] In some embodiments of the compounds of Formula I, any atom
not designated as deuterium is present at its natural isotopic
abundance.
[0031] Also provided is a pyrogen-free pharmaceutical composition
comprising a compound of Formula I and a pharmaceutically
acceptable carrier. In some embodiments, the composition further
comprises a second therapeutic agent useful in treating a patient
suffering from or susceptible to a disease or condition selected
from emotional lability; pseudobulbar affect; autism; neurological
disorders; neurodegenerative diseases; brain injury; disturbances
of consciousness disorders; cardiovascular diseases; glaucoma;
tardive dyskinesia; diabetic neuropathy; retinopathic diseases;
diseases or disorders caused by homocysteine-induced apoptosis;
diseases or disorders caused by elevated levels of homocysteine;
pain, including but not limited to, chronic pain; intractable pain;
neuropathic pain; sympathetically mediated pain; and pain
associated with gastrointestinal dysfunction; epileptic seizures;
tinnitus; sexual dysfunction; intractable coughing; dermatitis;
addiction disorders; Rett syndrome (RTT); voice disorders due to
uncontrolled laryngeal muscle spasms; methotrexate neurotoxicity;
fatigue caused by cancer; and conditions related to exposure to
chemical agents. Such chemical agents may include toxic agents such
as, for example, (i) agents used in warfare or combat, such as for
example nerve gas, or (ii) industrial pollutants. In one
embodiment, the brain injury is traumatic brain injury. In one
embodiment, the sexual dysfunction is premature ejaculation.
[0032] In some embodiments, the second therapeutic agent is
selected from quinidine, quinidine sulfate, oxycodone, and
gabapentin.
[0033] Also provided is a method of treating a subject suffering
from or susceptible to a disease or condition selected from
emotional lability; pseudobulbar affect; autism; neurological
disorders; neurodegenerative diseases; brain injury; disturbances
of consciousness disorders; cardiovascular diseases; glaucoma;
tardive dyskinesia; diabetic neuropathy; retinopathic diseases;
diseases or disorders caused by homocysteine-induced apoptosis;
diseases or disorders caused by elevated levels of homocysteine;
pain, including but not limited to, chronic pain; intractable pain;
neuropathic pain; sympathetically mediated pain; and pain
associated with gastrointestinal dysfunction; epileptic seizures;
tinnitus; sexual dysfunction; intractable coughing; dermatitis;
addiction disorders; Rett syndrome (RTT); voice disorders due to
uncontrolled laryngeal muscle spasms; methotrexate neurotoxicity;
fatigue caused by cancer; and conditions related to exposure to
chemical agents, comprising the step of administering to the
subject in need thereof a therapeutically effective amount of a
pharmaceutical composition comprising a compound of Formula I. In
one embodiment, the brain injury is traumatic brain injury. In one
embodiment, the sexual dysfunction is premature ejaculation. In
some embodiments, the subject is suffering from or susceptible to
diabetic neuropathic pain.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] FIG. 1 depicts the metabolic stability of compounds of this
invention in CYP2D6 SUPERSOMES.TM..
[0035] FIG. 2, panels A and B, depict the metabolic stability of
dextroethorphan (panel A), dextroisoproporphan (panel B), and
compounds of this invention in human liver microsomes.
[0036] FIG. 3 depicts the metabolic stability of dimemorfan and of
compounds of this invention in human liver microsomes.
DETAILED DESCRIPTION
Definitions
[0037] The terms "ameliorate" and "treat" are used interchangeably
and include both therapeutic treatment and/or prophylactic
treatment (reducing the likelihood of development). Both terms mean
decrease, suppress, attenuate, diminish, arrest, or stabilize the
development or progression of a disease (e.g., a disease or
disorder delineated herein), lessen the severity of the disease or
improve the symptoms associated with the disease.
[0038] "Disease" means any condition or disorder that damages or
interferes with the normal function of a cell, tissue, or
organ.
[0039] It will be recognized that some variation of natural
isotopic abundance occurs in a synthesized compound depending upon
the origin of chemical materials used in the synthesis. Thus, a
preparation of dextromethorphan or dextromethorphan analogs will
inherently contain small amounts of deuterated isotopologues. The
concentration of naturally abundant stable hydrogen and carbon
isotopes, notwithstanding this variation, is small and immaterial
as compared to the degree of stable isotopic substitution of
compounds of this invention. See, for instance, Wada E et al.,
Seikagaku 1994, 66:15; Gannes L Z et al., Comp Biochem Physiol Mol
Integr Physiol 1998, 119:725. Unless otherwise stated, when a
position is designated specifically as "H" or "hydrogen", the
position is understood to have hydrogen at its natural abundance
isotopic composition. Also unless otherwise stated, when a position
is designated specifically as "D" or "deuterium", the position is
understood to have deuterium at an abundance that is at least 3340
times greater than the natural abundance of deuterium, which is
0.015% (i.e., the term "D" or "deuterium" indicates at least 50.1%
incorporation of deuterium).
[0040] The term "isotopic enrichment factor" as used herein means
the ratio between the isotopic abundance of D at a specified
position in a compound of this invention and the naturally
occurring abundance of that isotope. The natural abundance of
deuterium is 0.015%.
[0041] In other embodiments, a compound of this invention has an
isotopic enrichment factor for each deuterium present at a site
designated as a potential site of deuteration on the compound of at
least 3500 (52.5% deuterium incorporation), at least 4000 (60%
deuterium incorporation), at least 4500 (67.5% deuterium
incorporation), at least 5000 (75% deuterium), at least 5500 (82.5%
deuterium incorporation), at least 6000 (90% deuterium
incorporation), at least 6333.3 (95% deuterium incorporation), at
least 6466.7 (97% deuterium incorporation), at least 6600 (99%
deuterium incorporation), or at least 6633.3 (99.5% deuterium
incorporation). It is understood that the isotopic enrichment
factor of each deuterium present at a site designated as a site of
deuteration is independent of other deuterated sites. For example,
if there are two sites of deuteration on a compound one site could
be deuterated at 52.5% while the other could be deuterated at 75%.
The resulting compound would be considered to be a compound wherein
the isotopic enrichment factor is at least 3500 (52.5%).
[0042] The term "isotopologue" refers to a species that has the
same chemical structure and formula as a specific compound of this
invention, with the exception of the positions of isotopic
substitution and/or level of isotopic enrichment at one or more
positions, e.g., H vs. D.
[0043] The term "compound," as used herein, refers to a collection
of molecules having an identical chemical structure, except that
there may be isotopic variation among the constituent atoms of the
molecules. Thus, it will be clear to those of skill in the art that
a compound represented by a particular chemical structure
containing indicated deuterium atoms, will also contain lesser
amounts of isotopologues having hydrogen atoms at one or more of
the designated deuterium positions in that structure. The relative
amount of such isotopologues in a compound of this invention will
depend upon a number of factors including the isotopic purity of
deuterated reagents used to make the compound and the efficiency of
incorporation of deuterium in the various synthesis steps used to
prepare the compound. However, as set forth above the relative
amount of such isotopologues will be less than 49.9% of the
compound.
[0044] A salt of a compound of this invention is formed between an
acid and a basic group of the compound, such as an amino functional
group, or a base and an acidic group of the compound, such as a
carboxyl functional group. According to another embodiment, the
compound is a pharmaceutically acceptable acid addition salt.
[0045] The term "pharmaceutically acceptable," as used herein,
refers to a component that is, within the scope of sound medical
judgment, suitable for use in contact with the tissues of humans
and other mammals without undue toxicity, irritation, allergic
response and the like, and are commensurate with a reasonable
benefit/risk ratio. A "pharmaceutically acceptable salt" means any
suitable salt that, upon administration to a recipient, is capable
of providing, either directly or indirectly, a compound of this
invention. A "pharmaceutically acceptable counterion" is an ionic
portion of a salt that is not toxic when released from the salt
upon administration to a recipient.
[0046] Acids commonly employed to form pharmaceutically acceptable
salts include inorganic acids such as hydrogen bisulfide,
hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid
and phosphoric acid, as well as organic acids such as
para-toluenesulfonic acid, salicylic acid, tartaric acid,
bitartaric acid, ascorbic acid, maleic acid, besylic acid, fumaric
acid, gluconic acid, glucuronic acid, formic acid, glutamic acid,
methanesulfonic acid, ethanesulfonic acid, benzenesulfonic acid,
lactic acid, oxalic acid, para-bromophenylsulfonic acid, carbonic
acid, succinic acid, citric acid, benzoic acid and acetic acid, as
well as related inorganic and organic acids. Such pharmaceutically
acceptable salts thus include sulfate, pyrosulfate, bisulfate,
sulfite, bisulfate, phosphate, monohydrogenphosphate,
dihydrogenphosphate, metaphosphate, pyrophosphate, chloride,
bromide, iodide, acetate, propionate, decanoate, caprylate,
acrylate, formate, isobutyrate, caprate, heptanoate, propiolate,
oxalate, malonate, succinate, suberate, sebacate, fumarate,
maleate, butyne-1,4-dioate, hexyne-1,6-dioate, benzoate,
chlorobenzoate, methylbenzoate, dinitrobenzoate, hydroxybenzoate,
methoxybenzoate, phthalate, terephthalate, sulfonate, xylene
sulfonate, phenylacetate, phenylpropionate, phenylbutyrate,
citrate, lactate, .beta.-hydroxybutyrate, glycolate, maleate,
tartrate, methanesulfonate, propanesulfonate,
naphthalene-1-sulfonate, naphthalene-2-sulfonate, mandelate and
other salts. In one embodiment, pharmaceutically acceptable acid
addition salts include those formed with mineral acids such as
hydrochloric acid and hydrobromic acid, and especially those formed
with organic acids such as maleic acid.
[0047] The term "stable compounds," as used herein, refers to
compounds which possess stability sufficient to allow for their
manufacture and which maintain the integrity of the compound for a
sufficient period of time to be useful for the purposes detailed
herein (e.g., formulation into therapeutic products, intermediates
for use in production of therapeutic compounds, isolatable or
storable intermediate compounds, treating a disease or condition
responsive to therapeutic agents).
[0048] "Stereoisomer" refers to both enantiomers and diastereomers.
"D" refers to deuterium. "Tert", ".sup.t", and "t" each refer to
tertiary. "US" refers to the United States of America. "FDA" refers
to Food and Drug Administration. "NDA" refers to New Drug
Application. "rt" and "RT" refer to room temperature. "h" refers to
hours. "DMF" refers to dimethylformamide. "TsOH" refers to
p-toluenesulfonic acid.
[0049] Throughout this specification, a variable may be referred to
generally (e.g.,"each R") or may be referred to specifically (e.g.,
R.sup.1 or R.sup.2). Unless otherwise indicated, when a variable is
referred to generally, it is meant to include all specific
embodiments of that particular variable.
Therapeutic Compounds
[0050] The present invention provides a compound of Formula I:
##STR00003##
[0051] or a pharmaceutically acceptable salt thereof, wherein:
[0052] R.sup.1 is --O--(C.sub.2-C.sub.4)alkyl or
--(C.sub.1-C.sub.4)alkyl, wherein R.sup.1 is optionally substituted
with one or more deuterium atoms; and
[0053] R.sup.2 is CH.sub.3, CH.sub.2D, CHD.sub.2, or CD.sub.3;
[0054] provided that at least one deuterium atom is present at
either R.sup.1 or R.sup.2.
[0055] The preferred stereochemistry of the present compounds is
based on the stereochemistry of morphinan compounds such as
dextromethorphan, which exists as the dextrorotatory enantiomer of
levorphanol.
[0056] One embodiment of the invention provides a compound of
Formula I wherein R.sup.1 is --O--(C.sub.2-C.sub.4)alkyl which is
optionally substituted with one or more deuterium atoms. In one
aspect of this embodiment, R.sup.1 is --O--CH.sub.2CH.sub.3,
--O--CD.sub.2CD.sub.3, --O--CD.sub.2CH.sub.3,
--O--CH.sub.2CD.sub.3, --O--CH(CH.sub.3).sub.2,
--O--CD(CD.sub.3).sub.2, --O--CH(CD.sub.3).sub.2,
--O--CD(CH.sub.3).sub.2, --O--CH.sub.2CH(CH.sub.3).sub.2,
--O--CD.sub.2CH(CH.sub.3).sub.2, --O--CH.sub.2CD(CH.sub.3).sub.2,
--O--CH.sub.2CH(CD.sub.3).sub.2, --O--CD.sub.2CD(CH.sub.3).sub.2,
--O--CD.sub.2CH(CD.sub.3).sub.2, --O--CH.sub.2CD(CD.sub.3).sub.2,
or --O--CD.sub.2CD(CD.sub.3).sub.2.
