title: Analysis of the antioxidant activity of 4-(5-chloro-2-hydroxyphenylamino)-4-oxobut-2-enoic acid derivatives using quantum-chemistry descriptors and molecular docking.
abstract: In the present work, the molecular structure and the antioxidant activity of 4-(5-chloro-2-hydroxyphenylamino)-4-oxobut-2-enoic acid (A) and its derivatives (B-E) have been studied at the B3LYP/6-31++G(2d,2p) computational level. The obtained results indicate that the hydrogen atom transfer (HAT mechanism) is thermodynamically more favored in gas phase; whereas, the sequential proton loss-electron transfer (SPLET mechanism) is more preferred in polar solvents. The antioxidant activity of compounds A-E is also analyzed by the calculation of atomic spin densities, chemical hardnesses, dipole moments, and lipophilicity indexes. It turns out that compound E (R = t-Bu) is predicted to be more antioxidant than ascorbic acid and other derivatives A-D in both gas phase and polar solvents. The high antioxidant activity of compound E compared to other derivatives A-D is also rationalized using the molecular docking technique.
authors.affiliation: Laboratory of Applied Thermodynamics and Molecular Modelling, Department of Chemistry, Faculty of Science, University of Tlemcen, PB 119, Tlemcen, 13000, Algeria.
authors.forename: Ahmed Taki Eddine
authors.initials: AT
authors.lastname: Ardjani
authors.affiliation: Laboratory of Applied Thermodynamics and Molecular Modelling, Department of Chemistry, Faculty of Science, University of Tlemcen, PB 119, Tlemcen, 13000, Algeria. sm_mekelleche@mail.univ-tlemcen.dz.
authors.forename: Sidi Mohamed
authors.initials: SM
authors.lastname: Mekelleche
mesh_terms: D000465:Algorithms; D000814:Aniline Compounds / Q000737:chemistry* / Q000494:pharmacology; D000975:Antioxidants / Q000737:chemistry* / Q000494:pharmacology; D002087:Butyrates / Q000737:chemistry* / Q000494:pharmacology; D020134:Catalytic Domain; D008968:Molecular Conformation; D062105:Molecular Docking Simulation; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D011485:Protein Binding; D011789:Quantum Theory; D013329:Structure-Activity Relationship; D014969:Xanthine Oxidase / Q000737:chemistry / Q000378:metabolism
chemical_list: C000601650:4-(5-chloro-2-hydroxyphenylamino)-4-oxobut-2-enoic acid; D000814:Aniline Compounds; D000975:Antioxidants; D002087:Butyrates; D014969:Xanthine Oxidase
keywords: Antioxidant mechanisms; Carboxylic acids; DFT calculations; Molecular docking; Quantum-chemistry descriptors