1,2-malonyl-1,2-dihydrocinnoline derivatives and process for preparation thereof

Novel 1,2-malonyl-1,2-dihydrocinnoline derivatives of Formula I wherein R is a lower alkyl, or phenethyl group, or a phenyl group which may be substituted by a halogen atom, or a hydroxy lower alkyl or lower alkoxy group, R1 is a hydrogen atom, an alkyl group having 2-6 carbon atoms which may be substituted by a halogen atom or hydroxy or lower alkoxy group, or an acyl, cyclopentyl or phenyl group, R2 is hydrogen or a lower alkyl group, and R3 represents one or more optional substituents selected from halogen atoms and lower alkyl groups, and wherein the terms "lower alkyl" and "lower alkoxy" groups means alkyl or alkoxy groups having 1-3 carbon atoms, and the non-toxic, pharmaceutically acceptable salts thereof, are prepared by reacting a 1,2-dihydrocinnoline compound with a malonic acid derivative of formula R1CH(COX)2 in which X represents a halogen atom or an alkoxy group, and, if desired, reacting a resulting product in which R1 is hydrogen, or a metallic salt thereof, with a compound R1-Z in which R1 has the meanings given above other than hydrogen and Z is chlorine, bromine, iodine, -SO4R1 or an anylsulphonate, or, if desired, reacting a resulting product in which R1 is hydrogen with a compound R5 = 0 where R5 represents R1 less a hydrogen atom in the a-position, followed by hydrogenation of the unsaturated compound formed. Pharmaceutical compositions having anti-inflammatory and analgesic and/or anti-pyretic activity which may be administered e.g. orally or parenterally contain as active ingredient a compound of Formula I above or a non-toxic, pharmaceutically acceptable salt thereof.