Synthesis, antitumor screening and cell cycle analysis of novel benzothieno[3,2-b]pyran derivatives.

Three series of benzothiophene derivatives were designed and synthesized as cytotoxic agents. The compounds were subjected to in vitro antitumor screening at the National Cancer Institute (NCI), Bethesda, MD. The results of the single dose screening indicated that only the benzothieno[3,2-b]pyran series 3a-f exhibited potent and broad spectrum cytotoxic activity and was subjected to five dose cytotoxic screening.