Regioselective biomimetic oxidation of halogenated resveratrol for the synthesis of (±)-ε-viniferin and its analogues

Abstract

FeCl3·6H2O-promoted biomimetic oxidations of 3,5-dihalogeno-resveratrol in different acetone systems produced several coupling intermediates bearing distinct dimeric skeletons with moderate yields. The subsequent deprotection reactions of brominated coupling products achieved the efficient synthesis of natural products (±)-ε-viniferin, (±)-ampelosin B, and (±)-gnetins F, as well as an unnatural oligostilbene. The coupling mechanisms for the formation of different dimeric structures were also proposed.