[0057] In another aspect, R.sup.1 is --O--CD.sub.2CD.sub.3,
--O--CD.sub.2CH.sub.3, --O--CH.sub.2CD.sub.3,
--O--CD(CD.sub.3).sub.2, --O--CH(CD.sub.3).sub.2,
--O--CD(CH.sub.3).sub.2, --O--CD.sub.2CH(CH.sub.3).sub.2,
--O--CH.sub.2CD(CH.sub.3).sub.2, --O--CH.sub.2CH(CD.sub.3).sub.2,
--O--CD.sub.2CD(CH.sub.3).sub.2, --O--CD.sub.2CH(CD.sub.3).sub.2,
--O--CH.sub.2CD(CD.sub.3).sub.2, or
--O--CD.sub.2CD(CD.sub.3).sub.2.
[0058] In another aspect, R.sup.1 is --O--CD.sub.2CD.sub.3,
--O--CD.sub.2CH.sub.3, --O--CH.sub.2CD.sub.3,
--O--CD(CD.sub.3).sub.2, --O--CH(CD.sub.3).sub.2, or
--O--CD(CH.sub.3).sub.2.
[0059] In another aspect, R.sup.1 is --O--CD.sub.2CD.sub.3 or
--O--CD(CD.sub.3).sub.2. In another aspect, R.sup.1 is
--O--CD.sub.2CD.sub.3.
[0060] In another aspect, R.sup.1 is --O--CD(CD.sub.3).sub.2.
[0061] Another embodiment of Formula I provides a compound of
Formula I wherein R.sup.1 is a deuterated
--O--(C.sub.2-C.sub.4)alkyl and R.sup.2 is --CD.sub.3 or
--CH.sub.3. In one aspect of this embodiment, R.sup.2 is
--CD.sub.3. In another aspect R.sup.2 is --CH.sub.3.
[0062] Each of the above aspects of R.sup.1 may be combined with
each of the above aspects of R.sup.2 to form further embodiments of
this invention.
[0063] Examples of specific compounds where R.sup.1 is
--O--(C.sub.2-C.sub.4)alkyl include those shown in Table 1:
TABLE-US-00002 TABLE 1 Exemplary Compounds of Formula I (R.sup.1 is
--O--(C.sub.2--C.sub.4)alkyl) Compound No. R.sup.1 R.sup.2 100
--O--CD.sub.2CD.sub.3 CD.sub.3 101 --O--CD.sub.2CH.sub.3 CD.sub.3
102 --O--CD(CD.sub.3).sub.2 CD.sub.3 103 --O--CD(CH.sub.3).sub.2
CD.sub.3 104 --O--CD.sub.2CD.sub.3 CH.sub.3 105
--O--CD.sub.2CH.sub.3 CH.sub.3 106 --O--CD(CD.sub.3).sub.2 CH.sub.3
107 --O--CD(CH.sub.3).sub.2 CH.sub.3
[0064] or a pharmaceutically acceptable salt thereof.
[0065] Another embodiment of this invention provides compounds of
Formula I wherein R.sup.1 is --(C.sub.1-C.sub.4)alkyl which is
optionally substituted with one or more deuterium atoms. In one
aspect of this embodiment, R.sup.1 is --CH.sub.3, --CD.sub.3,
--CH.sub.2CH.sub.3, --CD.sub.2CD.sub.3, --CD.sub.2CH.sub.3,
--CH.sub.2CD.sub.3, --CH.sub.2CH.sub.2CH.sub.3,
--CD.sub.2CH.sub.2CH.sub.3, --CD.sub.2CD.sub.2CH.sub.3,
--CD.sub.2CD.sub.2CD.sub.3, --CH.sub.2CD.sub.2CH.sub.3,
--CH.sub.2CD.sub.2CD.sub.3, --CH.sub.2CH.sub.2CD.sub.3,
--CH(CH.sub.3).sub.2, --CD(CD.sub.3).sub.2, --CH(CD.sub.3).sub.2,
--CD(CH.sub.3).sub.2, --CH.sub.2CH.sub.2CH.sub.2CH.sub.3,
--CD.sub.2CH.sub.2CH.sub.2CH.sub.3,
--CD.sub.2CD.sub.2CH.sub.2CH.sub.3,
--CD.sub.2CD.sub.2CD.sub.2CH.sub.3,
--CD.sub.2CD.sub.2CD.sub.2CD.sub.3,
--CD.sub.2CH.sub.2CD.sub.2CH.sub.3,
--CD.sub.2CH.sub.2CH.sub.2CD.sub.3,
--CD.sub.2CH.sub.2CD.sub.2CD.sub.3,
--CH.sub.2CD.sub.2CH.sub.2CH.sub.3,
--CH.sub.2CH.sub.2CD.sub.2CH.sub.3,
--CH.sub.2CH.sub.2CH.sub.2CD.sub.3,
--CH.sub.2CD.sub.2CD.sub.2CH.sub.3,
--CH.sub.2CD.sub.2CH.sub.2CD.sub.3,
--CH.sub.2CH.sub.2CD.sub.2CD.sub.3, --CH(CH.sub.3)CH.sub.2CH.sub.3,
--CD(CH.sub.3)CH.sub.2CH.sub.3, --CD(CD.sub.3)CH.sub.2CH.sub.3,
--CD(CD.sub.3)CD.sub.2CH.sub.3, --CD(CD.sub.3)CD.sub.2CD.sub.3,
--CD(CH.sub.3)CD.sub.2CH.sub.3, --CD(CH.sub.3)CD.sub.2CH.sub.3,
--CD(CH.sub.3)CH.sub.2CD.sub.3, --CH(CD.sub.3)CH.sub.2CH.sub.3,
--CH(CH.sub.3)CD.sub.2CH.sub.3, --CH(CH.sub.3)CH.sub.2CD.sub.3,
--CH(CD.sub.3)CD.sub.2CH.sub.3, CH(CD.sub.3)CH.sub.2CD.sub.3,
--CH(CH.sub.3)CD.sub.2CD.sub.3, --CH.sub.2CH(CH.sub.3).sub.2,
--CD.sub.2CH(CH.sub.3).sub.2, --CH.sub.2CD(CH.sub.3).sub.2,
--CH.sub.2CH(CD.sub.3).sub.2, --CD.sub.2CD(CH.sub.3).sub.2,
--CD.sub.2CH(CD.sub.3).sub.2, --CH.sub.2CD(CD.sub.3).sub.2, or
--CD.sub.2CD(CD.sub.3).sub.2. In another aspect, R.sup.1 is
--CH.sub.3, --CH.sub.2CH.sub.3, --CH(CH.sub.3).sub.2, or
--CH.sub.2CH(CH.sub.3).sub.2 and R.sup.2 is selected from CD.sub.3.
In another aspect, R.sup.1 is --CD.sub.3, --CD.sub.2CD.sub.3,
--CD.sub.2CH.sub.3, --CH.sub.2CD.sub.3, --CD(CD.sub.3).sub.2,
--CH(CD.sub.3).sub.2, --CD(CH.sub.3).sub.2,
--CD.sub.2CH(CH.sub.3).sub.2, --CH.sub.2CD(CH.sub.3).sub.2,
--CH.sub.2CH(CD.sub.3).sub.2, --CD.sub.2CD(CH.sub.3).sub.2,
--CD.sub.2CH(CD.sub.3).sub.2, --CH.sub.2CD(CD.sub.3).sub.2, or
--CD.sub.2CD(CD.sub.3).sub.2. In another aspect, R.sup.1 is
--CD.sub.3, --CD.sub.2CD.sub.3, or --CD.sub.2CD(CD.sub.3).sub.2. In
another aspect, R.sup.1 is --CD.sub.3. Each of these aspects of
R.sup.1 may be combined with the below aspects of R.sup.2 to
provide further embodiments of this invention.
[0066] Another embodiment of this invention provides compounds of
Formula I wherein R.sup.1 is a deuterated --(C.sub.1-C.sub.4)alkyl
and wherein R.sup.2 is --CH.sub.3 or --CD.sub.3. In one aspect of
this embodiment, R.sup.2 is --CH.sub.3. In another aspect, R.sup.2
is --CD.sub.3.
[0067] Examples of specific compounds of Formula I where R.sup.1 is
--(C.sub.1-C.sub.4)alkyl include Compounds 108, 109 and 110 shown
below:
##STR00004##
[0068] or a pharmaceutically acceptable salt thereof.
[0069] In another set of embodiments, any atom not designated as
deuterium in any of the embodiments set forth above is present at
its natural isotopic abundance.
[0070] In another set of embodiments, the compound of Formula I is
purified, e.g., the compound of Formula I is present at a purity of
at least 50.1% by weight (e.g., at least 52.5%, 55%, 60%, 65%, 70%,
75%, 80%, 85%, 90%, 95%, 97%, 98%, 98.5%, 99%, 99.5% or 99.9%) of
the total amount of isotopologues of Formula I present,
respectively. Thus, in some embodiments, a composition comprising a
compound of Formula I can include a distribution of isotopologues
of the compound, provided at least 50.1% of the isotopologues by
weight are the recited compound.
[0071] In another set of embodiments, the compounds of Formula I
are provided in isolated form, e.g., the compound is not in a cell
or organism and the compound is separated from some or all of the
components that typically accompany it in nature.
[0072] In some embodiments, any position in the compound of Formula
I designated as having D has a minimum deuterium incorporation of
at least 50.1% (e.g., at least 52.5%, at least 60%, at least 67.5%,
at least 75%, at least 82.5%, at least 90%, at least 95%, at least
97%, at least 99%, or at least 99.5%) at the designated position(s)
of the compound of Formula I. Thus, in some embodiments, a
composition comprising a compound of Formula I can include a
distribution of isotopologues of the compound, provided at least
50.1% of the isotopologues include a D at the designated
position(s).
[0073] In some embodiments, a compound of Formula I is
"substantially free of" other isotopologues of the compound, e.g.,
less than 49.9%, less than 25%, less than 10%, less than 5%, less
than 2%, less than 1%, or less than 0.5% of other isotopologues are
present.
[0074] The synthesis of compounds of Formula I can be readily
achieved by reference to the Exemplary Syntheses and Examples
disclosed herein, and by use of procedures and intermediates
analogous to those disclosed, for instance, in Schnider, O. &
Grussner, A., Hely. Chim. Acta., 1951, 34: 2211; Grussner, A. &
Schnider, O.; GB 713146 (1954); Toyo Pharma K. K., Japan JP
60089474 A (1983); Newman, A. H. et al., J. Med. Chem., 1992, 35:
4135. Such methods can be carried out by utilizing corresponding
deuterated and, optionally, other isotope-containing reagents
and/or intermediates to synthesize the compounds delineated herein,
or by invoking standard synthetic protocols known in the art for
introducing isotopic atoms to a chemical structure.
Exemplary Syntheses
[0075] The following deuterated reagents and building blocks which
may be of use in preparing compounds of Formula I are commercially
available: iodoethane-d.sub.5, ethyl-2,2,2-d.sub.3 iodide,
ethyl-1,1-d.sub.2 iodide, isopropyl-d.sub.7 iodide,
isopropyl-d.sub.7 bromide, isopropyl-1,1,1,3,3,3-d.sub.6 iodide,
and 1,1,1,3,3,3-d.sub.6 bromide.
[0076] A convenient method for synthesizing compounds of Formula I
wherein R.sup.1 is --O--(C.sub.2-C.sub.4)alkyl is depicted in
Scheme 1.
##STR00005## ##STR00006##
[0077] Treatment of the known 17-ethoxycarbonyl-3-methoxy-morphinan
(10) (for its preparation, see: Murdter, T. E. et al., Journal of
Labelled Compounds and Radiopharmaceuticals 2002, 45: 1153-1158)
with boron tribromide according to the procedure described by
Newman, A. H. et al., Journal of Medicinal Chemistry 1992, 35:
4135-4142, affords the 17-ethoxycarbonyl-3-hydroxy-morphinan (11).
Treatment of the 3-hydroxy-morphinan 11 with the appropriately
deuterated alkyl iodide in the presence of potassium carbonate in a
manner analogous to the procedure described in the aforementioned
paper gives the deuterated 17-ethoxycarbonyl-3-alkoxy-morphinans
(12). Reduction of the carbamate of the morphinan 12 with either
lithium aluminum hydride or lithium aluminum deuteride in THF in a
manner analogous to that described by Newman affords the deuterated
3-alkoxy-17-methyl-morphinan (13) or the
3-alkoxy-17-trideuteromethyl-morphinan (14) compounds of Formula I,
respectively.
