A compound represented by the following general formula (I), wherein R1, R2, R3, R4 and R5 represent hydrogen atom, a halo(lower alkyl) group, cyano group and the like, R6 represents an alkyl group, a cycloalkyl group and the like, R7, R8, R9 and R10 represent hydrogen atom, a halogen atom, a lower alkyl group, a halo(lower alkyl) group and the like, R11 and R12 represent hydrogen atom, a lower alkyl group, a (lower cycloalkyl) (lower alkyl) group and the like, and R13 represents hydrogen atom, a halogen atom, a lower alkoxy group and the like, which has potent inhibitory activity on cholesterol ester transfer protein (CETP).