An object of the present invention is to provide a novel low molecular weight compound exhibiting an osteogenesis-promoting action. This object is achieved by a compound having the general formula (I) or a pharmacologically acceptable salt thereof:wherein each substituent is defined as follows: R1 represents an alkyl group or the like； R2 represents an alkyl group or the like； R3 represents a hydrogen atom or the like； and Z represents -CH= or -N=.
