We investigated the reactivity of the Schiff base GO289 2, and 5-bromo-4-formylguaiacol 1 by performing quantum chemical calculations using the density functional theory method. First, we employed this method to predict the reliable orbital molecular energies. Next, we calculated the quantum chemical parameters. Electrophilicity index increases with the various electrodificitary sites of GO289 2. This one is greater than this of 5-bromo-4-formylguaiacol 1. The calculated data confirm that the

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... action of electrons for GO289 2 is large. We have also evaluated the conformations of these molecules in solution using the molecular dynamics simulation. The calculations confirm that the GO289 2 has a spatial conformation state. Molecular dynamic simulations give us very good results in the prediction of reactivity and inhibition effect. Our theoretical results complete very well the experimental data. 03 W programme [19] [20] [21] [22] . The following quantum chemical results are considered: total energy (Et), ionisation potential (IP), energy of the highest occupied molecular orbital (E HOMO ), energy of the lowest unoccupied molecular orbital (E LUMO ), energy gap (EG = E LUMO − E HOMO ), dipole moment (µ), chemical hardness (η), Mulliken electronegativity (χ = − (E LUMO + E HOMO )/2), electrophilicity index (ω = χ 2 /2η), and the fraction of electrons (ΔN). highest interaction energy because of multiple hydrogen bonds with water molecules. We confirm that the combination of the active structure of 1,2,4-triazole with that of substituted phenol has effectively increased the chemical properties and therefore the structure-activity relationship has been demonstrated. We conclude that GO289 2 is a soft Schiff base with high chemical reactivity and strong tendency to adsorb on the metal surface. Our theoretical results complete very well the experimental data of literature.