In vitro antifungal activities, molecular docking, and DFT studies of 4-amine-3-hydrazino-5-mercapto-1,2,4-triazole derivatives

Abstract

Six disubstituted Schiff base compounds were synthesized (A1-A6) and characterized using infrared spectroscopy (IR), elemental analyses (EA), 1H NMR, 13C NMR and HRMS spectroscopic techniques. Crystal structure of A1 has been determined by single crystal X-ray diffraction. The antifungal activities against three fungi were assessed, and the results showed that compounds of A1 and A2 have good activity for Wheat gibberellic with EC50 value of 15.89 and 16.99 mg/L, respectively. Compounds of A3, A4 and A6 have good bioactivity against Maize rough bacteria (the value of EC50 is 8.23, 7.56 and 7.92 mg/L, respectively). According to the result of molecular docking, compounds of A1 and A2 have the smallest docking energy (-8.33, −9.00 kcal/mol). Besides, for A1 and A2, the analysis of highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) analysis and molecular electrostatic potential map were to further elaborate the reason for the good activity with density functional theory (DFT)-B3LYP/6-31G.