Complete (1)H-NMR and (13)C-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.


METHODS
Medium-pressure liquid chromatography and semipreparative high-performance liquid chromatography were used to isolate purified compounds and their structures determined by extensive one-dimensional- and two-dimensional nuclear magnetic resonance (NMR) experiments.


RESULTS
A new saponin, namely malonyl-ginsenoside Re, was isolated from the fresh flower buds of Panax ginseng, along with malonyl-ginsenosides Rb1, Rb2, Rc, Rd. Some assignments for previously published (1)H- and (13)C-NMR spectra were found to be inaccurate.


CONCLUSIONS
This study reports the complete NMR assignment of malonyl-ginsenoside Re, Rb1, Rb2, Rc, and Rd for the first time.
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Yu-Shuai
YS
Wang
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Yin-Ping
YP
Jin
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Wei
W
Gao
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China; College of Life Science of Beijing Institute of Technology, Beijing, China.
Sheng-Yuan
SY
Xiao
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Yu-Wei
YW
Zhang
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Pei-He
PH
Zheng
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Jia
J
Wang
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Jun-Xia
JX
Liu
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Cheng-He
CH
Sun
Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agricultural Sciences, Changchun, China.
Ying-Ping
YP
Wang
NMR; Panax ginseng; flower buds; ginsenoside; malonyl ginsenoside Re