New cytotoxic withanolides from Physalis minima.

ABSTRACT

Phytochemical investigation of Physalis minima led to the isolation of six new withanolides, including physaminilides HK (1-4), two artificial withanolides (5-6), and 19 known ones (7-25). Their structures were elucidated on the basis of spectroscopic analysis, including NMR and electronic circular dichroism (ECD) data. The isolates were evaluated for their cytotoxic activities against A375 human melanoma cells. Compounds 1, 8-9, 12-13, 15-17 and 19 exhibited significant cytotoxic activities with IC50 values in the range of 1.2-7.5 µM.