The antioxidant effect of imine resveratrol analogues

Twenty five Imine resveratrol analogues (IRAs) were synthesized, replacing the CC bond in resveratrol with CN bond, as well as substitution modifications on aromatic rings. Radical scavenging activities against DPPH, along with singlet oxygen quenching capacities were evaluated, and further confirmed using density functional theory calculations (DFT). It was found that IRAs bearing ortho-OH on B ring have better radical scavenging activities against DPPH than resveratrol, these compounds were also found to be effective 1O2 quenchers. Theoretical studies on the reaction mechanism of these compounds with 1O2 suggest that the 1,3-addition to a double bond with a -OH group with the formation of allylic hydroperoxide is the most probable reaction route.