[Isolation and identification of malonyl ginsenoside-Ra_1 and malonyl ginsenoside-Ra_2 from fresh roots of Panax ginseng].

The aim of this paper is to study the malonyl ginsenosides in the fresh roots of Panax ginseng. D101 macroporous adsorption resin, ODS, and preparative HPLC were employed to separate the chemical components from the 70% ethanol extract of the fresh roots of P. ginseng, and the structures of the separated compounds were identified based on the data of high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. Two malonyl ginsenosides were isolated from the fresh roots of P. ginseng and identified as 3-O-\[6-O-malonyl-ß-D-glucopyranosyl-(1→2)-ß-D-glucopyranosyl\]-20-O-\[ ß-D-xylopyranosyl-(1→4)-α-L-arabinopyranosyl-(1→6)-ß-D-glucopyranosyl\]-dammar-24-ene-3ß,12ß,20S-triol(1) and 3-O-\[6-O-malonyl-ß-D-glucopyranosyl-(1→2)-ß-D-glucopyranosyl\]-20-O-\[ ß-D-xylopyranosyl-(1→2)-α-L-arabinofuranosyl-(1→6)-ß-D-glucopyranosyl\]-dammar-24-ene-3ß,12ß,20S-triol(2), respectively. Compounds 1 and 2 are new compounds isolated from fresh roots of P. ginseng for the first time and named as malonyl ginsenoside-Ra_1 and malonyl ginsenoside-Ra_2, respectively.