Patent ID: 6852744

Claim:
A compound of the formula (I): wherein R 1 is a cycloalkyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a tetrahydronaphthyl group, an indanyl group, a thienyl group, a furyl group, a substituted or unsubstituted indolyl group, a substituted or unsubstituted dihydroindolyl group, a benzofuryl group, a dihydrobenzofuryl group, a substituted or unsubstituted benzothienyl group or an S-mono- or di-oxide thereof, or a dihydrobenzothienyl group, said substituted phenyl, naphthyl and benzothienyl groups having each independently one to three substituents independently selected from a halogen atom, a lower alkoxy group, a hydroxy group and a lower alkyl group having optionally one to three halogen atoms; and said substituted indolyl and dihydroindolyl groups having a substituent on (N) at the 1-position selected from a lower alkyl group and a lower alkyl-carbonyl group; R 2 is a hydrogen atom, an alkyl group, a phenyl-lower alkyl group, a cycloalkyl group or a cycloalkyl-lower alkyl group; R 3 is (i) a substituted or unsubstituted, unsaturated monocyclic heterocyclic group; (ii) a substituted or unsubstituted, saturated or unsaturated monocyclic heterocyclic group which is fused by a benzene ring or a pyridine ring, wherein said substituted heterocyclic groups in (i) and (ii) each independently have one to three substituents independently selected from a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkyl-carbonyl group, a cyano group, a carboxamido group, a phenyl group and a phenoxy group; said phenyl and phenoxy substituents may further optionally have one to three substituents independently selected from a halogen atom, a lower allyl group and a halogeno-lower alkyl group; or (iii) a group of the formula (a): wherein A is a lower alkylene group, D 1 and D 2 are both simultaneously a methylene group or alternatively, one of D 1 and D 2 is a methylene group and another is a vinylene group where each methylene group being optionally substituted by an oxo group or a lower alkyl group, and said vinylene group being optionally substituted by a lower alkyl group; R 6 is a lower alkyl group substituted by a carboxyl group, a lower alkoxycarbonyl group or a phenyl group; R 4 and R 5 are each independently a hydrogen atom or a hydroxy group, but R 4 and R 5 are not simultaneously a hydrogen atom, or both combine to form an oxo group; n is 0, 1, 2 or 3; or a salt thereof.