Abstract: The present invention offers compounds or their salts expressed by formula (I) (in the formula, X indicates an alkyl group, or the like; Y indicates an alkyl group; Z indicates a respectively independent nitro group, or the like; n indicates any integer from 0 to 3; A indicates carbon atom, or the like, and hydrogen atom is bonded thereto in the case where the carbon atom is not substituted with Z; D indicates oxygen atom, or the like; W indicates hydrogen atom, or the like; R1 and R2 indicate respectively independent hydrogen atoms, or the like; R1 and R2 may be bonded, and may form a heterocycle together with the nitrogen atom between R1 and R2).

Abstract: An optically active bisbenzyl compound or a racemic bisbenzyl compound represented by formula (2) that has axial chirality. An optically active azepine derivative or a racemic azepine derivative represented by formula (3). Methods of producing an optically active quaternary ammonium salt compound represented by formula (8).