Abstract
A new cucurbitacin with an unusual ring A, isocucurbitacin D 25-O-acetate (1), was isolated from Bolbostemma paniculatum Franguent together with one known compound, cucurbitacin E (2). The structure of new compound was established by spectroscopic methods.
Acknowledgements
The authors give thanks to Wen Li and Yi Sha of the Analytical Centre of Shenyang Pharmaceutical University for recording the 1H NMR, 13C NMR and 2D NMR spectra. We are grateful to Bin Xin, Department of Instrumental Analysis of Institute, Chemistry of Chinese Academy of Sciences, for the HRESI-MS measurement.