The present invention provides a compound represented by the formula (I): wherein ring A is void or a benzene ring optionally having substituent(s), R1 and R2 are each independently a phenyl group optionally having substituent(s), a cyclohexyl group and the like, R3 and R4 are each independently a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group and the like, and X is a residue represented by —OR5 or —NHR6 wherein R5 and R6 are a lower alkyl group optionally having substituent(s), an aralkyl group optionally having substituent(s) and the like, a asymmetric transition metal complex containing the compound as a ligand and a production method of optically active compound using the complex as an asymmetric catalyst.