New dammarane-type triterpenoid glycosides from <i>Gynostemma burmanicum</i>

<p>The chemical composition of <i>Gynostemma burmanicum</i> King ex Chakrav. was investigated for the first time in this study. Nine dammarane glycosides (<b>1</b>‒<b>9</b>) were isolated from the EtOH extract of the aerial parts of <i>G. burmanicum</i>. Their structures were elucidated by 1D and 2D NMR spectroscopic interpretation as well as by chemical studies. The new compounds were 3β,20<i>S</i>-dihydroxydammar-24-ene-3-O-β-D-glucopyranosyl-20-O-[β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside] (<b>1</b>), 3β,12β,20<i>S</i>-trihydroxydammar-24-ene-3-O-β-D-xylopyranosyl-20-O-[β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside] (<b>2</b>), and 12-oxo-3β,20<i>S</i>-dihydroxydammar-24-ene-3-O-[β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-[β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside] (<b>3</b>).</p>