[0078] A convenient method for synthesizing compounds of Formula I
wherein R.sup.1 is --(C.sub.1-C.sub.4)alkyl is depicted in Scheme
2.
##STR00007## ##STR00008##
[0079] Treatment of 17-ethoxycarbonyl-3-hydroxy-morphinan (11) with
N-Phenyl-trifluoromethanesulfonimide according to the procedure
described by Kim, C.-H. in US 2005/0256147 A1 affords the
corresponding phenolic triflate (15). Palladium catalyzed
cross-coupling of 15 with the appropriately deuterated
(C.sub.1-C.sub.4)alkyl boronic acid (16) in a manner analogous to
the procedure from the aforementioned patent gives the deuterated
17-ethoxycarbonyl-3-(C.sub.1-C.sub.4)alkyl-morphinans (17).
Reduction of the carbamate of morphinan 17 with either lithium
aluminum hydride or lithium aluminum deuteride in THF in a manner
analogous to the procedure described by Newman, A. H. et al.,
Journal of Medicinal Chemistry 1992, 35: 4135-4142 affords the
deuterated 3-(C.sub.1-C.sub.4)alkyl-17-methyl-morphinan or the
3-(C.sub.1-C.sub.4)alkyl-17-trideuteromethyl-morphinan compounds of
Formula I, respectively.
[0080] The alkylboronic acid reagent 16 used in Scheme 2 is
prepared as described above in Scheme 3.
##STR00009##
[0081] Treatment of appropriately deuterated (C.sub.1-C.sub.4)alkyl
halide (20) with elemental lithium in pentane in a manner analogous
to the procedure described by Dawildowski, D. et al., in WO
2005/082911 A1 affords the corresponding (C.sub.1-C.sub.4)alkyl
lithium anion, which may be immediately treated with triisopropyl
borate followed by hydrolysis with aqueous hydrogen chloride in a
manner analogous to the procedure described by Brown, H. C. et al.,
Organometallics 1985, 4: 816-821 to afford the appropriately
deuterated (C.sub.1-C.sub.4)alkyl boronic acids (16).
[0082] The specific approaches and compounds shown above are not
intended to be limiting. The chemical structures in the schemes
herein depict variables that are hereby defined commensurately with
chemical group definitions (moieties, atoms, etc.) of the
corresponding position in the compound formulae herein, whether
identified by the same variable name (i.e., R.sup.1 or R.sup.2) or
not. The suitability of a chemical group in a compound structure
for use in the synthesis of another compound is within the
knowledge of one of ordinary skill in the art. Additional methods
of synthesizing compounds of Formula I and their synthetic
precursors, including those within routes not explicitly shown in
schemes herein, are within the means of chemists of ordinary skill
in the art. Synthetic chemistry transformations and protecting
group methodologies (protection and deprotection) useful in
synthesizing the applicable compounds are known in the art and
include, for example, those described in Larock R, Comprehensive
Organic Transformations, VCH Publishers (1989); Greene T W et al.,
Protective Groups in Organic Synthesis, 3.sup.rd Ed., John Wiley
and Sons (1999); Fieser L et al., Fieser and Fieser's Reagents for
Organic Synthesis, John Wiley and Sons (1994); and Paquette L, ed.,
Encyclopedia of Reagents for Organic Synthesis, John Wiley and Sons
(1995) and subsequent editions thereof.
[0083] Combinations of substituents and variables envisioned by
this invention are only those that result in the formation of
stable compounds.
Compositions
[0084] The invention also provides pyrogen-free compositions
comprising a compound of Formula I (e.g., including any of the
formulae herein), or a pharmaceutically acceptable salt of said
compound; and an acceptable carrier. In one embodiment, the
composition comprises an effective amount of the compound or
pharmaceutically acceptable salt thereof. Preferably, a composition
of this invention is formulated for pharmaceutical use ("a
pharmaceutical composition"), wherein the carrier is a
pharmaceutically acceptable carrier. The carrier(s) are
"acceptable" in the sense of being compatible with the other
ingredients of the formulation and, in the case of a
pharmaceutically acceptable carrier, not deleterious to the
recipient thereof in an amount used in the medicament.
[0085] Pharmaceutically acceptable carriers, adjuvants and vehicles
that may be used in the pharmaceutical compositions of this
invention include, but are not limited to, ion exchangers, alumina,
aluminum stearate, lecithin, serum proteins, such as human serum
albumin, buffer substances such as phosphates, glycine, sorbic
acid, potassium sorbate, partial glyceride mixtures of saturated
vegetable fatty acids, water, salts or electrolytes, such as
protamine sulfate, disodium hydrogen phosphate, potassium hydrogen
phosphate, sodium chloride, zinc salts, colloidal silica, magnesium
trisilicate, polyvinyl pyrrolidone, cellulose-based substances,
polyethylene glycol, sodium carboxymethylcellulose, polyacrylates,
waxes, polyethylene-polyoxypropylene-block polymers, polyethylene
glycol and wool fat.
[0086] If required, the solubility and bioavailability of the
compounds of the present invention in pharmaceutical compositions
may be enhanced by methods well-known in the art. One method
includes the use of lipid excipients in the formulation. See "Oral
Lipid-Based Formulations Enhancing the Bioavailability of Poorly
Water-Soluble Drugs (Drugs and the Pharmaceutical Sciences)," David
J. Hauss, ed. Informa Healthcare, 2007; and "Role of Lipid
Excipients in Modifying Oral and Parenteral Drug Delivery: Basic
Principles and Biological Examples," Kishor M. Wasan, ed.
Wiley-Interscience, 2006.
[0087] Another known method of enhancing bioavailability is the use
of an amorphous form of a compound of this invention optionally
formulated with a poloxamer, such as LUTROL.TM. and PLURONIC.TM.
(BASF Corporation), or block copolymers of ethylene oxide and
propylene oxide. See U.S. Pat. No. 7,014,866; and United States
patent publications 20060094744 and 20060079502.
[0088] The pharmaceutical compositions of the invention include
those suitable for oral, rectal, nasal, topical (including buccal
and sublingual), vaginal or parenteral (including subcutaneous,
intramuscular, intravenous and intradermal) administration. In
certain embodiments, the compound of the formulae herein is
administered transdermally (e.g., using a transdermal patch or
iontophoretic techniques). Other formulations may conveniently be
presented in unit dosage form, e.g., tablets, sustained release
capsules, and in liposomes, and may be prepared by any methods well
known in the art of pharmacy. See, for example, Remington: The
Science and Practice of Pharmacy, Lippincott Williams &
Wilkins, Baltimore, Md. (20th ed. 2000).
[0089] Such preparative methods include the step of bringing into
association with the molecule to be administered ingredients such
as the carrier that constitutes one or more accessory ingredients.
In general, the compositions are prepared by uniformly and
intimately bringing into association the active ingredients with
liquid carriers, liposomes or finely divided solid carriers, or
both, and then, if necessary, shaping the product.
[0090] In certain embodiments, the compound is administered orally.
Compositions of the present invention suitable for oral
administration may be presented as discrete units such as capsules,
sachets, or tablets each containing a predetermined amount of the
active ingredient; a powder or granules; a solution or a suspension
in an aqueous liquid or a non-aqueous liquid; an oil-in-water
liquid emulsion; a water-in-oil liquid emulsion; packed in
liposomes; or as a bolus, etc. Soft gelatin capsules can be useful
for containing such suspensions, which may beneficially increase
the rate of compound absorption.
[0091] In the case of tablets for oral use, carriers that are
commonly used include lactose and corn starch. Lubricating agents,
such as magnesium stearate, are also typically added. For oral
administration in a capsule form, useful diluents include lactose
and dried cornstarch. When aqueous suspensions are administered
orally, the active ingredient is combined with emulsifying and
suspending agents. If desired, certain sweetening and/or flavoring
and/or coloring agents may be added.
[0092] Compositions suitable for oral administration include
lozenges comprising the ingredients in a flavored basis, usually
sucrose and acacia or tragacanth; and pastilles comprising the
active ingredient in an inert basis such as gelatin and glycerin,
or sucrose and acacia.
[0093] Compositions suitable for parenteral administration include
aqueous and non-aqueous sterile injection solutions which may
contain anti-oxidants, buffers, bacteriostats and solutes which
render the formulation isotonic with the blood of the intended
recipient; and aqueous and non-aqueous sterile suspensions which
may include suspending agents and thickening agents. The
formulations may be presented in unit-dose or multi-dose
containers, for example, sealed ampules and vials, and may be
stored in a freeze dried (lyophilized) condition requiring only the
addition of the sterile liquid carrier, for example water for
injections, immediately prior to use. Extemporaneous injection
solutions and suspensions may be prepared from sterile powders,
granules and tablets.
[0094] Such injection solutions may be in the form, for example, of
a sterile injectable aqueous or oleaginous suspension. This
suspension may be formulated according to techniques known in the
art using suitable dispersing or wetting agents (such as, for
example, Tween 80) and suspending agents. The sterile injectable
preparation may also be a sterile injectable solution or suspension
in a non-toxic parenterally-acceptable diluent or solvent, for
example, as a solution in 1,3-butanediol. Among the acceptable
vehicles and solvents that may be employed are mannitol, water,
Ringer's solution and isotonic sodium chloride solution. In
addition, sterile, fixed oils are conventionally employed as a
solvent or suspending medium. For this purpose, any bland fixed oil
may be employed including synthetic mono- or diglycerides. Fatty
acids, such as oleic acid and its glyceride derivatives are useful
in the preparation of injectables, as are natural
pharmaceutically-acceptable oils, such as olive oil or castor oil,
especially in their polyoxyethylated versions. These oil solutions
or suspensions may also contain a long-chain alcohol diluent or
dispersant.
[0095] The pharmaceutical compositions of this invention may be
administered in the form of suppositories for rectal
administration. These compositions can be prepared by mixing a
compound of this invention with a suitable non-irritating excipient
which is solid at room temperature but liquid at the rectal
temperature and therefore will melt in the rectum to release the
active components. Such materials include, but are not limited to,
cocoa butter, beeswax and polyethylene glycols.
[0096] The pharmaceutical compositions of this invention may be
administered by nasal aerosol or inhalation. Such compositions are
prepared according to techniques well-known in the art of
pharmaceutical formulation and may be prepared as solutions in
saline, employing benzyl alcohol or other suitable preservatives,
absorption promoters to enhance bioavailability, fluorocarbons,
and/or other solubilizing or dispersing agents known in the art.
See, e.g.: Rabinowitz J D and Zaffaroni A C, U.S. Pat. No.
6,803,031, assigned to Alexza Molecular Delivery Corporation.
[0097] Topical administration of the pharmaceutical compositions of
this invention is especially useful when the desired treatment
involves areas or organs readily accessible by topical application.
For topical application topically to the skin, the pharmaceutical
composition should be formulated with a suitable ointment
containing the active components suspended or dissolved in a
carrier. Carriers for topical administration of the compounds of
this invention include, but are not limited to, mineral oil, liquid
petroleum, white petroleum, propylene glycol, polyoxyethylene
polyoxypropylene compound, emulsifying wax, and water.
Alternatively, the pharmaceutical composition can be formulated
with a suitable lotion or cream containing the active compound
suspended or dissolved in a carrier. Suitable carriers include, but
are not limited to, mineral oil, sorbitan monostearate, polysorbate
60, cetyl esters wax, cetearyl alcohol, 2-octyldodecanol, benzyl
alcohol, and water. The pharmaceutical compositions of this
invention may also be topically applied to the lower intestinal
tract by rectal suppository formulation or in a suitable enema
formulation. Topically-transdermal patches and iontophoretic
administration are also included in this invention. In one
embodiment, the invention is directed to the treatment of pain in a
subject, comprising topically administering to the subject in need
thereof a therapeutically effective amount of a pharmaceutical
composition comprising a compound of Formula I.
[0098] Application of the subject therapeutics may be local, so as
to be administered at the site of interest. Various techniques can
be used for providing the subject compositions at the site of
interest, such as injection, use of catheters, trocars,
projectiles, pluronic gel, stents, sustained drug release polymers
or other device which provides for internal access.
