Two new stilbenoids, cis-e-viniferin (3) and 2b,14b-dehydro-bisresveratrol (4) were synthesized by photooxida-tion reaction of trans-e-viniferin (2) prepared from trans-resveratrol (1). Pentamethoxyl trans-e-viniferin (5) and pentamethoxyl cis-e-viniferin (6) were also obtained by methylation of trans-e-viniferin (2) with (MeO)2SO2. Their structures were elucidated on the basis of spectral evidence. Compounds 3 and 4 showed potent inhibition of TNF-a at concentrations of 10-5 molL-1 with inhibitory ratios of 51.43% and 36.64%, respectively.
