Patent ID: 8404691

Claim:
A compound represented by formula (1) or a pharmaceutically acceptable salt thereof: wherein Ar 1 represents a phenyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a cyano group, and a C 1 -C 6 alkyl group; Ar 2 represents a phenyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a C 1 -C 6 alkyl group, and a cyano group; or a pyridyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a C 1 -C 6 alkyl group, and a cyano group; R 1 represents a C 1 -C 6 alkyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a hydroxy group, a C 1 -C 6 alkoxy group, a carbamoyl group, an amino group, a C 1 -C 6 alkanoyl group, and a cyano group; or a C 1 -C 6 alkanoyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a hydroxy group, a C 1 -C 6 alkoxy group, a carbamoyl group, an amino group, and a cyano group; a hydrogen atom; or a hydroxy group; R 2 and R 3 each independently represent a C 1 -C 6 alkyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a hydroxy group, a C 1 -C 6 alkoxy group, a carbamoyl group, an amino group, a C 1 -C 6 alkanoyl group, and a cyano group; a carboxy group; or a hydrogen atom; or R 2 and R 3 may together form an oxo group; or R 2 and R 3 together with the carbon atoms to which R 2 and R 3 are respectively bonded may form a 3- to 5-membered saturated hydrocarbon ring in a spiro form; R 4 represents a C 1 -C 6 alkyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a hydroxy group, a C 1 -C 6 alkoxy group, a carbamoyl group, an amino group, a C 1 -C 6 alkanoyl group, and a cyano group; R 5 represents a C 1 -C 6 alkyl group optionally substituted with one or more substituents each independently selected from a halogen atom, a hydroxy group, a C 1 -C 6 alkoxy group, a carbamoyl group, an amino group, a C 1 -C 6 alkanoyl group, and a cyano group; R 6 represents a halogen atom or a hydrogen atom; and R 7 represents a halogen atom.