Withanolides from Physalis minima and their inhibitory effects on nitric oxide production.

Six new withanolides (1-6), including two uncommon 1,10-seco withanolides (1 and 2), together with five known withanolides (7-11), were isolated from the whole plants of Physalis minima Linn.. The structures of new compounds were elucidated through spectroscopic methods, including (1)H, (13)C NMR, 2D-NMR, HRESIMS and circular dichroism (CD). Inhibitory effects of the isolates on nitric oxide (NO) production in lipopolysaccaride-activated RAW264.7 macrophages were evaluated. Compounds 2 and 5 showed strong inhibitory activities with IC50 values of 8.04 and 10.01 μM, respectively. Compounds 1, 9 and 10 exhibited moderate inhibitory activities with IC50 values from 25.54 to 43.58 μM.