Dibenzocyclooctadiene lignans from the root bark of Schisandra sphenanthera

Two new dibenzocyclooctadiene lignans, schisphenlignan M and N (1 and 2), together with nine known analogues, schisantherin B (3), gomisin G (4), schisantherin D (5), schisantherin A (6), epigomisin O (7), gomisin O (8), (+)-gomisin K3 (9), schisanhenol B (10) and gomisin A (11) were isolated from the 80 % ethanol extract of root bark of Schisandra sphenanthera. Their structures were determined on the basis of spectroscopic analysis including IR, HR-ESI-MS, 1D and 2D NMR and CD spectra data. Compounds 1-11 were evaluated for their cytotoxic activity against human lung cancer cell line A549, and human colon cancer cell lines HTC116 and SW620, and the results showed that all of the lignans, except 3 and 8 (>50 mu M), exhibited cytotoxic activities with IC50 values ranging from 13.5 to 48.8 mu M.

Automated summary

Two new dibenzocyclooctadiene lignans, schisphenlignan M and N, along with nine known analogues, were isolated from the root bark of Schisandra sphenanthera. These lignans showed cytotoxic activities against human lung and colon cancer cell lines, indicating potential anti-cancer properties.