Daturametelins H, I, and J: Three New Withanolide Glycosides from Datura metel L

Three new withanolide glycosides named daturametelins H–J (1–3), together with two known ones, daturataturin A (4) and 7,27‐dihydroxy‐1‐oxowitha‐2,5,24‐trienolide (5), were isolated from the MeOH extract of the aerial parts of Datura metel L. (Solanaceae). Their structures were determined mainly by spectroscopic techniques including 2D‐NMR (HMBC, HMQC, 1H,1H‐COSY, NOESY) and MS experiments. Compounds 1–5 were tested for their antiproliferative activity towards the human colorectal carcinoma (HCT‐116) cell line. The nonglycosidic compound 5 exhibited the highest activity of the tested withanolides, with an IC50 value of 3.2±0.2 μM (Table 3).