[0099] Thus, according to yet another embodiment, the compounds of
this invention may be incorporated into compositions for coating an
implantable medical device, such as prostheses, artificial valves,
vascular grafts, stents, or catheters. Suitable coatings and the
general preparation of coated implantable devices are known in the
art and are exemplified in U.S. Pat. Nos. 6,099,562; 5,886,026; and
5,304,121. The coatings are typically biocompatible polymeric
materials such as a hydrogel polymer, polymethyldisiloxane,
polycaprolactone, polyethylene glycol, polylactic acid, ethylene
vinyl acetate, and mixtures thereof. The coatings may optionally be
further covered by a suitable topcoat of fluorosilicone,
polysaccharides, polyethylene glycol, phospholipids or combinations
thereof to impart controlled release characteristics in the
composition. Coatings for invasive devices are to be included
within the definition of pharmaceutically acceptable carrier,
adjuvant or vehicle, as those terms are used herein.
[0100] According to another embodiment, the invention provides a
method of coating an implantable medical device comprising the step
of contacting said device with the coating composition described
above. It will be obvious to those skilled in the art that the
coating of the device will occur prior to implantation into a
mammal.
[0101] According to another embodiment, the invention provides a
method of impregnating an implantable drug release device
comprising the step of contacting said drug release device with a
compound or composition of this invention. Implantable drug release
devices include, but are not limited to, biodegradable polymer
capsules or bullets, non-degradable, diffusible polymer capsules
and biodegradable polymer wafers.
[0102] According to another embodiment, the invention provides an
implantable medical device coated with a compound or a composition
comprising a compound of this invention, such that said compound is
therapeutically active.
[0103] According to another embodiment, the invention provides an
implantable drug release device impregnated with or containing a
compound or a composition comprising a compound of this invention,
such that said compound is released from said device and is
therapeutically active.
[0104] Where an organ or tissue is accessible because of removal
from the subject, such organ or tissue may be bathed in a medium
containing a composition of this invention, a composition of this
invention may be painted onto the organ, or a composition of this
invention may be applied in any other convenient way.
[0105] In another embodiment, a composition of this invention
further comprises a second therapeutic agent. The second
therapeutic agent may be selected from any compound or therapeutic
agent known to have or that demonstrates advantageous properties
when administered with a compound having the same mechanism of
action as dextromethorphan. Such agents include those indicated as
being useful in combination with dextromethorphan, including but
not limited to, those described in U.S. Pat. Nos. 4,316,888;
4,446,140; 4,694,010; 4,898,860; 5,166,207; 5,336,980; 5,350,756;
5,366,980; 5,863,927; RE38,115; 6,197,830; 6,207,164; 6,583,152;
and 7,114,547; as well as in US patent publications 2001/0044446;
2002/0103109; 2004/0087479; 2005/0129783; 2005/0203125; and
2007/0191411.
[0106] Preferably, the second therapeutic agent is an agent useful
in the treatment or prevention of a disease or condition selected
from emotional lability; pseudobulbar affect; autism; neurological
disorders and neurodegenerative diseases, such as, e.g., dementia,
amyotrophic lateral sclerosis (ALS, also known as Lou Gehrig's
disease), Alzheimer's disease, Parkinson's disease, and multiple
sclerosis; brain injuries, such as, e.g., stroke, traumatic brain
injury, ischemic event, hypoxic event and neuronal death;
disturbances of consciousness disorders; cardiovascular diseases,
such as, e.g., peripheral vascular diseases, myocardial
infarctions, and atherosclerosis; glaucoma, tardive dyskinesia;
diabetic neuropathy; retinopathic diseases; diseases or disorders
caused by homocysteine-induced apoptosis; diseases or disorders
caused by elevated levels of homocysteine; chronic pain;
intractable pain; neuropathic pain, sympathetically mediated pain,
such as, allodynia, hyperpathia, hyperalgesia, dysesthesia,
paresthesia, deafferentation pain, and anesthesia dolorosa pain;
pain associated with gastrointestinal dysfunction, including, e.g.,
irritable bowel syndrome; mouth pain; epileptic seizures; tinnitus;
sexual dysfunction; intractable coughing; dermatitis; addiction
disorders, such as, e.g., addiction to or dependence on stimulants,
nicotine, morphine, heroine, other opiates, amphetamines, cocaine,
and alcohol; Rett syndrome (RTT); voice disorders due to
uncontrolled laryngeal muscle spasms, including e.g., abductor
spasmodic dysphonia, adductor spasmodic dysphonia, muscular tension
dysphonia, and vocal tremor; methotrexate neurotoxicity; and
fatigue caused by cancer. In one embodiment, the brain injury is
traumatic brain injury. In one embodiment, the sexual dysfunction
is premature ejaculation. In one embodiment, the second therapeutic
agent is selected from quinidine, quinidine sulfate, LBH589
(Novartis), oxycodone, and gabapentin.
[0107] In another embodiment, the invention provides separate
dosage forms of a compound of this invention and one or more of any
of the above-described second therapeutic agents, wherein the
compound and second therapeutic agent are associated with one
another. The term "associated with one another" as used herein
means that the separate dosage forms are packaged together or
otherwise attached to one another such that it is readily apparent
that the separate dosage forms are intended to be sold and
administered together (within less than 24 hours of one another,
consecutively or simultaneously).
[0108] In one embodiment of the pharmaceutical compositions of the
invention, the compound of the present invention is present in an
effective amount. As used herein, the term "effective amount"
refers to an amount which, when administered in a proper dosing
regimen, is sufficient to reduce or ameliorate the severity,
duration or progression of the disorder being treated, prevent the
advancement of the disorder being treated, cause the regression of
the disorder being treated, or enhance or improve the prophylactic
or therapeutic effect(s) of another therapy.
[0109] The interrelationship of dosages for animals and humans
(based on milligrams per meter squared of body surface) is
described in Freireich et al., (1966) Cancer Chemother. Rep 50:
219. Body surface area may be approximately determined from height
and weight of the subject. See, e.g., Scientific Tables, Geigy
Pharmaceuticals, Ardsley, N.Y., 1970, 537.
[0110] In one embodiment, an effective amount of a compound of this
invention can range from 0.4 mg to 400 mg, from 4.0 mg to 350 mg,
from 10 mg to 90 mg, or from 30 mg to 45 mg, inclusive, which can
be given once, twice, or up to three times daily depending on
various factors recognized by those skilled in the art.
[0111] Effective doses will also vary, as recognized by those
skilled in the art, depending on the diseases treated, the severity
of the disease, the route of administration, the sex, age and
general health condition of the subject, excipient usage, the
possibility of co-usage with other therapeutic treatments such as
use of other agents and the judgment of the treating physician. For
example, guidance for selecting an effective dose can be determined
by reference to the prescribing information for
dextromethorphan.
[0112] For pharmaceutical compositions that comprise a second
therapeutic agent, an effective amount of the second therapeutic
agent is between about 0.01% to 100% of the dosage normally
utilized in a monotherapy regime using just that agent. The normal
monotherapeutic dosages of these second therapeutic agents are well
known in the art. See, e.g., Wells et al., eds., Pharmacotherapy
Handbook, 2nd Edition, Appleton and Lange, Stamford, Conn. (2000);
PDR Pharmacopoeia, Tarascon Pocket Pharmacopoeia 2000, Deluxe
Edition, Tarascon Publishing, Loma Linda, Calif. (2000), each of
which references are incorporated herein by reference in their
entirety.
[0113] It is expected that some of the second therapeutic agents
referenced above will act synergistically with the compounds of
this invention. When this occurs, it will allow the effective
dosage of the second therapeutic agent and/or the compound of this
invention to be reduced from that required in a monotherapy. This
has the advantage of minimizing toxic side effects of either the
second therapeutic agent of a compound of this invention,
synergistic improvements in efficacy, improved ease of
administration or use and/or reduced overall expense of compound
preparation or formulation.
Methods of Treatment
[0114] In another embodiment, the invention provides a method of
modulating the activity of the sigma-1 and sigma-2 receptor,
N-methyl-D-aspartate (NMDA), or the activity of the .alpha.3.beta.4
nicotinic receptor in a cell, comprising contacting a cell with one
or more compounds of Formula I.
[0115] In another embodiment, the invention provides a method of
inhibiting neurotransmitters, such as glutamate, from activating
receptors in the brain and/or inhibiting the uptake of dopamine and
serotonin by administering a compound of Formula I.
[0116] According to another embodiment, the invention provides a
method of treating a subject suffering from, or susceptible to, a
disease or condition that is beneficially treated by
dextromethorphan comprising the step of administering to said
subject an effective amount of a compound of Formula I or a
pharmaceutically acceptable salt thereof or a composition
comprising such compound. Such diseases and conditions are well
known in the art and are disclosed in, but not limited to, those
described in U.S. Pat. Nos. 4,316,888; 4,446,140; 4,694,010;
4,898,860; 5,166,207; 5,336,980; 5,350,756; 5,366,980; 5,863,927;
RE38,115; 6,197,830; 6,207,164; 6,583,152; and 7,114,547; as well
as in US patent publications 2001/0044446; 2002/0103109;
2004/0087479; 2005/0129783; 2005/0203125; and 2007/0191411.
[0117] Such diseases and conditions include, but are not limited
to, emotional lability; pseudobulbar affect; autism; neurological
disorders and neurodegenerative diseases, such as, e.g., dementia,
amyotrophic lateral sclerosis (ALS, also known as Leu Gehrig's
disease), Alzheimer's disease, and multiple sclerosis; brain
injury; disturbances of consciousness disorders; cardiovascular
diseases, such as, e.g., peripheral vascular diseases, strokes,
myocardial infarctions, and atherosclerosis; glaucoma, tardive
dyskinesia; diabetic neuropathy; retinopathic diseases; diseases or
disorders caused by homocysteine-induced apoptosis; diseases or
disorders caused by elevated levels of homocysteine; pain,
including but not limited to, chronic pain; intractable pain;
neuropathic pain, sympathetically mediated pain, such as,
allodynia, hyperpathia, hyperalgesia, dysesthesia, paresthesia,
deafferentation pain, and anesthesia delorosa pain; pain associated
with gastrointestinal dysfunction, including, e.g., irritable bowel
syndrome; and mouth pain; epileptic seizures; tinnitus; sexual
dysfunction; intractable coughing; dermatitis; addiction disorders,
such as, e.g., addiction to or dependence on stimulants, nicotine,
morphine, heroine, other opiates, amphetamines, cocaine, and
alcohol; Rett syndrome (RTT); voice disorders due to uncontrolled
laryngeal muscle spasms, including e.g., abductor spasmodic
dysphonia, adductor spasmodic dysphonia, muscular tension
dysphonia, and vocal tremor; methotrexate neurotoxicity; fatigue
caused by cancer; and conditions related to exposure to chemical
agents. In one embodiment, the brain injury is traumatic brain
injury. In one embodiment, the sexual dysfunction is premature
ejaculation.
[0118] In one particular embodiment, the method of this invention
is used to treat a subject suffering from or susceptible to a
disease or condition selected from diabetic neuropathy, Rett
syndrome (RTT); voice disorders due to uncontrolled laryngeal
muscle spasms, including e.g., abductor spasmodic dysphonia,
adductor spasmodic dysphonia, muscular tension dysphonia, and vocal
tremor; methotrexate neurotoxicity; and fatigue caused by
cancer.
[0119] In one particular embodiment, the method is used to treat a
subject suffering from or susceptible neuropathic pain. In another
embodiment, the method is used to treat a subject suffering from
pseudobulbar affect.
[0120] In another particular embodiment, the method is used to
treat a subject suffering from generalized epileptic seizures or
partial epileptic seizures.
[0121] Methods delineated herein also include those wherein the
subject is identified as in need of a particular stated treatment.
Identifying a subject in need of such treatment can be in the
judgment of a subject or a health care professional and can be
subjective (e.g. opinion) or objective (e.g. measurable by a test
or diagnostic method).
[0122] In another embodiment, any of the above methods of treatment
comprises the further step of co-administering to the subject one
or more additional second therapeutic agents. The choice of second
therapeutic agent may be made from any second therapeutic agent
known to be useful for co-administration with dextromethorphan. The
choice of second therapeutic agent is also dependent upon the
particular disease or condition to be treated. Examples of second
therapeutic agents that may be employed in the methods of this
invention are those set forth above for use in combination
compositions comprising a compound of this invention and a second
therapeutic agent.
[0123] In particular, the combination therapies of this invention
include co-administering to a subject in need thereof a compound of
Formula I or pharmaceutically acceptable salt thereof, or a
composition comprising such compound or salt; and quinidine sulfate
wherein the subject is suffering from or susceptible to diabetic
neuropathy.
[0124] In another embodiment the invention provides a method of
treating a subject suffering from non-small cell lung cancer or
malignant pleural mesothelioma by co-administering to the subject
in need thereof a compound of Formula I, or a composition
comprising such compound; and LBH589.
