Patent ID: 8008525

Claim:
A compound represented by the formula: wherein R a is a fluorine atom, or a C 1-6 alkoxy group R b is a hydrogen atom, or a fluorine atom; R c is a hydrogen atom, or a C 1-6 alkyl group; X a is an oxygen atom; ring C is a benzene ring optionally having, in addition to R d and R e , further substituent(s) selected from the group consisting of (i) a C 1-6 alkyl group, (ii) a hydroxy group, (iii) a C 1-6 alkoxy group having substituent(s) selected from the group consisting of hydroxy, amino, C 1-6 alkoxy-carbonyl-amino, carboxy, C 1-6 alkoxy-carbonyl, carbamoyl, mono-C 1-6 alkyl-carbamoyl, di-C 1-6 alkyl-carbamoyl, and tri-C 1-6 alkylsilyloxy, (iv) a C 6-14 aryloxy group, and (v) a C 7-16 aralkyloxy group; and one of R d and R e is a hydrogen atom, (1) when R d is a hydrogen atom, then R e should be (i) a hydroxy group, (ii) a C 1-6 alkoxy group having substituent(s) selected from the group consisting of C 1-6 alkoxy, carboxy, C 1-6 alkoxy-carbonyl, C 1-6 alkyl-carbonyl, carbamoyl, mono-C 1-6 alkyl-carbamoyl, and di-C 1-6 alkyl-carbamoyl, (iii) a C 2-6 alkynyloxy group, (iv) a C 3-7 cycloalkyloxy group, (v) a C 6-14 aryloxy group optionally having substituent(s) selected from the group consisting of a halogen atom, C 1-6 alkyl, C 1-6 alkoxy, and C 1-6 alkyl-carbonyl, or (vi) a 5- to 10-membered heterocyclyl-oxy group containing, in addition to carbon atom(s), 1 to 4 heteroatoms of one or two kinds selected from a nitrogen atom, a sulfur atom and an oxygen atom; (2) when R e is a hydrogen atom, then R d should be, (i) a C 6-14 aryl group, (ii) a C 3-7 cycloalkyloxy group, (iii) a C 6 - 14 aryloxy group optionally having substituent(s) selected from the group consisting of a halogen atom and optionally halogenated C 1-6 alkyl, (iv) a C 7-16 aralkyloxy group, or (v) a 5- to 7-membered heterocyclic group containing, in addition to carbon atom(s), 1 to 4 heteroatoms of one or two kinds selected from a nitrogen atom, a sulfur atom, and an oxygen atom, or a salt thereof.