Cytotoxic withanolides from Physalis angulata L.

Four new withanolides, physagulins L-O (1-4), were isolated from the MeOH extract of the aerial parts of Physalis angulata L. (Solanaceae), together with seven known withanolides, compounds 5-11.. Their structures were determined by spectroscopic techniques, including H-1-, C-13-NMR (DEPT), and 2D-NMR (HMBC, HMOC, H-1,H-1-COSY, NOESY) experiments, as well as by HR-MS. All eleven compounds were tested for their antiproliferative activities towards human colorectal-carcinonla (HCT- 116) and hurnan non-small-cell lung-cancer (NCI-H460) cells. Cornpound 5 exhibited the highest anticancer activity against the HCT-116 cell line, with an IC50 value of 1.64 +/- 0.06 mu m. Compound 9 exhibited the highest cytotoxicity towards the NCI-H460 cell line, with an IC50 value of 0.43 +/- 0.02 mu m (Table 3).