Patent ID: 8703758

Claim:
A compound represented by formula (I) wherein: R 1 is (1) a group represented by the formula: —COR 2 , wherein R 2 is (a) a C 1-6 alkyl group; (b) a C 1-6 alkoxy group; or (c) an amino group optionally mono- or di-substituted by C 1-6 alkyl group(s); or (2) a 5-membered aromatic heterocyclic group optionally substituted by 1 to 3 substituents selected from a C 1-6 alkyl group; R 3 is a C 1-6 alkyl group optionally substituted by 1 to 3 halogen atoms; R 4 is a hydrogen atom; X is O or CH 2 ; ring A is a 4- to 6-membered nitrogen-containing non-aromatic heterocycle (the heterocycle is optionally crosslinked) or cyclohexane; ring P and ring Q are condensed to form in each of which ring Q is optionally substituted by 1 to 3 halogen atoms; and R 6 is a C 1-6 alkyl group optionally substituted by 1 to 3 substituents selected from the group consisting of a halogen atom and a C 3-6 cycloalkyl group, or a salt thereof.