Patent ID: 8318792

Claim:
A method for treating amyotrophic lateral sclerosis, wherein the method comprises administering to a subject in need thereof, an effective amount of a compound represented by the following formula (1), (2) or (3), or a salt thereof: wherein R 1 represents a hydrogen atom, a halogen atom or an amino group; R 2 represents a carboxyl group or a C 1-4 alkoxycarbonyl group; R 3 represents a C 4-6 alkyl group, a C 3-6 cycloalkyl group or a C 3-6 cycloalkyl-C 1-4 alkyl group, all of which are optionally substituted with one to two substituents selected from halogen, hydroxyl, C 1-4 alkoxy, carboxy, C 1-4 alkoxycarbonyl and acyloxy; R 4 represents a pyridyl group which is optionally substituted with one to two substituents selected from halogen, cyano and phenyl; or a phenyl group which is optionally substituted with one to two substituents selected from cyano, nitro, C 1-4 alkoxy, N—C 1-4 alkylpiperazino, C 1-4 alkylthio, phenylthio and C 1-4 alkylamino; R 5 represents a pyridyl group which is optionally substituted with a substituent selected from cyano, C 1-4 alkyl, halogen, C 1-4 alkoxy and C 1-4 alkylthio; R 6 represents a hydrogen atom, or a pivaloyloxy-C 1-4 alkyl group; R 7 represents a carboxyl group, a C 1-6 alkoxycarbonyl group, a carbamoyl group, or a mono- or di-C 1-6 alkylaminocarbonyl group; R 8 represents a hydrogen atom, a C 1-6 alkyl group or a phenyl group; and R 9 represents a hydrogen atom or a C 1-10 alkyl group.