[0125] The term "co-administered" as used herein means that the
additional second therapeutic agent may be administered together
with a compound of this invention as part of a single dosage form
(such as a composition of this invention comprising a compound of
the invention and an second therapeutic agent as described above)
or as separate, multiple dosage forms. Alternatively, the
additional agent may be administered prior to, consecutively with,
or following the administration of a compound of this invention. In
such combination therapy treatment, both the compounds of this
invention and the second therapeutic agent(s) are administered by
conventional methods. The administration of a composition of this
invention, comprising both a compound of the invention and a second
therapeutic agent, to a subject does not preclude the separate
administration of that same therapeutic agent, any other second
therapeutic agent or any compound of this invention to said subject
at another time during a course of treatment.
[0126] Effective amounts of these second therapeutic agents are
well known to those skilled in the art and guidance for dosing may
be found in patents and published patent applications referenced
herein, as well as in Wells et al., eds., Pharmacotherapy Handbook,
2nd Edition, Appleton and Lange, Stamford, Conn. (2000); PDR
Pharmacopoeia, Tarascon Pocket Pharmacopoeia 2000, Deluxe Edition,
Tarascon Publishing, Loma Linda, Calif. (2000), and other medical
texts. However, it is well within the skilled artisan's purview to
determine the second therapeutic agent's optimal effective-amount
range.
[0127] In one embodiment of the invention, where a second
therapeutic agent is administered to a subject, the effective
amount of the compound of this invention is less than its effective
amount would be where the second therapeutic agent is not
administered. In another embodiment, the effective amount of the
second therapeutic agent is less than its effective amount would be
where the compound of this invention is not administered. In this
way, undesired side effects associated with high doses of either
agent may be minimized Other potential advantages (including
without limitation improved dosing regimens and/or reduced drug
cost) will be apparent to those of skill in the art.
[0128] In yet another aspect, the invention provides the use of a
compound of Formula I alone or together with one or more of the
above-described second therapeutic agents in the manufacture of a
medicament, either as a single composition or as separate dosage
forms, for treatment or prevention in a subject of a disease,
disorder or symptom set forth above. Another aspect of the
invention is a compound of Formula I for use in the treatment or
prevention in a subject of a disease, disorder or symptom thereof
delineated herein.
[0129] According to another embodiment, the invention provides a
method of treating a subject suffering from, or susceptible to, a
disease or condition selected from depression (e.g., unipolar
depression, bipolar depression, reactive depression,
treatment-resistant depression, such as treatment-resistant bipolar
depression, treatment-resistant major depression, and
treatment-resistant major depression with suicidal ideation), brain
injury (e.g., traumatic brain injury), panic disorders, including
panic disorder with agoraphobia, agoraphobia without history of
panic disorder, and panic disorder without agoraphobia; anxiety;
phobias, including social phobia and specific phobia;
obsessive-compulsive disorder; urinary incontinence (e.g., urine
leakage, urge incontinence, stress incontinence, overflow
incontinence, mixed incontinence, dysuria, or increased urinary
urgency and/or frequency (overactive bladder syndrome)), and
interstitial cystitis comprising the step of administering to the
subject an effective amount of a compound of Formula I (as set
forth above) or of Formula II (as set forth below), or a
pharmaceutically acceptable salt thereof or a composition
comprising such compound of Formula I or Formula II. See, e.g.,
U.S. Pat. No. 6,562,835 and Lauterbach E., Medical Hypotheses 76
(2011):717-719.
[0130] A compound according to Formula II for use in the
above-described methods can be:
##STR00010##
wherein
[0131] R.sup.1 is selected from CH.sub.3, CH.sub.2D, CHD.sub.2,
CD.sub.3, CHF.sub.2, and CF.sub.3; and
[0132] R.sup.2 is selected from CH.sub.3, CH.sub.2D, CHD.sub.2, and
CD.sub.3.
[0133] In certain embodiments, when R.sup.1 is CH.sub.3, then
R.sup.2 is not CH.sub.3 or CD.sub.3. In other embodiments, when
R.sup.1 is CD.sub.3, then R.sup.2 is not CH.sub.3.
[0134] In one embodiment, R.sup.1 is selected from CH.sub.2D,
CHD.sub.2, CD.sub.3, CHF.sub.2, and CF.sub.3. In another
embodiment, R.sup.1 is selected from CH.sub.2D, CHD.sub.2, and
CD.sub.3. In a further embodiment, R.sup.1 is CD.sub.3. In another
embodiment, R.sup.1 is CF.sub.3. In a further embodiment, R.sup.1
is CHF.sub.2.
[0135] In one embodiment, R.sup.2 is CH.sub.3, CHD.sub.2 or
CD.sub.3. In another embodiment, R.sup.2 is CH.sub.3. In another
embodiment, R.sup.2 is CD.sub.3.
[0136] In yet another embodiment, the compound of Formula II is
selected from any one of the compounds set forth in Table 2.
TABLE-US-00003 TABLE 2 Exemplary Compounds of Formula II Compound
No. R.sup.1 R.sup.2 300 CD.sub.3 CH.sub.3 301 CD.sub.3 CD.sub.3 302
CD.sub.2H CD.sub.3 303 CD.sub.3 CD.sub.2H 304 CF.sub.3 CH.sub.3 305
CF.sub.3 CD.sub.3 306 CHF.sub.2 CH.sub.3 307 CHF.sub.2 CD.sub.3 308
CH.sub.3 CD.sub.3
[0137] In another set of embodiments, any atom not designated as
deuterium in any of the embodiments set forth above is present at
its natural isotopic abundance.
[0138] In another embodiment, any of the above methods of treatment
of panic disorders, including panic disorder with agoraphobia,
agoraphobia without history of panic disorder, and panic disorder
without agoraphobia; anxiety; phobias, including social phobia and
specific phobia; obsessive-compulsive disorder; brain injury,
including traumatic brain injury; depression; urinary incontinence;
or interstitial cystitis comprises the further step of
co-administering to the subject one or more additional second
therapeutic agents. The choice of second therapeutic agent may be
made from any second therapeutic agent known to be useful for
treating panic disorders, anxiety, phobias, obsessive-compulsive
disorder, brain injuries, depression, urinary incontinence, or
interstitial cystitis. In particular, the combination therapies of
this invention include co-administering to a subject in need
thereof a compound of Formula I or Formula II or a pharmaceutically
acceptable salt thereof, or a composition comprising such compound
or salt; and a second therapeutic agent selected from an
anticholinergic (such as oxybutynin, atropine, propantheline,
terodiline, dicyclomine), a sympathomimetic (such as ephedrine,
pseudoephedrine, phenylpropanolamine), a tricyclic antidepressant
(such as amitriptyline, imipramine, doxepin), an estrogen, an NMDA
receptor antagonist (e.g., a competitive NMDA receptor antagonist,
a non-competitive NMDA receptor antagonist), a selective serotonin
receptor antagonist, a selective serotonin reuptake inhibitor
(SSNRI), a serotonin-norepinephrine reuptake inhibitor (SNRT), a
monoamine oxidase inhibitor (MAOI), a direct acting antispasmodic
(such as flavoxate), lithium, or an anxiolyitic such as alprazolam,
chlordiazepoxide, clonazepam, diazepam, lorazepam, tofisopam,
buspirone, tandospirone, hydroxyzine, pregabalin, or venlafaxine.
In one embodiment, the subject is suffering from or susceptible to
urinary incontinence.
[0139] In addition, the combination therapies of this invention
include co-administering to a subject in need thereof a compound of
Formula I or Formula II or a pharmaceutically acceptable salt
thereof, or a composition comprising such compound or salt; and a
second therapeutic agent selected from ibuprofen, tricyclic
antidepressants, and pentosan when the subject is suffering from or
susceptible to interstitial cystitis.
Diagnostic Methods and Kits
[0140] The compounds and compositions of this invention are also
useful as reagents in methods for determining the concentration of
dextromethorphan in solution or biological sample such as plasma,
examining the metabolism of dextromethorphan and other analytical
studies.
[0141] According to one embodiment, the invention provides a method
of determining the concentration, in a solution or a biological
sample, of a non-deuterated analog of a compound of Formula I,
comprising the steps of:
[0142] a) adding a known concentration of a compound of Formula Ito
the solution of biological sample;
[0143] b) subjecting the solution or biological sample to a
measuring device that distinguishes the corresponding
non-deuterated analog from a compound of Formula I;
[0144] c) calibrating the measuring device to correlate the
detected quantity of the compound of Formula I with the known
concentration of the compound of Formula I added to the biological
sample or solution; and
[0145] d) measuring the quantity of the corresponding
non-deuterated analog in the biological sample with said calibrated
measuring device; and
[0146] e) determining the concentration of the corresponding
non-deuterated analog in the solution of sample using the
correlation between detected quantity and concentration obtained
for a compound of Formula I.
[0147] Measuring devices that can distinguish the corresponding
non-deuterated analog from a compound of Formula I include any
measuring device that can distinguish between two compounds that
differ from one another in isotopic abundance. Exemplary measuring
devices include a mass spectrometer, NMR spectrometer, or IR
spectrometer.
[0148] In another embodiment, a method for determining the amount
of a non-deuterated analog of a compound of Formula I in a solution
or a biological sample is provided, comprising: [0149] a) adding a
known amount of a compound of Formula I to the solution or
biological sample; [0150] b) detecting at least one signal for a
compound of Formula I and at least one signal for the corresponding
non-deuterated analog in a measuring device that is capable of
distinguishing the two compounds; [0151] c) correlating the at
least one signal detected for a compound of Formula I with the
known amount of the compound of Formula I added to the solution or
the biological sample; and [0152] d) determining the amount of the
corresponding non-deuterated analog in the solution or biological
sample using the correlation between the at least one signal
detected of the compound of Formula I and the amount added to the
solution or biological sample of a compound of Formula I.
[0153] In another embodiment, the invention provides a method of
evaluating the metabolic stability of a compound of Formula I
comprising the steps of contacting the compound of Formula I with a
metabolizing enzyme source for a period of time and comparing the
amount of the compound of Formula I with the metabolic products of
the compound of Formula I after the period of time.
[0154] In a related embodiment, the invention provides a method of
evaluating the metabolic stability of a compound of Formula I in a
subject following administration of the compound of Formula I. This
method comprises the steps of obtaining a serum, blood, tissue,
urine or feces sample from the subject at a period of time
following the administration of the compound of Formula I to the
subject; and comparing the amount of the compound of Formula I with
the metabolic products of the compound of Formula I in the serum,
blood, tissue, urine or feces sample.
[0155] The present invention also provides kits for use to treat
pseudobulbar disorder, diabetic neuropathy, Rett syndrome (RTT);
voice disorders due to uncontrolled laryngeal muscle spasms,
including e.g., abductor spasmodic dysphonia, adductor spasmodic
dysphonia, muscular tension dysphonia, and vocal tremor;
methotrexate neurotoxicity; and fatigue caused by cancer. These
kits comprise (a) a pharmaceutical composition comprising a
compound of Formula I or a salt thereof, wherein said
pharmaceutical composition is in a container; and (b) instructions
describing a method of using the pharmaceutical composition to
treat pseudobulbar affect; diabetic neuropathy; Rett syndrome
(RTT); voice disorders due to uncontrolled laryngeal muscle spasms,
including e.g., abductor spasmodic dysphonia, adductor spasmodic
dysphona, muscular tension dysphonia, and vocal tremor;
methotrexate neurotoxicity; and fatigue caused by cancer.
[0156] The present invention also provides kits for use to treat
panic disorders, including panic disorder with agoraphobia,
agoraphobia without history of panic disorder, and panic disorder
without agoraphobia; anxiety; phobias, including social phobia and
specific phobia; obsessive-compulsive disorder; brain injury,
including traumatic brain injury; and depression; urinary
incontinence; and interstitial cystitis, as described previously.
These kits comprise (a) a pharmaceutical composition comprising a
compound of Formula I or of Formula II or a salt thereof, wherein
the pharmaceutical composition is in a container; and (b)
instructions describing a method of using the pharmaceutical
composition to treat panic disorders, anxiety, phobias,
obsessive-compulsive disorder, brain injuries, urinary
incontinence, depression, and interstitial cystitis.
