Labdanes and withanolides from Physalis coztomatl

Aerial parts of Physalis coztomatl afforded a new labdane diterpene, physacoztomatin (1), and five new withanolides, physacoztolides A-E (5-9). Six known compounds were also isolated. The structures of the new compounds were established after analyses of their spectroscopic data and by means of chemical transformations. X-ray diffraction analyses of 15-dehydrophysacoztomatin (2) and 5 confirmed the structures of 1 and 5. Labd-13(E)-ene-8alpha,15-diol (4) and physacoztomatin (1) represent the first labdane diterpenes isolated from the genus Physalis.