Stilbenes and oligostilbenes from leaf and stem of Vitis amurensis and their cytotoxic activity.

Chromatographic separation of the EtOAc fraction from the leaf and stem of Vitis amurensis led to the isolation of six oligostilbenoids (i.e., r-2-viniferin (1), trans-amurensin B (2), trans-epsilon-viniferin (3), gnetin H (4), amurensin G (5), (+)-ampelopsin A (8)) and four stilbenoids (i.e., trans-resveratrol (6), (+)-ampelopsin F (7), piceatannol (9), and trans-piceid (10)). The structures have been identified on the basis of spectroscopic evidence and physicochemical properties. The isolates were investigated for cytotoxic activity against three cancer cell lines in vitro using the MTT assay method. Amurensin G (5) and trans-resveratrol (6) showed significant cytotoxic activity against L1210, K562 and HTC116 cancer cell lines with IC(50) values ranging from 15.7 +/- 2.1 to 30.9 +/- 1.8 microM. (+)-Ampelopsin A (8) and trans-piceid (10) exhibited considerable cytotoxic activity against L1210 (IC(50) values of 30.6 +/- 4.1 and 28.7 +/- 2.81 microM, respectively) and K562 (IC(50) values of 38.6 +/- 0.82 and 24.6 +/- 0.76 microM, respectively). Gnetin H (4) showed only weak cytotoxic activity against L1210 with an IC(50) value of 40.1 +/- 4.23 microM. On the other hand, r-2-viniverin (1), trans-amurensin B (2), trans-epsilon-viniferin (3), (+)-ampelopsin F (7), and piceatannol (9) exhibited no activity on three cancer cell lines.