Four New Stilbene Derivatives Isolated from Gnetum latifolium var. funiculare Markgr. and Their Inhibition of NO Production in LPS‐activated RAW264.7 Cells

Abstract Gnetum latifolium var. funiculare Markgr. is a medicinal plant and widely distributed in mountainous areas of Vietnam. Phytochemical investigation on the trunks of this plant afforded eight stilbene derivatives ( 1 – 8 ) including for new compounds ( 1 – 4 ). Their structures were determined based on extensive analyses of HR‐ESI‐MS, 1D and 2D NMR spectra. Among the isolates, compounds 1 – 3 showed moderate NO production inhibition in LPS‐activated RAW264.7 cells with the IC 50 values ranging from 46.81 to 68.10 μM, compounds 4 and 6 showed weak effects with the IC 50 values of 96.57 and 79.46 μM, respectively, compared to that of the positive control compound, dexamethasone (IC 50 14.20 μM).