Lignan and phenylpropanoid glycosides from Lancea tibetica and their antitumor activity

A new lignan glucoside, the first 7,9'-monoepoxytetrahydrofuran type lignan with the cis-relationship of H-7 and H-8, named tibeticoside (1), as well as ten known compounds have been isolated from the medicinal plant (roots, stems and leaves) Lancea tibetica. The structure of tibeticoside (1) has be en elucidated on the basis of chemical and spectral evidence, especially by 2D-NMR (H-1-H-1 COSY, HMQC, HMBC, NOESY). In addition, sylvatesmin (6) exh ibited effective antitumor activity on B16 cells.