Synthesis and antioxidant activity evaluation of new hexahydropyrimido[5,4-c]quinoline-2,5-diones and 2-thioxohexahydropyrimido[5,4-c]quinoline-5-ones obtained by Biginelli reaction in two steps
New hexahydropyrimido[5,4-c]quinoline-2,5-diones and 2-thioxohexahydropyrimido[5,4-c]quinoline-5-ones were prepared in two steps from ethyl 4-phenyl-6-methyl-2-oxo tetrahydropyrimidine-5-carboxylates or 4-phenyl-6-methyl-2-thioxotetrahydropyrimidine-5-carboxylates, previously prepared by Biginelli reaction using appropriate aldehyde, urea derivatives and ethyl acetoacetate. Their antioxidant properties