Organic compounds -- part of the class 532-570 series – Organic compounds – Amino nitrogen containing
Reexamination Certificate
1998-10-09
2004-08-10
Kumar, Shailendra (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Amino nitrogen containing
C564S230000, C564S237000, C514S634000
Reexamination Certificate
active
06774263
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine, N-(2-chloro-5-methylsulfinylphenyl)-1-(7-trifluoromethyl-1,2,3,4-tetrahydroquinolinyl)carboximidamide, and N-(3-methylsulfinylphenyl)-N-methyl-N′-(2-chloro-5-methoxyphenyl)guanidine and pharmaceutically acceptable salts thereof, and pharmaceutical compositions and therapeutic methods of treatment that comprise such compounds (“compounds of the invention”). The compounds of the invention are particularly useful for the treatment or prophylaxis of neurological injury and neurodegenerative disorders.
2. Background
A number of substituted guanidines have been reported. See, e.g., U.S. Pat. Nos. 1,411,731, 1,422,506, 1,597,233, 1,642,180, 1,672,431, 1,730,388, 1,756,315, 1,795,739, 1,850,682, 2,145,214, 2,254,009, 2,633,474, 3,117,994, 3,140,231, 3,159,676, 3,228,975, 3,248,426, 3,252,816, 3,283,003, 3,270,054, 3,301,755, 3,320,229, 3,301,775, 3,409,669, 3,479,437, 3,547951, 3,639,477, 3,681,457, 3,769,427, 3,784,643, 3,803,324, 3,908,013, 3,949,089, 3,975,533, 3,976,787, 4,060,640, 4,014,934, 4,161,541, 4,709,094, 4,906,779, 5,093,525, and 5,190,976; PCT applications WO 90/12575, WO 91/12797, WO 91/18868, WO 92/14697, WO 94/14461, WO 94/27591, WO 95/14467, WO 95/20950, H. W. Geluk, et al.,
J. Med. Chem
., 12:712 (1969), and N. L. Reddy et al.,
J. Med. Chem
., 37:260-267 (1994). WO 94/27591 discloses inter alia N-(2-chloro-5-methylthiophenyl)-N′-(3-methylthiophenyl)-N′-methylguanidine.
Nerve cell death (degeneration) can cause potentially devastating and irreversible effects for an individual and may occur e.g. as a result of stroke, heart attack or other brain or spinal chord ischemia or trauma. Additionally, nerve cell death (degeneration) occurs with neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, Huntington's disease, Amyotrophic Lateral Sclerosis, Down's Syndrome and Korsakoff's disease.
Therapies have been investigated to treat nerve cell degeneration and related disorders, e.g., by limiting the extent of nerve cell death that may otherwise occur to an individual.
The compound MK-801 has exhibited good results in a variety of in vivo models of stroke. See B. Meldrum,
Cerbrovascular Brain Metab. Rev
., 2:27-57 (1990); D. Choi,
Cerbrovascular Brain Metab. Rev
., 2:105-147 (1990). See also Merck Index, monograph 3392, 11th ed., 1989. For example, MK-801 exhibits good activity in mouse audiogenic tests, a recognized model for evaluation of neuroprotective drugs. See, e.g., M. Tricklebank et al.,
European Journal of Pharmacology
, 167:127-135 (1989); T. Seyfried,
Federation Proceedings
, 38(10):2399-2404 (1979).
However, MK-801 also has shown toxicity and further clinical development of the compound is currently uncertain. See J. W. Olney et al.,
Science
, 244:1360-1362 (1989); W. Koek et al.,
J. Phamacol. Exp. Ther
., 252:349-357 (1990); F. R. Sharp et al.,
Society for Neuroscience Abstr
., abstr. no. 482.3 (1992).
It thus would be highly desirable to have new neuroprotection therapies.
SUMMARY OF THE INVENTION
In a first preferred aspect, the present invention provides N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine, and pharmaceutically acceptable salts thereof, i.e. the compound of the following structure (I):
and pharmaceutically acceptable salts thereof. References herein to “compound (I)” refer to the compound of the above structure as well as pharmaceutically acceptable salts of N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine.
