Previous studies on five Gnetum species led to the isolation of about 30 oligostilbenes.It has been reported that several oligostilbenes showed various biological activities [1], [2].such as inhibition of LTB4, C4 [3], [4] and anti-oxidation activities [5].To seek for more potent anti-inflammatory active components and to compare the chemical constituents of different Gnetum species, the chemical constituents of Gnetum cleistostachyum C.Y.Cheng have been investigated and one new stilbenolignans named gnetucleistol F (1), together with eight known compounds gnetofuran A (2),lehmbachol D (3), gnetifolin F (4), gnetumontanin C (5), gnetupendin B, shegansu B, gnetol and daucosterol were obtained.In order to confrim the structures and obtain enough samples for pharmacological test, a biomimetic synthesis route was designed.With ferulic acid or sinapic acid and isorhapontigenin as starting materials, stilbenolignans 1, 2, 3,4 and shegansu B were synthesized by oxidative coupling reaction.Pharmacological test for compounds 1, 2, 3, 4 and 5 indicated that 1-5 possesed moderate inhibition activities on TNF with IC50 of 1.0310-5 mol L-1, 1.0910-5 mol L-1,1.1010-5 mol L-1, 0.9210-5 mol L-1 and 2.4610-5 mol L-1, and compound 1 also showed potent anti-oxidant activity.