Synthesis and Antioxidant activity of novel Pyrazoline derivatives

Abstract

Plan: A novel series of pyrazolines were synthesized through chalcones. The synthesized compounds were evaluated for various antioxidant activities. Preface: Pyrazolines belongs to five-membered nitrogen classes of compounds. Pyrazolines were reported with widespread chemotherapeutic activities. Methodology: A new series of Chalcones (2a-j) were prepared by reacting substituted aldehydes and ketones in alcohol medium in presence of NaOH. The chalcones (2a-j) undergoes selective cyclization with benzhydrazide (1) in glacial acetic acid medium to yield the title compounds 1, 3, 5-trisubstituted Pyrazolines (3a-j). The new compounds were assigned on the basis of 1H-NMR, IR and Mass spectral data. The newly synthesized compounds were screened for their In-Vitro antioxidant activity by DPPH, superoxide and nitric oxide methods. Outcome: Some of the tested compounds 3e, 3g, and 3f showed moderate activity when compared to the standard drug ascorbic acid.