Synthesis of the Hydrazones of 2-((3,5-Di-tert-butyl-4-hydroxybenzyl)thio) acetohydrazide and the Study of their Radical Scavenging Activity by the DPPH Assay and the Computational Method.

The synthesis of antioxidant compounds bearing pharmacologically active groups has become a research interest in the last decade. A series of hydrazones containing a butylated hydroxyl group were synthesized from 2-((3,5-di-tert-butyl-4-hydroxybenzyl)thio)acetohydrazide and various benzaldehyde derivatives, and their radical scavenging activity was explored by 2,2-diphenyl-1-picrylhydrazyl ( DPPH) assay and computational calculations. Based on the results, the effects of different substituents on the DPPH IC50 values were discussed. The bond dissociation enthalpies ( BDE) of OH and NH bonds and the spin density ( SD) values of the compounds were calculated using the density functional theory ( DFT) to determine the theoretical capability of the hydrazones as radical scavengers. Based on the results, the effects of the thioether group and the substituent groups next to the NH bond on the BDE values were also discussed. [ABSTRACT FROM AUTHOR]