Dimethylbutyrylated Dibenzocyclooctadiene Lignans from the Fruits of Schisandra cauliflora Inhibit NO Production in LPS‐Activated RAW264.7 Cells

From the fruits of Schisandra cauliflora, five new dimethylbutyrylated dibenzocyclooctadiene lignans, named schisandracaurins A−E, were isolated using separation and chromatographic techniques. Their structures were determined by extensive analyses of HR‐ESI‐MS, NMR, and ECD spectra. The schisandracaurins A−E potentially inhibited NO production in LPS‐activated RAW264.7 cells with their IC50 values from 21.4 to 30.3 μM.