Utility of 5-antipyrylazo pyridin-2-one derivatives: Syntheis of 5-antipyrylazo pyridinthione and 5-antipyrylazo isoquinoline derivatives

Pyridinone derivatives 1(a-c) were prepared through reaction of 3-antipyrylazo- pentan -2,4-dione with cyanoacetamide, cyanothioacetamide and cyanoacetanilide respectively. Compounds 1(a-c) underwent Michael type addition reaction with alpha,beta -unsaturated nitriles (9,10,11 and 12) in basic medium to afford 4-antipyrylisoquinoline derivatives 2(a-c), 5(ac), 7(a-c) and 8(a-c) respectively. Also compound 1(a-c) could be condensed with benzaldehydes to give benzylidene derivatives 3(a-c). Compounds 3(a-c) were reacted with malononitrile, ethylcyanoacetate and benzoylacetonitrile to give isoquinoline derivatives 2(a-c), 5(ac) and 8(a-c) respectively. Structures of the products were confirmed on the basis of the elemental analysis and spectral data.