Abstract

The synthesis of kigelinone thiophene analogs and related naphtho[2,3-b]thiophene-4,9-quinones from 2-substituted 4,7-dimethoxybenzo[b] thiophenes via an oxidative deprotection, Diels-Alder, and oxidative aromatization reaction sequence is reported. The 2-substituted naphtho[2,3-b]thiophene-4,9-quinones display significant antitumor activity in the range IC50 1.1-47 µM on a panel of four distinct human cancer cell lines. © 2009 Bentham Science Publishers Ltd.