Abstract: A pharmaceutical composition comprising a pyrimidine represented by the following formula ##STR1## wherein R.sup.1 represents a hydrogen atom, an acyl group having 2 to 4 carbon atoms, an alkoxycarbonyl group having 2 to 5 carbon atoms, an alkoxycarbonylmethyl group having 3 to 5 carbon atoms, a 3,4-dimethoxybenzoyl group or a 3,4-methylenedioxybenzyl group,R.sup.2 represents a hydrogen atom, an amino group, a monoalkylamino group having 1 to 4 carbon atoms, an alkoxy group having 1 to 5 carbon atoms or an alkoxycarbonyl group having 2 to 4 carbon atoms,R.sup.3 represents a hydrogen atom, an alkoxycarbonyl group having 2 to 4 carbon atoms, a dialkylaminocarbonyl group having 1 to 9 carbon atoms in each alkyl moiety, an alkoxy group having 1 to 5 carbon atoms, or a hydroxyethyl group, R.sup.2 and R.sup.3, together with the carbon atoms to which they are bonded, may form a 5- to 7-membered carbocyclic ring or a heterocyclic ring having N, O or S as the hetero atom, and R.sup.