Polycyclic aromatic alkaloids. XII: In vitro- and in vivo-investigations of the cytotoxic marine alkaloid 2-bromoleptoclinidinone.

Aminoquinone 2a, the tetracyclic quinone 3b, and the pentacyclic alkaloid 2-bromoleptoclinidinone (4a) were submitted to the NCl standard in vitro assay using 60 tumor cell lines. Compound 4a showed very high in vitro cytotoxicity and was therefore selected for further evaluation. In the in vivo screening 4a was tested at maximally tolerated doses in four models, but no significant antitumor activity could be found.