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 (<b>1</b>–<b>5</b>) and five are known compounds (<b>6</b>–<b>10</b>). The chemical structures of the five triterpenoid saponins (<b>1</b>–<b>5</b>) were elucidated to be 3<i>β,</i>24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3-<i>O</i>-α-l-rhamnopyranosyl-(1 → 2)-β-d-xylopyranosyl-(1 → 2)-β-d-glucuronopyranoside, <b>1</b>; 3<i>β,</i>24-dihydroxy-22β,30-epoxy-30-oxoolean-12-en 3-<i>O</i>-α-l-rhamnopyranosyl-(1 → 2)-β-d-(3″-<i>O</i>-formyl)-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, <b>2</b>; 22-keto-3β,24-dihydroxy oleanane-12-ene 3-<i>O</i>-α-l-rhamnopyranosyl-(1 → 2)-β-d-(3″-<i>O</i>-formyl)-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, <b>3</b>; 3β,22β,24-trihydroxy oxyolean-18(19)-ene-29-acid 3-<i>O</i>-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, <b>4</b>; and punicanolic acid 3-<i>O</i>-α-l-rhamnopyranosyl-(1 → 2)-β-d-galactopyranosyl-(1 → 2)-β-d-glucuronopyranoside, <b>5</b> from the spectroscopic data (IR, GTC/FID, HR-ESI-MS, and 1D and 2D NMR). The nitric oxide release inhibitions of compounds <b>1</b>–<b>10</b> in LPS-stimulated RAW264.7 cells were evaluated, and the data suggested that compounds <b>1</b>, <b>2</b>, and <b>5</b> might possess moderate anti-inflammatory activities, with IC₅₀ values of 18.8, 16.1, and 13.2 μM, respectively