N-[3-nitro(amino)coumarin-4-yl]anthranilic acid amides. Synthesis of 6,7,8,13-tetrahydro[1]benzopyrano[4,3-b][1,4] benzodiazepine-6,8-dione

The reaction of 3-nitro-4-chlorocoumarin with anthranilic acid was used to synthesize N-(3-nitro-4-coumarinyl)-anthranilic acid, from which, through the acid chloride, we obtained a number of amides, which were reduced to N-(3-amino-4-coumarinyl)anthranilic acid amides The latter are cyclized under the influence of hydrochloric acid to 6,7,8,13-tetrahydro1]benzopyrano-4,3-b]1, 4]benzodiazepine-6,8-dione, which was also obtained from N-(3-amino-4-coumarinyl)anthranilic acid by its thermolysis or treatment with hydrochloric acid.See 1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1208–1212, September, 1989.