The present invention provides a compound promoting osteogenesis. The present invention provides a compound having the following general formula (I)
wherein R1 is H or alkyl,
R2 is RaS-, RaO-, RaNH-, Ra(Rb)N- or cyclic amino, and
Ra and Rb are alkyl which may be substituted, cycloalkyl which may be substituted, or the like, or a pharmacologically acceptable salt thereof.