Circulatory system-active novel dihydropyrimidines of the formula ##STR1## in which R.sup.1 and R.sup.6 are diverse organic radicals, and pharmacologically acceptable addition salts thereof.
Novel 4-arylpyrimidine derivatives were synthesized by the oxidation of 4-aryl-1, 4-dyhydropyrimidines, and their effects on anti-anoxic (AA) activity in mice and anti-lipid peroxidation (ALP) activity in rat mitochondria were investigated. Among these compounds, ethyl 6-methyl-2-phenyl-4-(4-pyridyl)-5-pyrimidinecarboxylate (4b) has AA activity (10mg/kg, i.p.) and ethyl 6-methyl-4-(3-nitrophenyl)-2-phenyl-5-pyrimidinecarboxylate (4f) has ALP activity (73% inhibition at 10<-5>g/ml). The latter compound (100mg/kg, i.p.) was also effective on arachidonate-induced cerebral edema in rats with comparable potency to that of vitamin E.