An aminopropylidene derivative having excellent histamine receptor antagonistic action, a compound which is useful as a pharmaceutical composition, especially as an active ingredient, having alleviated side effects in the central nervous system is described. In the aminopropylidene derivative, R1 and R2, which may be identical or different, stand for a hydrogen, a substituted carbonyl, a substituted carbonylalkyl, and acrylic acid, excluding a case where both are hydrogen； R3 and R4, which may be identical or different, stand for hydrogen, an alkyl which may be substituted with phenyl, or the like； A stands for unsubstituted or an oxo； B stands for a carbon or an oxygen； one of X and Y stands for a carbon and the other stands for a sulfur, a broken line part stands for a single bond or a double bond, and a wavy line stands for cis-form and/or trans-form.
