A heterocyclic compound or a salt thereof represented by the formula (1): wherein R2 represents a hydrogen atom or a C1-C6 alkyl group； A represents a C1-C6 alkylene group or a C2-C6 alkenylene group； and R1 represents a C3-C8 cycloalkyl group； wherein at least one group selected from the group consisting of the groups (1) to (66) shown below may be present as a substituent in the C3-C8 cycloalkyl group represented by R1: (1) a group C1-C6 alkyl, (2) a C2-C6 alkenyl group, (3) a halogen substituted C1-C6 alkyl group, (4) a C1-C6 alkoxy group, (5) an aryloxy group, (6) a group C1-C6 alkylthio, (7) a halogen substituted C1-C6 alkoxy group, (8) a hydroxy group, (9) a hydroxy protected group, (10) a hydroxy C1-C6 alkyl group, (11) a group C1-C6 alkyl protected with hydroxy, (12) a halogen atom, (13) a cyano group, (14) an aryl group, (15) a nitro group, (16) an amino group, (17) an amino group having one or more groups selected from the group consisting of a C1-C6 alkyl group, a C1-C6 alkanoyl group, a C1-C6 alkoxycarbonyl group, a C1-C6 alkylsulfonyl group, a carbamoyl group, a C1- alkyl group C6 carbamoyl, an alk group C1-C6 amino noyl, a C1-C6 alkanoyl group C1-C6 amino-alkanoyl and a C1-C6 alkoxycarbonylamino-C1-C6 alkanoyl group as a substituent, (18) a C1-C6 alkanoyl group, (19) a group arylsulfonyl which may have one or more C1-C6 alkyl groups in the aryl group, (20) a carboxy group, (21) a C1-C6 alkoxycarbonyl group, (22) a C1-C6 carboxy alkyl group, (23) an alkoxy group C1-C6 carbonyl-C1-C6 alkyl, (24) a C1-C6 alkanoyl group C1-C6 amino-alkanoyl, (25) a C2-C6 carboxy-alkenyl group, (26) a C1-C6 alkoxy-C2-carbonyl alkenyl group C6, (27) a C2-C6 carbamoyl alkenyl group which may have one or more groups selected from the group consisting of a C1-C6 alkyl group and a halogen substituted C1-C6 alkyl group as a substituent, (28) a carbamoyl group which may have one or more groups selected from the group consisting of groups (i) to (1 xxviii) shown below as a substitu
