Synthesis of novel benzoxanthone analogues as non-Camptothecin topoisomerase I inhibitors

Abstract

Structure modification of the side chain of the lead compound benzoxanthone provided a series of benzoxanthone analogues and 12 of them were first reported. The results showed that most of these compounds had moderate cytotoxicity against tumour cells with the 50% inhibition concentration in the micromolar range. Furthermore, benzoxanthone derivatives 5, 6c, 7a and 7e, showed potent topoisomerase I (Topo I) inhibitory effect and the results indicated that some compounds had potential for development as non-Camptothecin (CPT) topoisomerase I inhibitors.