A methanol extract of the dried bark of Liriosma ovata afforded two new isoprenoid glycosides, a eudesmane sesquiterpene, 1alpha(beta- d-glucopyranosyloxy)eudesma-3alpha,4beta, 11-triol ( 1), and a C 13-norisoprenoid, 3alpha,6alpha-dihydroxymegastigman-7-en-9-one 3- O-beta-
Seven new sesquiterpenes (1, 3-8), a new sesquiterpene natural product (2), and two new lignans (9 and 10), together with 15 known compounds, were isolated from the fruits of Xanthium sibiricum. The structures of the new compounds were established by NMR spectroscopic analysis, ECD calculations, and