New Triterpenoid Saponins from Green Vegetable Soya Beans and Their Anti-Inflammatory Activities

Ten compounds were isolated and identified from green vegetable soya beans, of which five are new triterpenoid saponins ( 1 – 5 ) and five are known compounds ( 6 – 10 ). The chemical structures of the five triterpenoid saponins ( 1 – 5 ) were elucidated to be 3 β, 24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -xylopyranosyl-(1 → 2)-β- d -glucuronopyranoside, 1; 3 β, 24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -(3″- O -formyl)-galactopyranosyl-(1 → 2)-β- d -glucuronopyranoside, 2; 22-keto-3β,24-dihydroxy oleanane-12-ene 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -(3″- O -formyl)-galactopyranosyl-(1 → 2)-β- d -glucuronopyranoside, 3; 3β,22β,24-trihydroxy oxyolean-18(19)-ene-29-acid 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -galactopyranosyl-(1 → 2)-β- d -glucuronopyranoside, 4; and punicanolic acid 3- O -α- l -rhamnopyranosyl-(1 → 2)-β- d -galactopyranosyl-(1 → 2)-β- d -glucuronopyranoside, 5 from the spectroscopic data (IR, GTC/FID, HR-ESI-MS, and 1D and 2D NMR). The nitric oxide release inhibitions of compounds 1 – 10 in LPS-stimulated RAW264.7 cells were evaluated, and the data suggested that compounds 1, 2, and 5 might possess moderate anti-inflammatory activities, with IC 50 values of 18.8, 16.1, and 13.2 μM, respectively.