Complete 1H-NMR and 13C-NMR spectral assignment of five malonyl ginsenosides from the fresh flower buds of Panax ginseng

Background Ginsenosides are the major effective ingredients responsible for the pharmacological effects of ginseng. Malonyl ginsenosides are natural ginsenosides that contain a malonyl group attached to a glucose unit of the corresponding neutral ginsenosides.