A new triterpenoid saponin from Glinus oppositifolius

From the ethanol extract of Glinus oppositifolius, collected at Phu Yen province, Viet Nam, one new triterpenoid saponin (1) and four known compounds (2–5) were isolated. By means of NMR and HR-ESI-MS analyses, their structure was elucidated as 3-O-(β-D-xylopyranosyl-(1→3)-β-D-xylopyranosyl)spergulagenin A or glinusopposide V (1), glinusopposide L (2), spergulin B (3), vitexin (4) and astralagin (5). Two compounds (1–2) showed weak inhibitory activity against α-glucosidase.