The synthesis of pyranoacridinone inhibitors of protein tyrosine kinases

Abstract

7-Oxo-5,6,7,8-tetrahydroflavone 10 reacts with anthranilonitrile and ethyl anthranilate to give the corresponding enamines, 11 and 13. These enamines undergo base-catalysed cyclization to pyrano[2,3-a]acridin-4-ones, 12 and 14, which undergo oxidation to the fully aromatic systems, 4 and 5. Biological testing of some of these fused heterocyclic systems shows them to have potential in cancer chemotherapy as inhibitors of growth factor-mediated cell proliferation.