Ferrocene-substituted 3,3′-diindolylmethanes with improved anticancer activity

A series of ferrocene-substituted derivatives (2a-g) of the known drug 3,3'-diindolylmethane (DIM) were prepared and tested for their in vitro antitumor activity. The derivatives 2a (featuring indole moiety), 2b (featuring 2-methylindole moiety) and 2f (featuring 5-nitroindole moiety) were growth-inhibiting in vitro at lower concentrations than DIM in various tumor cells including pancreas cancer (BcPC-3), three DIM-resistant cancer cell lines (518A2, KB-V1/Vbl, HT-29), triple-negative breast cancer (MDA-MB-231) and prostate cancer (PC-3). Derivatives 2a, 2b and 2f were the most active compounds of this series, qualifying as drug candidates for various cancer diseases. Copyright (C) 2016 John Wiley & Sons, Ltd.