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Updated: Aug 8, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Proton dissociation is important to understanding structure-activity relationships of gallic acid antioxidants
Hong-Fang Ji1, Hong-Yu Zhang, Liang Shen
1Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Center for Advanced Study, Shandong University of Technology, Zibo 255049, PR China.
Abstract:
Gallic acid derivatives (GADs) can efficiently scavenge free radicals, which is partially responsible for their neuroprotective effects. As GADs tend to deprotonate to give birth to GAD anions, which has big influence on the radical-scavenging behaviors of GADs, to understand the structure-activity relationships (SARs) of GAD antioxidants, the anions should be taken into consideration. In this paper, a combined density functional theory method, labeled as (RO)B3LYP/6-311+G(2d,2p)//AM1/AM1, was employed to calculate homolytic O-H bond dissociation enthalpies and adiabatic ionization potentials for GADs and derived anions in solvent (ethanol), by which the experimentally observed SARs of GADs were better elucidated.
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