Cucurbitacins from Bryonia cretica

From the roots of Bryonia cretica L. were isolated two new cucurbitacins, isocucurbitacins G (1) and H (2), along with three known cucrbitacins, cucurbitacins G (3), H (4), and J (5). The structures of 1 and 2 were determined on the basis of 1D and 2D NMR spectroscopic analysis and X-ray crystallography. The relative stereochemistries of the side chains of 3-5 were also established by comparison of their NMR data and X-ray crystallography.