New lignan, benzofuran, and sesquiterpene derivatives from the roots of Leontopodium alpinum and L-leontopodioides

Three new compounds, including a benzofuran,1-[(2R*,3S*)-3-(beta-D-glucopyranosyloxy)-2,3-dihydro-2-[1-(hydroxymethyl)vinyl]-1-benzofuran-5-yl}ethanone (1), a lignan, [(2S,3R,4R)-4-(3,4-dimethoxybenzyl)-2-(3,4-dimethoxyphenyl)tetrahydrofuran-3-yl]methyl (2E)-2-methylbut-2-enoate (2), and a silphiperfolene-type sesquiterpene, [(1S,2Z,3aS,5aS,6R,8aR)-1,3a,4,5,5a,6,7,8-octahydro-1,3a,6-trimethylcyclopenta[e]pentalen-2yl]methyl acetate (3), together with the known coumarins obliquin (4) and its 5-methoxy derivative 5 were isolated from the roots of Leontopodium alpinum. Another known coumarin derivative, 5-hydroxyobliquin (6), was isolated from the roots of L. leontopodioides. The structures of these compounds were established by spectroscopic studies.