[0157] The container may be any vessel or other sealed or sealable
apparatus that can hold the pharmaceutical composition. Examples
include bottles, ampules, divided or multi-chambered holders
bottles, wherein each division or chamber comprises a single dose
of the composition, a divided foil packet wherein each division
comprises a single dose of the composition, or a dispenser that
dispenses single doses of the composition. The container can be in
any conventional shape or form as known in the art which is made of
a pharmaceutically acceptable material, for example a paper or
cardboard box, a glass or plastic bottle or jar, a re-sealable bag
(for example, to hold a "refill" of tablets for placement into a
different container), or a blister pack with individual doses for
pressing out of the pack according to a therapeutic schedule. The
container employed can depend on the exact dosage form involved,
for example a conventional cardboard box would not generally be
used to hold a liquid suspension. It is feasible that more than one
container can be used together in a single package to market a
single dosage form. For example, tablets may be contained in a
bottle, which is in turn contained within a box. In on embodiment,
the container is a blister pack.
[0158] The kits of this invention may also comprise a device to
administer or to measure out a unit dose of the pharmaceutical
composition. Such device may include an inhaler if said composition
is an inhalable composition; a syringe and needle if said
composition is an injectable composition; a syringe, spoon, pump,
or a vessel with or without volume markings if said composition is
an oral liquid composition; or any other measuring or delivery
device appropriate to the dosage formulation of the composition
present in the kit.
[0159] In an embodiment of the kits of this invention, the
composition comprising the second active agent may be in a vessel
or container that is separate from the vessel containing the
composition comprising a compound of Formula I and/or of Formula
II.
EXAMPLES
Example 1
Synthesis of
(+)-3-(Ethoxy-d.sub.5)-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-
-morphinan hydrochloride (100)
[0160] Compound 100 was prepared as outlined below. Details of the
synthesis follow.
##STR00011## ##STR00012##
[0161] Synthesis of
(+)-3-methoxy-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(free base, 8). To a reaction vessel was added
(+)-3-methoxy-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan,
HBr salt (7; 3.00 g, 8.5 mmol), NH.sub.3 in CH.sub.3OH (2.0 M, 8.5
mL, 17.0 mmol), and a stir bar. The reaction mixture was stirred at
RT for 1 h. The resulting material was concentrated on a rotary
evaporator, then diluted with CHCl.sub.3 (50 mL) and H.sub.2O (50
mL). The layers were separated and the water layer was extracted
with CHCl.sub.3 (50 mL). The combined organic layers were dried
over magnesium sulfate, filtered and concentrated on a rotary
evaporator to yield 2.88 g of 8 as a fluffy white solid.
[0162] .sup.1H-NMR (300 MHz, CDCl.sub.3): .delta. 1.12 (ddd,
J.sub.1=24.7, J.sub.2=12.6, J.sub.3=3.8, 1H), 1.23-1.43 (m, 5H),
1.49-1.52 (m, 1H), 1.62-1.65 (m, 1H), 1.72 (td, J.sub.1=12.6,
J.sub.2=4.9, 1H), 1.81 (dt, J.sub.1=12.6, J.sub.2=3.3, 1H), 2.07
(td, J.sub.1=12.6, J.sub.2=3.3, 1H), 2.33-2.47 (m, 5H), 2.57 (dd,
J.sub.1=18.1, J.sub.2=5.5, 1H), 2.79 (dd, J.sub.1=5.5, J.sub.2=3.3,
1H), 2.98 (d, J=18.1, 1H), 6.68 (dd, J.sub.1=8.2, J.sub.2=2.7, 1H),
6.80 (d, J=2.7, 1H), 7.02 (d, J=8.8, 1H).
[0163] Synthesis of
(+)-3-methoxy-(9.alpha.,13.alpha.,14.alpha.)-morphinan (9). The
solid
(+)-3-methoxy-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(8; 6.79 g, 25.1 mmol) was placed in a reaction vessel with
CHCl.sub.3 and a stir bar. K.sub.2CO.sub.3 (13.85 g, 100.2 mmol)
was added and the mixture was stirred at RT under an atmosphere of
N.sub.2 for 10 min before the addition of acetyl chloride (7.866 g,
100.2 mmol). The resulting reaction mixture, still under an
atmosphere of N.sub.2, was stirred under reflux conditions for 7 h,
then filtered through a pad of celite. The organic filtrate was
concentrated on a rotary evaporator and the resulting crude
material was dissolved in CH.sub.3OH then stirred under reflux
conditions for 1 h. The solution was concentrated on a rotary
evaporator then dried under vacuum to yield 6.78 g of 9 as an
off-white solid.
[0164] .sup.1H-NMR (300 MHz, CDCl.sub.3): .delta. 1.04-1.13 (m,
1H), 1.19-1.29 (m, 1H), 1.37-1.66 (m, 6H), 2.37 (d, J=13.5, 2H),
2.54 (bs, 1H), 2.80 (s, 2H), 2.95-2.99 (m, 1H), 3.12-3.18 (m, 2H),
3.48 (s, 1H), 3.71 (s, 3H), 6.76 (dd, J.sub.1=8.3, J.sub.2=2.6,
1H), 6.80 (d, J=2.3, 1H), 7.07 (d, J=8.3, 1H).
[0165] Synthesis of
(+)-17-ethylcarbamate-3-methoxy-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(10). To a reaction vessel fit with a stirbar was added 9 (6.025 g,
2.48 mmol) dissolved in CHCl.sub.3 (100 mL). Diisopropylethylamine
(DIEA; 16.32 g, 126.3 mmol) was added and the mixture was stirred
for 10 min at room temperature under nitrogen before the addition
of ethylchloroformate (13.094 g, 76.8 mmol). The reaction mixture
was stirred under reflux conditions under nitrogen for 3 h, at
which point TLC (20% ethylacetate/hexane) showed complete
consumption of the starting material. The organic layer was removed
and washed first with 1M HCl, and then with saturated NaHCO.sub.3.
The aqueous layers from each wash were combined and back extracted
with 50 ml of CHCl.sub.3. The organic layer from the back
extraction was combined with the organic layer from the washes and
the combined organic layers were dried over Na.sub.2SO.sub.4. The
organic solution was then filtered, concentrated on a rotary
evaporator then was purified via automated flash column
chromatography (0-30% ethylacetate/hexane) to yield 5.37 g of 10 as
a clear light yellow oil.
[0166] .sup.1H-NMR (300 MHz, CDCl.sub.3): .delta. 1.06 (ddd,
J.sub.1=25.3, J.sub.2=12.6, J.sub.3=3.8, 1H), 1.21-1.39 (m, 7H),
1.45-1.60 (m, 3H), 1.65-1.70 (m, 2H), 2.34-2.37 (m, 1H), 2.54-2.69
(m, 2H), 3.04-3.12 (m, 1H), 3.78 (s, 3H), 3.86 (ddd, J.sub.1=42.3,
J.sub.2=13.7, J.sub.3=3.8, 1H), 4.12 (q, J=7.14, 2H), 4.31 (dt,
J.sub.1=56.6, J.sub.2=4.3, 1H), 6.71 (dd, J.sub.1=8.8, J.sub.2=2.2,
1H), 6.82 (d, J=2.7, 1H), 7.00 (apparent t, J=8.2, 1H).
[0167] Synthesis of
(+)-17-ethylcarbamate-3-hydroxy-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(11). In a reaction vessel fit with a stirbar the carbamate 10
(2.43 g, 7.4 mmol) was dissolved in CH.sub.2Cl.sub.2 (20 mL) and
the resulting solution was cooled to 0.degree. C. BBr.sub.3 (9.24
g, 36.9 mmol) was added and the reaction mixture was stirred under
an atmosphere of N.sub.2 at 0.degree. C. for 20 min (at which time
tlc in 20% ethylacetate/hexane showed the reaction to be complete).
A solution of 27% NH.sub.4OH in ice was placed in a beaker with a
stir bar and the reaction mixture was slowly added with stirring.
The resulting mixture was stirred for 20 min then was extracted
with 4:1 CHCl.sub.3/CH.sub.3OH (200 mL). The organic layer was
dried over Na.sub.2SO.sub.4, filtered, then concentrated on a
rotary evaporator. The crude material was purified via automated
flash column chromatography (CH.sub.3OH with 1%
NH.sub.4OH/CHCl.sub.3, 0-10%). The pure fractions were concentrated
on a rotary evaporator to yield 1.48 g of 11 as a white solid.
[0168] .sup.1H-NMR (300 MHz, CDCl.sub.3): .delta. 1.04-1.12 (m,
1H), 1.22-1.36 (m, 7H), 1.45-1.59 (m, 3H), 1.63-1.67 (m, 2H),
2.30-2.33 (m, 1H), 2.52-2.66 (m, 2H), 3.06 (dt, J.sub.1=18.4,
J.sub.2=5.9, 1H), 3.84 (ddd, J.sub.1=35.8, J.sub.2=13.8,
J.sub.3=6.1, 1H), 4.10-4.18 (m, 2H), 4.31 (dt, J.sub.1=53.9,
J.sub.2=3.1, 1H), 6.64 (m, 1H), 6.78 (s, 1H), 6.93 (apparent t,
J=7.8, 1H).
[0169] Synthesis of
(+)-3-(ethoxy-d.sub.5)-17-ethoxycarbonyl-(9.alpha.,13.alpha.,14.alpha.)-m-
orphinan (20). To a solution of alcohol 11 (1.50 g, 4.8 mmol) in
DMF (25 mL), was added K.sub.2CO.sub.3 (2.00 g, 14.5 mmol, 3.05 eq)
and iodoethane-d.sub.5 (1.15 g, 7.1 mmol, 1.50 eq) with stirring.
The reaction mixture was stirred overnight at room temperature (rt)
under an atmosphere of N.sub.2, was quenched by the addition of
H.sub.2O, and extracted with Et.sub.2O (3.times.30 mL). The
combined organics were dried over Na.sub.2SO.sub.4, filtered and
concentrated in vacuo to a yellow oil. Purification via automated
flash column chromatography (0-40% EtOAc/hexanes) afforded
intermediate 20 (1.53 g, 91% yield).
[0170] Synthesis of
(+)-3-(ethoxy-d.sub.5)-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-
-morphinan hydrochloride (100). To a slurry of LiAlD.sub.4 (0.184
g, 4.4 mmol, 2.0 eq) in THF (10 mL) stirring at -78.degree. C. was
added a solution of the carbamate 20 (0.763 g, 2.2 mmol) in THF (5
mL). After 1 h of stirring at rt, no reaction was detected by tlc
and an additional 2.0 eq of LiAlD.sub.4 (0.184 g, 4.4 mmol, 2.0 eq)
was added. The reaction mixture was stirred overnight at rt, then
was quenched by the addition of magnesium sulfate heptahydrate
until cessation of gas evolution. The mixture was filtered,
concentrated in vacuo and the resultant crude material was purified
via automated flash column chromatography
(CHCl.sub.3/CH.sub.3OH/NH.sub.3OH--90/10/1) to yield the free amine
100. This material was dissolved in 1.25 M HCl in CH.sub.3OH then
was concentrated under reduced pressure and dried under high vacuum
to yield 14.3 mg of product 100 as the HCl salt.
[0171] .sup.1H-NMR (300 MHz, DMSO-d.sub.6): .delta. 0.94-1.63 (m,
8H), 1.72-1.80 (m, 1H), 1.94 (d, J=11.9, 1H), 2.43-2.47 (m, 1H),
2.96 (dd, J.sub.1=19.2, J.sub.2=6.1, 2H), 3.09-3.17 (m, 2H),
3.57-3.61 (m, 1H), 6.79-6.82 (m, 2H), 7.11 (d, J=8.8, 1H), 9.58 (br
s, 1H). HPLC (method: 150 mm C18-RP column--gradient method 5-95%
ACN; Wavelength: 280 nm): retention time: 3.08 min, purity: 95%. MS
(M+H): 294.2.
Example 2
Synthesis of
(+)-3-(Ethoxy-d.sub.5)-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
hydrochloride (104)
[0172] Compound 104 was prepared as outlined in Example 1 above
with the exception that LiAlH.sub.4 was used in place of
LiAlD.sub.4 for the reduction of the carbamate 20 to 104.
##STR00013##
[0173] Synthesis of
(+)-3-(ethoxy-d.sub.5)-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
hydrochloride (104). To a slurry of LiAlH.sub.4 (0.166 g, 4.4 mmol,
2.0 eq) in THF (10 mL) stirring at -78.degree. C. was added a
solution of the carbamate 20 (0.763 g, 2.2 mmol) in THF (5 mL).
After 1 h an additional 2.0 eq of LiAlH.sub.4 (0.184 g, 4.4 mmol,
2.0 eq) was added. The reaction mixture was stirred overnight at
rt, then was quenched by the addition of magnesium sulfate
heptahydrate until cessation of gas evolution. The mixture was
filtered, concentrated in vacuo and the resultant crude material
was purified via automated flash column chromatography
(CHCl.sub.3/CH.sub.3OH/NH.sub.3OH--90/10/1) to yield the free-amine
104. This material was dissolved in 1.25 M HCl in CH.sub.3OH then
was concentrated under reduced pressure and dried under high vacuum
to yield 31 mg of product 104 as the HCl salt.
