A new lignan glycoside from the fruits of Cornus kousa Burg.

A new lignan glycoside, (7′S, 8′R)-dihydrodehydrodiconiferyl alcohol-4′-O-β-D-xylopyranoside (1), named cornuskoside A, was isolated from the fruits of Cornus kousa. The structure of the compound was determined by spectroscopy, including FABMS, UV, IR, 1H-and 13C-NMR, DEPT and 2D-NMR (COSY, HSQC, and HMBC). This new lignan glycoside, along with its aglycone, (7′S, 8′R)-dihydrodehydrodiconiferyl alcohol (3), and another lignan with a similar skeleton, (−)-balanophonin (2), which have been previously isolated from this plant, were evaluated for cytotoxicity in human cancer cell lines such as HeLa, MCF-7, SK-MEL-5, and SK-OV-3. Compounds 2 and 3 showed cytotoxicity against HeLa [IC50 = 29.1 μM (2), 45.5 μM (3)], MCF-7 [IC50 = 29.2 μM (2), 28.2 μM (3)], SK-MEL-5 [IC50 = 31.3 μM (2), 32.3 μM (3)], and SK-OV-3 [IC50 = 33.4 μM (2), 43.4 μM (3)] cell lines.