Activity-guided fractionation of the stem bark of Annona senegalensis
gave four bioactive ent-kaurenoids (1-4). Compound 2 showed selective
and significant cytotoxicity for MCF-7 (breast cancer) cells (ED(50) 1
.0 mu g/mL), and 3 and 4 exhibited cytotoxic selectivity for PC-3 (pro
state cancer) cells but with weaker potencies (ED(50) 17-18 mu g/mL).
The structure of the new compound, 3, was deduced from spectral eviden
ce.