[Lignans from flower buds of Magnolia biondii]

The present study aims to investigate the lignans from the flower buds of Magnolia biondii. The isolation and purification of the compounds were performed by column chromatographies on Diaion HP-20, silica gel, and Sephadex LH-20, combined with semi-preparative HPLC. Their structures were elucidated on the basis of spectral data and physiochemical properties. Eighteen compounds were isolated and identified as magnolin (1), epimagnolin (2), eudesmin (3), kobusin (4), aschantin (5), lirioresinol B dimethyl ether (6), pinoresinol monomethy ether (7), (+)-de-O-methylmagnolin (8), isoeucommin A (9), syringaresinol 4-O-β-D-glucopyranoside (10), phillygenin (11), lariciresinol-4'-O-β-1-D-glucoside (12), conicaoside (13), (7'S, 8'R)-dihydrodehydrodiconiferylalcohol (14), 7R*, 8S*-dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside (15), 7S, 8R-erythro-7, 9, 9'-trihydroxy-3, 3'-dimethoxy-8-O-4'-neolignan 4-O-β-D-glucopyranoside (16), 7S, 8R-erythro-4, 9, 9'-trihydroxy-3, 3'-dimethoxy-8-O-4'-neolignan-7-O-β-D-glucopyranoside (17), and (+)-isolariciresinol (18). Compounds 7-18 are isolated from this plant for the first time.