Patent ID: 7829586

Claim:
A compound of the formula (I): wherein: A 1 , A 2 and A 3 are the same or different, each representing a carbon atom or a nitrogen atom, provided that at least one of A 1 , A 2 and A 3 is a carbon atom, and at least one of A 1 , A 2 and A 3 is a nitrogen atom; R 1 represents a halogen atom, a C 1-6 alkyl group which is unsubstituted or substituted with a C 1-6 alkoxy group, or a phenyl group substituted with a halogen atom; R 2 represents a phenyl group which is unsubstituted or substituted with a halogen atom or a C 1-6 alkyl group; a pyridinyl group which is unsubstituted or substituted with a halogen atom or a C 1-6 alkyl group; or a thiazolyl group which is unsubstituted or substituted with a halogen atom or a C 1-6 alkyl group; R 3 represents a hydrogen atom; a C 1-6 alkyl group which is unsubstituted or substituted with a hydroxyl group, a halogen atom, a C 1-6 alkoxy group or a cyano group; or a C 3-6 cycloalkyl group which is unsubstituted or substituted with a hydroxyl group or a halogen atom; R 4 represents a C 1-6 alkyl group; a C 3-6 cycloalkyl group which is unsubstituted or substituted with a halogen atom, a hydroxyl group or a C 1-6 alkoxy group; a C 3-6 cycloalkyl-C 1-6 alkyl group which is unsubstituted or substituted with a halogen atom, a hydroxyl group or a C 1-6 alkoxy group; or a tetrahydro-2H-pyran-4-yl group; or a pharmaceutically acceptable salt thereof.