Two new noroleanane-type triterpenoid saponins from the stems of <i>Stauntonia chinensis</i>

<p>Two new noroleanane-type triterpenoid saponins, 3<i>β</i>,20<i>α</i>,24-trihydroxy-29-norolean-12-en-28-oic acid 24-<i>O</i>-<i>β</i>-L-fucopyranosyl-(1→2)-[<i>β</i>-D-xylopyranosyl-(1→3)]-<i>β</i>-D-glucopyranoside (<b>1</b>) and 3<i>β</i>,20<i>α</i>,24-trihydroxy-29-norolean-12-en-28-oic acid 24-<i>O</i>-<i>β</i>-D-glucopyranosyl-(1→2)-[<i>α</i>-L-arabinopyranosyl-(1→3)]-<i>β</i>-D-glucopyranoside (<b>2</b>) were isolated from the stems of <i>Stauntonia chinensis</i> DC., together with three known compounds, brachyantheraoside B₂ (<b>3</b>), eupteleasaponin Ⅷ (<b>4</b>) and fargoside B (<b>5</b>). Their structures were elucidated by spectroscopic and chemical methods. The cytotoxic activities of compounds <b>1</b> and <b>2</b> were evaluated against five human tumor cell lines (HCT-116, HepG2, BGC-823, NCI-H1650, and A2780). Compounds <b>1</b> and <b>2</b> showed moderate cytotoxic activities toward the tested cell lines with IC₅₀ values ranging from 12.71 to 32.04 μM.