[A new dimeric xanthanolide from fruits of Xanthium chinense].

Through the methods of polyamide resin， Sephadex LH-20， ODS column chromatography and preparative HPLC etc.， 7 compounds were isolated from the 70% ethanol extract of the fruits of Xanthium chinense. Based on ESI-MS and NMR data， the structures of these compounds were identified as pungiolide O(1)， grasshopper ketone(2)， icariside F₂(3)， 7-[(β-D-apiofuranosyl-(1→6)-β-D-glucopyranosyl)oxymethy]-8，8-dimethyl-4，8-dihydrobenzo[1，4]thiazine-3，5-dione(4)，(6R，9S)-3-oxo-α-ionol β-D-glucopyranoside(5)， cryptochlorogenic acid methyl ester(6)， and chlorogenic acid methyl ester(7). Among them， compound 1 is a new compound.