Patent ID: 7723321

Claim:
A compound of the formula (I): or a pharmaceutically acceptable salt thereof, wherein: -A-B— represents —O—CH 2 —, —S—CH 2 —, —CH 2 —O— or —CH2—S—; X represents an oxygen atom or NH; R 1 represents a C 1 -C 6 alkyl group being unsubstituted or substituted with 1 to 2 substituents independently selected from the group consisting of a hydroxy group and a alkoxy group; R 2 and R 3 independently represent a hydrogen atom, a C 1 -C 6 alkyl group, a C 3 -C 7 cycloalkyl group or a heteroaryl group selected from 2-thienyl, 2-thiazolyl, 4-thiazolyl, 2-furyl, 2-oxazolyl, 1-pyrazolyl, 2-pyridyl, 3-pyridyl, 4-pyridyl, 2-pyrazinyl and 2-pyrimidinyl, said C 1 -C 6 alkyl group, said C 3 -C 7 cycloalkyl group and said heteroaryl group being unsubstituted or substituted with 1 to 3 substituents independently selected from the group consisting of a halogen atom, a hydroxy group, a C 1 -C 6 alkoxy group, a C 3 -C 7 cycloalkyl group, an amino group, a C 1 -C 6 alkylamino group, and a di(C 1 -C 6 alkyl)amino group; or R 2 and R 3 taken together with the nitrogen atom to which they are attached form a 4 to 6 membered heterocyclic group being unsubstituted or substituted with 1 to 2 substituents selected from the group consisting of a hydroxy group, a C 1 -C 6 alkyl group, a C 1 -C 6 acyl group and a hydroxy-C 1 -C 6 alkyl group; R 4 , R 5 , R 6 and R 7 independently represent a hydrogen atom, a halogen atom, a hydroxy group, a C 1 -C 6 alkyl group or a C 1 -C 6 alkoxy group; and R 8 represents a hydrogen atom, a hydroxy group or a C 1 -C 6 alkoxy group.