Revealing the Antioxidant Properties of Alkyl Gallates: A Novel Approach through Quantum Chemical Calculations and Molecular Docking

Abstract

This study investigates the antioxidant properties of alkyl gallates (C1-C10) through quantum chemical calculations and molecular docking methods. Density functional theory (DFT) was employed to calculate key thermochemical parameters such as bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), proton affinity (PA), and electron transfer enthalpy (ETE) in both gas and solvent phases (benzene, ethanol, and water). The results indicate that the alkyl chain length and the solvent environment significantly influence the antioxidant activity of alkyl gallates. BDE values demonstrate that the hydrogen atom transfer (HAT) mechanism is preferred in the gas phase due to its relatively consistent BDE values and strong correlation with spin density distributions. Conversely, the SET-PT and SPLET mechanisms are more efficient in polar solvents, as indicated by significant reductions in IP, PDE, PA, and ETE values. Molecular docking studies with Tyrosine kinase Hck, Heme Oxygenase, and Human Serum Albumin reveal how structural changes in the alkyl chain influence binding interactions, guiding the synthesis of new compounds with enhanced antioxidant activity. The computational findings, which align well with experimental data, underscore the importance of considering both molecular structure and solvent effects in evaluating the antioxidant potential of alkyl gallates. This integrated approach highlights the critical interplay between computational predictions and experimental validations in advancing antioxidant research.