[0174] .sup.1H-NMR (300 MHz, DMSO-d.sub.6): .delta. 0.94-1.64 (m,
8H), 1.74-1.82 (m, 1H), 1.97 (d, J=12.4, 1H), 2.44-2.47 (m, 1H),
2.81 (s, 3H), 2.96 (dd, J.sub.1=20.0, J.sub.2=5.8, 2H), 3.09-3.18
(m, 2H), 3.55-3.62 (m, 1H), 6.79-6.82 (m, 2H), 7.12 (d, J=9.1, 1H),
9.68 (br s, 1H). HPLC (method: 150 mm C18-RP column--gradient
method 5-95% ACN; Wavelength: 280 nm): retention time: 3.00 min,
purity: 95%. MS (M+H): 291.2.
Example 3
Synthesis of
(+)-3-(Isopropoxy-d.sub.7)-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alp-
ha.)-morphinan (102)
[0175] Compound 102 was prepared as outlined below. Details of the
synthesis follow.
##STR00014##
[0176] Synthesis of
(+)-3-(isopropoxy-d.sub.7)-17-ethoxycarbonyl-(9.alpha.,13.alpha.,14.alpha-
.)-morphinan (21)
[0177] To a solution of alcohol 11 (1.50 g, 4.8 mmol; produced
according to Example 1) in DMF (25 mL), was added K.sub.2CO.sub.3
(2.00 g, 14.5 mmol, 3.05 eq) and 2-iodopropane-d.sub.7 (0.71 mL,
7.1 mmol, 1.50 eq) with stirring. The reaction mixture was stirred
overnight at room temperature (rt) under an atmosphere of N.sub.2,
was quenched by the addition of H.sub.2O, and extracted with
Et.sub.2O (3.times.30 mL). The combined organics were dried over
Na.sub.2SO.sub.4, filtered and concentrated in vacuo to a colorless
oil. Purification via automated flash column chromatography (0-40%
EtOAc/hexanes) afforded intermediate 21 (1.48 g, 85% yield).
[0178] Synthesis of
(+)-3-(isopropoxy-d.sub.7)-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alp-
ha.)-morphinan (102). To a slurry of LiAlD.sub.4 (0.340 g, 8.1
mmol, 4.0 eq) in THF (10 mL) stirring at -78.degree. C. was added a
solution of the carbamate 21 (0.739 g, 2.0 mmol) in THF (5 mL). The
reaction mixture was stirred overnight at rt, then was quenched by
the addition of magnesium sulfate heptahydrate until cessation of
gas evolution. The mixture was filtered, the filtrate concentrated
in vacuo and the resultant material was dissolved in CH.sub.3OH.
The resulting solution was acidified to pH 4 with fumaric acid
resulting in salt precipitation. The mixture was stirred for 5 min,
and Et.sub.2O was added to bring remaining salt out of solution.
The salt was isolated by filtration and dried to yield 660 mg of
final product 102 as the fumaric acid salt.
[0179] .sup.1H-NMR (300 MHz, CDCl.sub.3): .delta. 1.10 (qd,
J.sub.1=12.6, J.sub.2=3.8, 1H), 1.21-1.68 (m, 7H), 2.01 (td,
J.sub.1=13.6, J.sub.2=4.5, 1H), 2.16-2.21 (m, 1H), 2.32-2.47 (m,
2H), 2.99-3.01 (m, 2H), 3.10-3.13 (m, 1H), 3.44-3.46 (m, 1H), 6.72
(dd, J.sub.1=8.4, J.sub.2=2.4, 1H), 6.79 (d, J=2.5, 1H), 6.82 (s,
1H), 7.03 (d, J=8.3, 1H). HPLC (method: 150 mm C18-RP
column--gradient method 5-95% ACN; Wavelength: 280 nm): retention
time: 3.11 min, purity: 95%. MS (M+H): 310.3.
Example 4
Synthesis of
(+)-3-(Isopropoxy-d.sub.7)-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morph-
inan (106)
Compound 106 was prepared as outlined in Example 3 above with the
exception that LiAlH.sub.4 was used in place of LiAlD.sub.4 for the
reduction of the carbamate 21 to 106
##STR00015##
[0181] Synthesis of
(+)-3-(isopropoxy-d.sub.7)-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morph-
inan (106). To a slurry of LiAlH.sub.4 (0.308 g, 8.1 mmol, 4.0 eq)
in THF (10 mL) stirring at -78.degree. C. was added a solution of
the carbamate 21 (0.739 g, 2.0 mmol) in THF (5 mL). The reaction
mixture was stirred overnight at rt, then was quenched by the
addition of magnesium sulfate heptahydrate until cessation of gas
evolution. The mixture was filtered, the filtrate concentrated in
vacuo and the resultant material was dissolved in CH.sub.3OH. The
resulting solution was acidified to pH 4 with fumaric acid
resulting in salt precipitation. The mixture was stirred for 5 min,
and Et.sub.2O was added to bring remaining salt out of solution.
The salt was isolated by filtration and dried to yield 330 mg of
final product 106 as the fumaric acid salt.
[0182] .sup.1H-NMR (300 MHz, CDCl.sub.3): .delta. 1.09 (qd,
J.sub.1=12.6, J.sub.2=3.8, 1H), 1.22-1.58 (m, 6H), 1.65 (d, J=12.6,
1H), 2.06 (td, J.sub.1=13.5, J.sub.2=4.3, 1H), 2.20 (d, J=12.4,
1H), 2.35 (d, J=13.3, 1H), 2.46-2.53 (m, 1H), 2.78 (s, 3H),
2.96-3.12 (m, 2H), 3.25-3.30 (m, 1H), 3.62-3.64 (m, 1H), 6.73 (dd,
J.sub.1=8.3, J.sub.2=2.5, 1H), 6.80 (d, J=2.5, 1H), 6.86 (s, 2H),
7.05 (d, J=8.3, 1H). HPLC (method: 150 mm C18-RP column--gradient
method 5-95% ACN; Wavelength: 280 nm): retention time: 3.18 min,
purity: 95%. MS (M+H): 307.4.
Example 5
Synthesis of
(+)-3-(Methyl-d.sub.3)-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(108)
[0183] Compound 108 was prepared as outlined below. Details of the
synthesis are set forth below.
##STR00016##
[0184] Synthesis of
(+)-17-ethylcarbamate-3-trifluoromethylsulfonyloxy-(9.alpha.,13.alpha.,14-
.alpha.)-morphinan (22). To a solution of 11 (9 g, 28.6 mmol, see
Example 1) and triethylamine (16 mL, 114 mmol) in CH.sub.2Cl.sub.2
(400 mL) was added N-phenyl-trifluoromethanesulfonimide
"PhNTf.sub.2" (20.7 g, 57.2 mmol) with cooling in an ice-bath. The
reaction mixture was allowed to warm to ambient temperature and was
stirred overnight. The mixture was diluted with CH.sub.2Cl.sub.2
(500 mL) and the solution was washed with saturated sodium
bicarbonate, water, and brine, then dried over sodium sulfate.
After filtration and concentration under reduced pressure, the
crude product was purified by column chromatography on silica gel
(ethyl acetate/heptanes, 0-10%) to afford 12 g (94%) of 22 as clear
oil.
[0185] Synthesis of
(+)-17-ethylcarbamate-3-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-m-
orphinan (23). To a solution of 22 (22 g, 43.8 mmol) in THF (500
mL) was added N-methyl-2-pyrrolidone "NMP" (26.2 mL, 153.1 mmol) at
ambient temperature. The reaction mixture was degassed by N.sub.2
purge for 10 minutes. Iron(III) acetylacetonate "Fe(acac).sub.3"
(1.65 g, 4.4 mmol) and CD.sub.3MgI (1M in Et.sub.2O, 53 mL, 47.6
mmol, Sigma Aldrich, 99 atom % D) were added and the reaction
mixture was heated to reflux overnight. The reaction was cooled and
water (500 mL) was added. The layers were separated and the aqueous
layer was extracted with CH.sub.2Cl.sub.2 (3.times.100 mL). The
combined organics were washed with brine, dried over sodium
sulfate, filtered, concentrated under reduced pressure and purified
by column chromatography on silica gel (ethyl acetate/heptanes,
0-10%) to afford 4 g (94%, based on recovered starting material) of
23 and 16 g of recovered 22.
[0186] Synthesis of
(+)-3-methyl-d.sub.3)-17-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(108). A mixture of 23 (1.5 g, 4.8 mmol) in THF (70 mL) was treated
with LiAlH.sub.4 (1M in THF, 19.2 mL) at 0.degree. C. The mixture
was allowed to warm to ambient temperature and was stirred
overnight. Water (1 mL) was added to quench the reaction, followed
by NaOH (24%, 10 mL). The mixture was stirred for 30 minutes,
during which time white solid precipitated. The solid was filtered
and the filtrate was concentrated under reduced pressure. The crude
product was purified by preparative HPLC (see conditions described
below) to afford 108. The free amine was dissolved in MTBE (30 mL)
and heated to reflux. H.sub.3PO.sub.4 (in isopropanol) was added
dropwise, resulting in the formation of a white solid. The addition
of H.sub.3PO.sub.4 was continued until no more white solid appeared
to precipitate. The solid was filtered and washed with MTBE (100
mL) to provide 1.2 g of solid. The material was recrystallized with
MeOH/MTBE to provide 108 as the phosphate salt (0.75 g, 47%).
[0187] .sup.1H-NMR (300 MHz, CD.sub.3OD): .delta. 1.07-1.57 (m,
8H), 1.69-1.72 (m, 1H), 1.96-2.10 (m, 2H), 2.56 (br.d., 1H), 2.91
(s, 3H), 3.06-3.11 (br. s. and m, 3H), 3.56 (br.m., 1H), 7.03-7.18
(m, 3H). HPLC (method: 20 mm C-18 RP column--gradient method 2-95%
ACN/water/0.1% formic acid; Wavelength: 210 nm): retention time:
2.59 min, purity: 99.4%. MS (M+H): 259.2
Preparative HPLC conditions: Sunfire C18 Sum 30.times.150 mm
column; Waters GI Pump; Solvent A=water; Solvent B=acetonitrile
Gradient:
TABLE-US-00004 [0188] Time (min) Flow Rate (mL/min) % A % B 0 40.00
90 10 7.00 40.00 50 50 8.00 40.00 5 95 9.00 20.00 90 10 10.00 20.00
90 10
Example 6
Synthesis of
(+)-3-Methyl-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(109)
[0189] Compound 109 was prepared as outlined below. Details of the
synthesis follow.
##STR00017##
[0190] Synthesis of
(+)-17-ethylcarbamate-3-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(24). To a solution of 22 (3.6 g, 7.16 mmol, see Example 5) in THF
(100 mL) was added N-methyl-2-pyrrolidone "NMP" (4.3 mL, 25.1 mmol)
at ambient temperature. The reaction mixture was degassed by
N.sub.2 purge for 10 minutes. Iron(III) acetylacetonate
"Fe(acac).sub.3" (270 mg, 0.72 mmol) and MeMgBr (3M in Et.sub.2O,
2.9 mL, 7.8 mmol) were added and the reaction mixture was heated to
reflux overnight. The reaction was cooled and water (50 mL) was
added. The layers were separated and the aqueous layer was
extracted with CH.sub.2Cl.sub.2 (3.times.100 mL). The combined
organics were washed with brine, dried over sodium sulfate,
filtered, concentrated under reduced pressure, and purified by
column chromatography on silica gel (ethyl acetate/heptanes, 0-10%)
to give 0.84 g of 24 (75% based on recovered starting material) and
2 g of recovered 22.
