Chemical constituents from Lactuca plumieri (L.) Gren. & Godr. (Asteraceae).

This is the first report concerning the natural products of the hitherto unstudied Lactuca plumieri (L.) Gren. & Godr., a member of the tribe Cichorieae (Asteraceae). From aerial parts and roots of this plant, five sesquiterpene lactones and one coumarin were isolated. The compounds were identified as sonchuside A, 11β,13-dihydrolactucin-8-O-acetate, 11β,13-dihydrolactucin, cichorioside B, 11β,13-dihydrolactucin-8-O-acetate-15-O-β-glucopyranoside and coumarin - cichoriin. Their structures were established by 1H NMR. Moreover, HPLC/PAD analysis of a hydroalcoholic extract from the aerial parts of the plant revealed the presence of caffeic acid derivatives, coumarins and flavonoids commonly found in lettuces.