An optically active compound represented by the following formula (5): wherein, in the formula (5), R1 and R2 may be the same or different are an alkyl group optionally having a substituent group selected from the group consisting of an alkoxy group and a halogen atom, a cycloalkyl group optionally having a substituent group selected from the group consisting of an alkoxy group and a halogen atom, an aryl group optionally having a substituent group selected from the group consisting of an alkyl group, an alkoxy group and a halogen atom, an alkoxy group optionally having a substituent group selected from the group consisting of a halogen atom and an aryl group or an aryloxy group optionally having a substituent group selected from the group consisting of an alkyl group, an alkoxy group and a halogen atom; a1 and a2 independently are 0 or 1; and * is axial asymmetry.