Patent ID: RE39131

Claim:
A heterocyclic compound of the formula wherein R 1 represents a hydrogen atom or a methyl group, A represents an ethylene group which may be substituted by methyl, X represents an oxygen or sulfur atom or the group in which R 2 represents a hydrogen atom, a C 1 -C 4 alkyl group which may be substituted by a substituent selected from halogens, C 1 -C 4 alkoxy groups, C 1 -C 4 alkylthio groups and cyano, a C 2 -C 4 alkenyl group, a C 2 -C 4 alkynyl group, a pyridylmethyl group which may be substituted by halogen and/or methyl, a benzyl group which may be substituted by halogen and/or methyl, a formyl group, an alkylcarbonyl group having 1 to 2 carbon atoms in the alkyl moiety which may be substituted by halogen, a phenylcarbonyl group which may be substituted by halogen and/or methyl, an alkoxy or alkylthiocarbonyl group having 1 to 4 carbon atoms in the alkyl moiety, a phenoxycarbonyl group, a C 1 -C 4 alkylsulfonyl group which may be substituted by halogen or a phenylsulfonyl group which may be substituted by methyl, R 3 represents a hydrogen atom or a C 1 -C 7 alkyl group, and Z represents a 3-pyridyl group or a 4-pyridyl group optionally substituted by at least one substituent selected from halogen atoms, alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, alkylthio groups having 1 to 4 carbon atoms, haloalkyl groups having 1 to 4 carbon atoms, haloalkoxy groups having 1 to 4 carbon atoms, alkylsulfonyl groups having 1 to 4 carbon atoms, a cyano group and a nitro group.