Phytyl Phenolipids: Structurally Modified Antioxidants with Superior Lipid Membrane Interaction

A set of procedures was developed for the simple synthesis of phytyl phenolipids, which resulted in high yields (70-95%) of phytyl esters of caffeic, protocatechuic, homoprotocatechuic, and dihydrocaffeic acids. Initial characterization revealed that these new compounds exhibited similar radical scavenging activity and liposolubility to α-tocopherol, a key antioxidant present in membranes. Cyclic voltammetry analysis indicated that the phytyl derivatives had lower anodic peak potentials compared to the original phenolic acids, with electron transfer following an adsorption-controlled mechanism. In phosphatidylcholine large unilamellar vesicles (LUVs), phytyl esters demonstrated remarkable efficiency in preventing liposome autoxidation when compared to α-tocopherol. Despite their strong radical scavenging capacity and membrane penetration ability, the antioxidant effectiveness of the phytyl esters in liposomes was influenced by the structure of their polyphenolic moiety. These new compounds are considered promising candidates for future pharmacological applications against oxidative stress in lipoproteins and cells, warranting further evaluation of their antioxidant and anti-inflammatory effects in cellular models and in vivo.