Antioxidant activity of some phenolic aldehydes and their diimine derivatives: A DFT study.

Phenolic compounds are known as antioxidant and/or radical scavengers via H-atom transfer or single electron transfer pathway. Density functional theory (DFT) calculations have been performed on some phenolic aldehydes and some of their designed diimine derivatives with different spacer lengths. Both H-atom transfer and single electron transfer pathways have been investigated by calculating the phenolic O–H bond dissociation energy (BDE) and vertical ionization potentials (IP V ). Moreover, the polarity of the solvent medium has been included in calculating BDE and IP V . The radical scavenging activity of these derivatives has been compared with 1,1-diphenyl-2-picrylhydrazyl (DPPH ) free radical. [ABSTRACT FROM AUTHOR]