Examples of substituent that are additionally substituted by the subsituents of X and Y include halogen atom, nitro group, cyano group, alkyl groups such as methyl group, ethyl group and the like; alkoxy groups such as methoxy group and ethoxy group; aryloxy groups such as phenoxy group; aryl groups such as phenyl group and naphthyl group; and aralkyl groups such as benzyl group and phenethyl grou