The invention also includes optically enriched mixtures of compound (I). As can be seen from the above structure, the sulfur of the 3-methylsulfinyl group is chiral. An optically enriched mixture of compound (I) contains substantially more (e.g. about 60 mole %, 70 mole %, 80 mole % or 90 mole % or more) of one enantiomer than the other enantiomer. For use in the therapeutic methods of the invention, preferably a substantially pure optically active mixture is employed, e.g. a mixture containing at least about 92 mole %, or 95 mole % or even 97 mole %, 98 mole % or 99 mole % or more of one enantiomer of compound (I).
More specifically, the invention includes following optically active (−)-N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine (referred to herein, and shown below as compound (IA)) and (+)-N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine (referred to herein, and shown below as compound (IB)).
Compound (I) (which includes compounds I(A) and/or compound I(B)) has been found to exhibit potent neuroprotective activity. References herein to “compound (I)” are intended to also refer to compound I(A) and/or compound I(B) unless otherwise specified. Those optically active compounds also can be identified as (R)-N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine (referred to herein, and shown below as compound (IA)) and (S)-N-(2-chloro-5-methylthiophenyl)-N′-(3-methylsulfinylphenyl)-N′-methylguanidine, pursuant to the Cahn-Ingold-Prelog convention.
Compound (I) also has been surprisingly found to exhibit significantly decreased untoward behavioral effects in a number of in vivo assays, including Irwin tests and rat rotarod motor coordination tests. See the results of Examples 8 and 9 which follow.
In a further aspect, the invention provides the compound N-(2-chloro-5-methylsulfinylphenyl)-1-(7-trifluoromethyl-1,2,3,4-tetrahydroquinolinyl) carboximidamide, and pharmaceutically acceptable salts thereof, i.e. the compound of the following structure (II):
and pharmaceutically acceptable salts thereof References herein to “compound (II)” refer to the compound of the above structure as well as pharmaceutically acceptable salts of N-(2-chloro-5-methylsulfinylphenyl)-1-(7-trifluoromethyl-1,2,3,4-tetrahydroquinolinyl)carboximidamide.
The invention includes both racemic mixtures and optically enriched mixtures of compound (II). An optically enriched mixture contains substantially more (e.g., about 60 mole %, 70 mole %, 80 mole %, 90 mole % or 95 mole % or 98 mole % or more) of one enantiomer of compound (II) than the other stereoisomer. For use in the therapeutic methods of the invention, preferably a substantially pure optically active mixture is employed, e.g. a mixture containing at least about 92 mole %, or 95 mole % or even 97 mole %, 98 mole % or 99 mole % or more of one enantiomer of compound (II).
In a yet further aspect, the invention provides the compound N-(3-methylsulfinylphenyl)-N-methyl-N′-(2-chloro-5-methoxyphenyl)guanidine, and pharmaceutically acceptable salts thereof, i.e. the compound of the following structure (III):
and pharmaceutically acceptable salts thereof. References herein to “compound (III)” refer to the compound of the above structure as well as pharmaceutically acceptable salts of N-(3-methylsulfinylphenyl)-N-methyl-N′-(2-chloro-5-methoxyphenyl)guanidine.
The invention includes both racemic mixtures and optically enriched mixtures of compound (III). An optically enriched mixture contains substantially more (e.g., about 60 mole %, 70 mole %, 80 mole %, 90 mole % or 95 mole % or 98 mole % or more) of one enantiomer of compound (III) than the other stereoisomer. For use in the therapeutic methods of the invention, preferably a substantially pure optically active mixture is employed, e.g. a mixture containing at least about 92 mole %, or 95 mole % or even 97 mole %, 98 mole % or 99 mole % or more of one enantiomer of compound (III).
It has been found that compounds (I), (II) and (III) are each useful for a number of therapeutic applications. In particular, the invention includes methods for treatment and/or prophylaxis of neurological conditions/injuries such as epilepsy, neurodegenerative conditions and/or nerve cell death (dege
Durant Graham J.
Fischer James B.
Padmanabhan Seetharamaiyer
Perlman Michael
Cambridge Neuroscience Inc.
Edwards & Angell LLP
Hsi Jeffrey D.
Kumar Shailendra
LandOfFree
Pharmaceutically active compound and methods of use does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Pharmaceutically active compound and methods of use, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Pharmaceutically active compound and methods of use will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3307883