Synthesis of polyhydroxylated ester analogs of the stilbene resveratrol using decarbonylative Heck couplings

Protected 3,5-hydroxy-benzoyl chlorides 3 were coupled with styrenes 4 to give hydroxylated stilbenes, analogs of resveratrol, an important antioxidant disease preventative agent isolated from grape skins and other dietary sources. Levulinate and chloroacetate protecting groups allowed for the selective production of mono- and di-acetate variations under palladium-N-heterocyclic carbene (NHC) catalyzed decarbonylative coupling conditions. Fluorinated analogs were also produced using Heck conditions with bromofluorobenzenes. Human HL-60 cell assays showed the 4′-acetoxy variant 11 to have improved activity (ED50 17 μM) relative to resveratrol (24 μM).