Complete (1)H-NMR and (13)C-NMR spectral analysis of the pairs of 20(S) and 20(R) ginsenosides.
BACKGROUND
Ginsenosides, the major ingredients of Panax ginseng, have been studied for many decades in Asian countries as a result of their wide range of pharmacological properties. The less polar ginsenosides, with one or two sugar residues, are not present in nature and are produced during manufacturing processes by methods such as heating, steaming, acid hydrolysis, and enzyme reactions. (1)H-NMR and (13)C-NMR spectroscopic data for the identification of the less polar ginsenosides are often unavailable or incomplete.


METHODS
We isolated 21 compounds, including 10 pairs of 20(S) and 20(R) less polar ginsenosides (1-20), and an oleanane-type triterpene (21) from a processed ginseng preparation and obtained complete (1)H-NMR and (13)C-NMR spectroscopic data for the following compounds, referred to as compounds 1-21 for rapid identification: 20(S)-ginsenosides Rh2 (1), 20(R)-Rh2 (2), 20(S)-Rg3 (3), 20(R)-Rg3 (4), 6'-O-acetyl-20(S)-Rh2 [20(S)-AcetylRh2] (5), 20(R)-AcetylRh2 (6), 25-hydroxy-20(S)-Rh2 (7), 25-hydroxy-20(S)-Rh2 (8), 20(S)-Rh1 (9), 20(R)-Rh1 (10), 20(S)-Rg2 (11), 20(R)-Rg2 (12), 25-hydroxy-20(S)-Rh1 (13), 25-hydroxy-20(R)-Rh1 (14), 20(S)-AcetylRg2 (15), 20(R)-AcetylRg2 (16), Rh4 (17), Rg5 (18), Rk1 (19), 25-hydroxy-Rh4 (20), and oleanolic acid 28-O-β-D-glucopyranoside (21).
College of Pharmacy, Kangwon National University, Chuncheon, Korea.
Heejung
H
Yang
Greencrosshs, Suntech City, Sungnam, Korea.
Jeom Yong
JY
Kim
Greencrosshs, Suntech City, Sungnam, Korea.
Sun Ok
SO
Kim
Greencrosshs, Suntech City, Sungnam, Korea.
Young Hyo
YH
Yoo
College of Pharmacy and Research Institute of Pharmaceutical Science, Seoul National University, Seoul, Korea.
Sang Hyun
SH
Sung
Panax ginseng; less polar ginsenosides; nuclear magnetic resonance spectroscopy; protopanaxadiol; protopanaxatriol