Synthèse, réduction chimique et électrochimique de benzopyranno[1][4,3-e] et [3,4-e]pyrimido[1,2-b]-as-triazinones

Les amino-2 et -3 9H-benzopyranno[1][4,3-e] et [3,4-e]-as-triazines reagissent avec les β-cetoesters ce qui donne des benzopyranno[1][4,3-e] et [3,4-e]pyrimido[1,2-6]-as-triazinones-1 ou 4. Ces nouveaux heterocycles sont reduits en dihydro ou tetrahydrotriazinones, selon l'agent reducteur. From 9H-amino [l]benzopyranno-as-triazines 2 and 3, [l]ben-zopyranno[4,3-e] or [3,4-e]pyrimido[l,2-b]-as-triazinones have been prepared by reaction with β-ketoesters. Chemical reduction of the compounds gives tetrahydro derivatives. By electrochemical reduction the dihydro compounds 14 and 15 were from-ed. The same dihydro derivatives were obtained with Grignard reagents.