[0191] Synthesis of
(+)-3-methyl-17-methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-morphinan
(109). A mixture of 24 (1 g, 6.2 mmol) in THF (30 mL) was treated
with LiAlD.sub.4 (0.9 g, 24.8 mmol, Cambridge Isotopes, 98 atom %
D) at 0.degree. C. and the reaction was allowed to warm to ambient
temperature and stir overnight. Water (1 mL) was added to quench
the reaction, followed by NaOH (24%, 5 mL). The mixture was stirred
for 30 minutes, during which time white solid precipitated. The
solid was filtered and the filtrate was concentrated under reduced
pressure. The crude product was dissolved in EtOAc (30 mL) and
extracted with 10% HCl (3.times.30 mL). The combined aqueous layer
was washed with CH.sub.2Cl.sub.2 (30 mL) and neutralized with 10%
NaOH. The aqueous layer was then extracted with CH.sub.2Cl.sub.2
(3.times.30 mL), the combined organics were dried over sodium
sulfate, filtered and concentrated under reduced pressure to afford
109. The free amine was dissolved in MTBE (30 mL) and heated to
reflux. H.sub.3PO.sub.4 (in isopropanol) was added dropwise,
resulting in the formation of a white solid. The addition of
H.sub.3PO.sub.4 was continued until no more white solid appeared to
precipitate. The solid was filtered and washed with MTBE (100 mL).
The product was recrystallized with MeOH/MTBE to provide 109 as the
phosphate salt (0.4 g, 36%).
[0192] .sup.1H-NMR (300 MHz, CD.sub.3OD): .delta. 1.09-1.60 (m,
7H), 1.68-1.71 (m, 1H), 1.98-2.02 (m, 1H), 2.04-2.15 (m, 1H), 2.31
(s, 3H), 2.50-2.55 (m, 1H), 2.64-2.65 (m, 1H), 3.06-3.07 (m, 1H),
3.16 (br.s., 2H), 3.54-3.55 (m, 1H), 7.02-7.17 (m, 3H).
.sup.13C-NMR (75 MHz, CD.sub.3OD): .delta. 20.2, 21.7, 25.8, 35.0,
35.8, 60.3, 125.8, 127.4, 128.0, 130.8, 137.2, 137.4. HPLC (method:
20 mm C18 RP column--gradient method 2-95% ACN/water/0.1% formic
acid; Wavelength: 210 nm):--retention time: 2.51 min. purity:
97.7%. MS (M+H): 259.2.
Example 7
Synthesis of
(+)-3-(Methyl-d.sub.3)-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-
-morphinan (110)
[0193] Compound 110 was prepared as outlined below. Details of the
synthesis follow.
##STR00018##
[0194] Synthesis of
(+)-3-(methyl-d.sub.3)-17-(methyl-d.sub.3)-(9.alpha.,13.alpha.,14.alpha.)-
-morphinan (110). A mixture of 23 (2.5 g, 8 mmol, see Example 5) in
THF (70 mL) was treated with LiAlD.sub.4 (1.7 g, 32 mmol, Cambridge
Isotopes, 98 atom % D) at 0.degree. C. The mixture was allowed to
warm to ambient temperature and was stirred overnight. Water (1 mL)
was added to quench the reaction, followed by NaOH (24%, 10 mL).
The mixture was stirred for 30 minutes, during which time white
solid precipitated. The solid was filtered and the filtrate was
concentrated under reduced pressure. The crude product was purified
by preparative HPLC (see conditions described in Example 5) to
provide 110. The free amine was dissolved in MTBE (50 mL) and was
heated to reflux. H.sub.3PO.sub.4 (in isopropanol) was added
dropwise, resulting in the formation of a white solid. The addition
of H.sub.3PO.sub.4 was continued until no more white solid appeared
to precipitate. The solid was filtered and washed with MTBE (100
mL) to provide 1.2 g of solid. The product was recrystallized in
MeOH/MTBE to provide 110 as the phosphate salt (1 g, 36%).
[0195] .sup.1H-NMR (300 MHz, CD.sub.3OD): .delta. 1.09-1.13 (m,
1H), 1.24-1.33 (m, 1H), 1.39-1.72 (m, 6H), 1.95-2.04 (m, 1H),
2.16-2.18 (m, 1H), 2.50-2.54 (m, 1H), 2.60-2.68 (m, 1H), 3.07-3.16
(m. and s., 3H), 3.54-3.55 (m, 1H), 7.02-7.17 (m, 3H). .sup.13C-NMR
(75 MHz, D.sub.2O): .delta. 21.4, 23.2, 25.5, 25.6, 34.7, 39.3,
43.0, 47.8, 60.4, 126.4, 127.5, 128.3, 131.2, 138.0. HPLC (method:
20 mm C18 RP column--gradient method 2-95% ACN/water/0.1% formic
acid; Wavelength: 210 nm): retention time: 2.61 min., purity
>99.9%. MS (M+H): 262.2.
Example 8
Evaluation of Metabolic Stability in CYP2D6 SUPERSOMEST.TM.
[0196] Human CYP2D6 SUPERSOMES.TM. were purchased from GenTest
(Woburn, Mass., USA). 7.5 mM stock solutions of test compounds
(Compounds 100, 102, 104, 106, dextromethorphan, a deuterated
analog of dextromethorphan wherein each methyl group was replaced
with CD.sub.3 ("d.sub.6-dextromethorphan", chemical name
(+)-3-d3-methoxy-17-d3-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan,
also referred to as Compound 101 in U.S. Ser. No. 12/112,936, and
as "Test Compound" in FIG. 1 and Table 2 below), the ethyl ether
analog of dextromethorphan ("dextroethorphan") or the isopropyl
ether analog of dextromethorphan ("dextroisoproporphan")) were
prepared in DMSO. The 7.5 mM stock solutions were diluted to 50
.mu.M in acetonitrile (ACN). The 1000 pmol/mL CYP2D6 supersomes
were diluted to 62.5 pmol/mL in 0.1 M potassium phosphate buffer,
pH 7.4, containing 3 mM MgCl.sub.2. The diluted SUPERSOMES.TM. were
added to wells of a 96-well deep-well polypropylene plate in
triplicate. 10 .mu.L of the 50 .mu.M test compound was added to the
supersomes and the mixture was pre-warmed for 10 minutes. Reactions
were initiated by addition of pre-warmed NADPH solution. The final
reaction volume was 0.5 mL and contained 50 pmol/mL CYP2D6
SUPERSOMES.TM., 1 .mu.M test compound, and 2 mM NADPH in 0.1 M
potassium phosphate buffer, pH 7.4, and 3 mM MgCl.sub.2. The
reaction mixtures were incubated at 37.degree. C. and 50 .mu.L
aliquots were removed at 0, 5, 10, 20, and 30 minutes and added to
shallow-well 96-well plates which contained 50 .mu.L of ice-cold
ACN with internal standard to stop the reactions. The plates were
stored at 4.degree. C. for 20 minutes after which 100 .mu.L of
water was added to the wells of the plate before centrifugation to
pellet precipitated proteins. Supernatants were transferred to
another 96-well plate and analyzed for amounts of parent remaining
by LC-MS/MS using an Applied Bio-systems API 4000 mass
spectrometer.
[0197] The in vitro half-life (t.sub.1/2) for each of the test
compounds was calculated from the slopes of the linear regression
of % parent remaining (ln) vs incubation time relationship: in
vitro t.sub.1/2=0.693/k, where k=-[slope of linear regression of %
parent remaining(ln) vs incubation time]. Data analysis was
performed using Microsoft Excel Software.
[0198] FIG. 1 and Table 2, below, show the results of the
SUPERSOMES.TM. experiment. Note that in FIG. 1, the curves for
Compounds 100 and 104 overlap one another. "Test Compound" in FIG.
1 and Table 2 refers to deuterated dextromethorphan
("d6-dextromethorphan",
(+)-3-d3-methoxy-17-d3-methyl-(9.alpha.,13.alpha.,14.alpha.)-morphinan,
which is also referred to as Compound 101 in U.S. Ser. No.
12/112,936, incorporated by reference herein).
TABLE-US-00005 TABLE 2 Calculated Half-life in SUPERSOMES .TM..
Compound t.sub.1/2 .+-. SD (min) Dextromethorphan 1.7 .+-. 0.3 Test
Compound 5.6 .+-. 1.5 Dextroethorphan 10.3 .+-. 2.1
Dextroisoproporphan 21.7 .+-. 1.6 Compound 106 36.0 .+-. 2.8
Compound 102 39.0 .+-. 1.9 Compound 104 49.1 .+-. 4.1 Compound 100
51.3 .+-. 3.7
[0199] Each of the deuterated compounds tested demonstrated a
longer half-life when incubated with CYP2D6 SUPERSOMES.TM. than any
of the corresponding undeuterated test compounds or a deuterated
version of dextromethorphan (Test Compound). Thus, in this assay,
the compounds of this invention were more resistant to metabolism
than dextromethorphan or deuterated dextromethorphan (Test
Compound).
Example 9
Determination of Metabolic Stability of Test Compounds using Human
Liver Microsomes
[0200] Human liver microsomes (20 mg/mL) were obtained from
Xenotech, LLC (Lenexa, Kans.). .beta.-nicotinamide adenine
dinucleotide phosphate, reduced form (NADPH), magnesium chloride
(MgCl.sub.2), and dimethyl sulfoxide (DMSO) were purchased from
Sigma-Aldrich.
[0201] 7.5 mM stock solutions of test compounds were prepared in
DMSO. The 7.5 mM stock solutions were diluted to 50 .mu.M in
acetonitrile (ACN). The 20 mg/mL human liver microsomes were
diluted to 1.25 mg/mL (1 mg/mL final) in 0.1 M potassium phosphate
buffer, pH 7.4, containing 3 mM MgCl.sub.2. The diluted microsomes
(375 .mu.L) were added to wells of a 96-well polypropylene plate in
triplicate. 10 .mu.L of the 50 .mu.M test compound was added to the
microsomes and the mixture was pre-warmed for 10 minutes. Reactions
were initiated by addition of 125 .mu.L of pre-warmed NADPH
solution. The final reaction volume was 0.5 mL and contained 1.0
mg/mL human liver microsomes, 1 .mu.M test compound, and 2 mM NADPH
in 0.1 M potassium phosphate buffer, pH 7.4, and 3 mM MgCl.sub.2.
The reaction mixtures were incubated at 37.degree. C., and 50 .mu.L
aliquots were removed at 0, 5, 10, 20, and 30 minutes and added to
shallow 96-well plates which contained 50 .mu.L of ice-cold ACN
with internal standard to stop the reactions. The plates were
stored at 4.degree. C. for 20 minutes after which 100 .mu.L of
water was added to the wells of the plate before centrifugation to
pellet precipitated proteins. Supernatants were transferred to
another 96-well plate and analyzed for amounts of parent remaining
by LC-MS/MS using an Applied Bio-systems API 4000 mass
spectrometer.
7-ethoxy coumarin was used as a positive control.
[0202] The in vitro t.sub.1/2s for test compounds were calculated
from the slopes of the linear regression of % parent remaining (ln)
vs incubation time relationship:
in vitro t.sub.1/2=0.693/k, where k=-[slope of linear regression of
% parent remaining(ln) vs incubation time]
Data analysis was performed using Microsoft Excel Software.
[0203] FIG. 2 (panels A and B), FIG. 3, Table 3, and Table 4 show
the results of this experiment.
TABLE-US-00006 TABLE 3 Calculated Half-life in Human Liver
Microsomes Change over non-deuterated Compound t.sub.1/2 .+-. SD
(min) compound Dextroethorphan 28.3 .+-. 0.6 n/a Compound 104 59.1
.+-. 2.2 109% Compound 100 59.2 .+-. 1.7 109% Dextroisoproporphan
36.1 .+-. 1.6 n/a Compound 106 68.8 .+-. 0.9 91% Compound 102 61.0
.+-. 0.4 69%
[0204] In the case of both dextroethorphan and dextroisoproporphan,
deuteration of the alkyl ether (R.sup.1) resulted in a significant
increase in half life (t.sub.1/2) in human liver microsomes as
compared to the undeuterated counterpart.
TABLE-US-00007 TABLE 4 Calculated Half-life in Human Liver
Microsomes Change over Ave. t.sub.1/2 non-deuterated Compound (n =
2) compound Dimemorfan 23.1 n/a Compound 108 28.0 21% Compound 110
31.6 37%
[0205] In the case of dimemorfan, deuteration of R.sup.1 resulted
in a significant increase in half life (t.sub.1/2) in human liver
microsomes as compared to the undeuterated counterpart. Deuteration
of the N-methyl moiety (R.sup.2) caused a further significant
increase in t.sub.1/2.
[0206] Without further description, it is believed that one of
ordinary skill in the art can, using the preceding description and
the illustrative examples, make and utilize the compounds of the
present invention and practice the claimed methods. It should be
understood that the foregoing discussion and examples merely
present a detailed description of certain preferred embodiments. It
will be apparent to those of ordinary skill in the art that various
modifications and equivalents can be made without departing from
the spirit and scope of the invention. All the patents, journal
articles and other documents discussed or cited above are herein
incorporated by reference.
* * * * *
References