Theoretical investigation and molecular docking approach on the antioxidant activity of Schiff bases and their tautomers

摘要: A theoretical study of the antioxidant behavior N′-(2-hydroxy-3-methoxy-benzylidene)-4-tert-buty-lenzohydrazide (1), N′-(5-bromo-2-hydroxy-benzylidene)-4-tert-butyl benzohydrazide (2) and N′-(2-hydroxy-3-methoxybenzylidene)-4-methyl-benzene-sulfonohydrazide (3) their tautomers 1 ′ –3 have been carried out at B3LYP/6-31++G(2d,2p). The numerical values descriptors, namely, bond dissociation enthalpy, proton affinity (PA), electron transfer enthalpy (ETE), ionization potential, (PDE) calculated in gas phase media solution (EtOH, DMSO water). obtained results show that hydrogen atom (HAT) mechanism is more favored thermodynamically phase, whereas sequential loss (SPLET) preferred solvents. Moreover, couple (3,3′) found to be most potent as expected experimentally. Furthermore, BDE compound 3 much lower than ascorbic acid (AA), indicating tautomerization compounds 1–3 has great influence on activity these compounds. power (3.3′) was also rationalized by calculation atomic spin density. In addition, molecular docking 1′ –3′ xanthine oxidase (XO) protein target revealed important interactions between active amino acids. predicted a potential inhibitor with higher activity.