Synthesis of [1]Benzopyrano[3,4-c][2]benzazepine-6, 8, 13(7H)-triones

Abstract

Hitherto unknown [1] benzopyrano [3,4-c] [2] benzazepine-6,8,13(7H)-triones (4a-e) have been synthesized by the intramolecular cyclodehydration of N-(2-oxo-2H-1-benzopyran-3-yl) phthalamic acids (3a-e) obtained by the reaction of 3-amino coumarins (1a-e) with phthalic anhydride (2)