Abstract: A pyrimidine derivative represented by the formula (II) or (III): ##STR1## (wherein R.sup.1 and R.sup.2 each represent H, a halogen, amino, nitro, an unsubstituted or substituted alkyl, an alkoxy or an alkoxycarbonyl, or R.sup.1 and R.sup.2 are bonded together to form an unsubstituted or substituted alkylene; R.sup.3 represents an aralkyl or a hetero aromatic ring type-alkyl, R.sup.4 represents H or acyl, R.sup.5 represents H, OH or an alkoxy, R.sup.6 represents H, a halogen, an alkyl or an alkoxy, X represents --CH=, --CH=CH--(CH.sub.2).sub.p --, --CH.sub.2 -- or --CH.sub.2 CH.sub.2 --(CH.sub.2).sub.p --, Y represents =CH-- (CH.sub.2).sub.p --, --CH.sub.2 --(CH.sub.2).sub.p --, a single bond or a double bond, p represents 0 or 1, and . . . represents a single bond or a double bond),and a salt thereof have selective acetylcholinesterase-inhibiting activities and selective A type monoamine oxidase-inhibiting activities, and are useful as an antidepressant and an agent for curing senile dementia.