Synthesis, Characterization, and Antioxidant Evaluation of Novel Ethoxylated Pyrazoline Derivatives: Promising Molecules for Drug Design in Pharmaceutical and Chemical Industries

Pyrazolines are the most important class of compounds in the pharmaceutical and chemical industries and (are considered) the most promising molecules for the design of new drugs. In this study, eleven novel ethoxylated pyrazoline derivatives were synthesized by condensing chalcones with an ethoxy group and hydrazine hydrate in the presence of alcohol, highlighting their significance as promising molecules for drug design in the pharmaceutical and chemical industries. The synthesized compounds underwent thorough characterization using 1H NMR, 13C NMR, and mass spectra. Evaluation of these compounds for in vitro antioxidant activity through 2,2’-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide assay methods revealed moderate to good antioxidant properties. Notably, the compound EH2, with a methoxy group, displayed potent antioxidant activity with IC50 values of 9.02 and 9.44µg/ml, while EH9, featuring a hydroxy group, exhibited significant antioxidant activity with IC50 values of 12.41 and 14.56µg/ml in DPPH and hydrogen peroxide assays, respectively, surpassing the standard. Compounds containing electron-donating substituents demonstrated superior antioxidant capabilities compared to the standard ascorbic acid.