. "oatom(s) selected from oxygen, sulfur and nitrogen, etc.), R5 is a hydrogen atom, a C1-6 alkyl group, etc., X is O, S, SO2 or NR6 (R6 is a hydrogen atom, a C1-6 alkyl group or an aryl group), R7 is a hydrogen atom, a C1-6 alkyl group, etc., Y is NR8 or a direct bond (R8 is a hydrogen atom, a C1-6 alkyl group or an aryl group), R9 and R10 are independently a hydrogen atom, a C1-6 alkyl group, etc.," . . . .