Patent ID: 7687502

Claim:
A compound represented by the formula (I): or a pharmaceutically acceptable salt thereof, wherein: X is CH; Y is oxygen atom or sulfur atom; R 1 is one group or atom optionally selected from the following (1), (2), (3), (4), (5) and (6): (1) a five- or six-membered heteroaryl group having one to three hetero atom(s) selected from the group consisting of nitrogen atom, sulfur atom and oxygen atom in a ring, said heteroaryl group (1) being optionally fused to a phenyl ring; (2) an aryl group; (3) a straight-chain or branched lower alkyl group; (4) a cycloalkyl group having 3 to 7 carbon atoms; one of the carbon atoms contained in said group except for a carbon atom bonding to Y, being optionally replaced with an oxygen atom, NH, N-alkanoyl group or carbonyloxy group said R 1 may have one to three groups, being the same or different, selected from α; R 2 is hydrogen atom or fluorine atom; ring A is a monocyclic or bicyclic heteroaryl group represented by the formula (II): said ring A optionally having one to three substituent groups selected from β; substituent group α is selected from the group consisting of: a lower alkyl group optionally substituted with one to three halogen atom(s); a cycloalkyl group having 3 to 7 carbons; a lower alkoxy group; a hydroxyl group; a hydroxyalkyl group; said hydrogen atom of the hydroxyl portion of the hydroxyalkyl group being optionally substituted with a lower alkyl group; an alkanoyl group; halogen atom; oxy group; a lower alkylsulfonyl group; a lower alkylsulfonylamino group; a mono- or di-lower alkylcarbamoyl group; a mono- or di-lower alkylcarbamoylalkyl group; a mono- or di-lower alkylsulfamoyl group; an amino group; a mono- or di-lower alkylamino group; cyano group; and a five- or six-membered heteroaryl group which may have one to three hetero atom(s) selected from the group consisting of nitrogen, sulfur and oxygen; substituent group β is selected from the group consisting of: a lower alkyl group; a lower alkoxy group; a halogen atom; a trifluoromethyl group; a hydroxyalkyl group; wherein the hydrogen atom of hydroxyl group in said hydroxyalkyl group may he substituted with a lower alkyl group; an aminoalkyl group; and wherein the amino group in said aminoalkyl group may be further substituted with a lower alkyl group; an alkanoyl group; carboxyl group; an alkoxycarbonyl group; and a cyano group.