On the chemistry of cinnoline IV [1]. Synthesis and reactions of (4-aminocinnolin-3-yl)-aryl-methanones

The synthesis of a series of disubstituted (4-aminocinnolin-3-yl)-aryl-meth anones from aryl-hydrazonomalononitrile in a one-step procedure is describe d. Cyclocondensation of (4-amino-6,8-dimethyl-cinnolin-3-yl)-phenyl-methano ne with malononitrile, diethylmalonate, and dimethylacetamide-dimethylaceta l gave the corresponding pyrido[3,2-c]cinnoline derivatives. Treatment of ( 4-amino-6,8-dimethyl-cinnolin-3-yl)-phenyl-methanone with triethyl-orthoace tate under reflux readily afforded the corresponding imidoester which under went cyclization to a pyrido[3,2-c]cinnoline derivative. This starting comp ound could also be annelated to the corresponding 1,2-dihydro-4-aryl-2-oxo- pyrido[3,2-c]cinnoline derivatives via the (4-acetamidocinnolin-3-yl)-aryl- methanones. Chemical and spectroscopic evidences for the structures of the new compounds are presented. The effect of three of the compounds against s ixty cancer types was tested.