In order to obtain breast tumor directed agents, we have prepared mixed compounds using estradiol or (E)-clomiphene as specific vectors of the breast tissue and a DNA intercalator from the ellipticine series as the cytotoxic agent. Among the newly synthesized ellipticine derivatives, only the 2-[3-aza-5-(3,17 beta-dihydroxy-1,3,5-estratrien-17 alpha-yl)-4-oxopentamethylene]ellipticinium bromide shows the desired properties, DNA intercalation and affinity for estrogen receptor. Competition experiments with estradiol on the hormone-dependent human MCF-7 breast cancer cell line demonstrate that a transport by the estrogen receptor system is not involved in the antitumor activity of derivative 24.

Entsprechend dem Formelschema wird zunächst aus dem Benzophenon (Ia) die Schlüsselverbindung (IVa) dargestellt und, nach Einführung geeigneter Schutzgruppen, mit den Ellipticin‐Derivaten (Va) und (Vb) zu den Verbindungen (VI) umgesetzt.