New Pyrazoline Derivatives Containing Imine Moiety: Synthesis, Characterization and Antimicrobial Study

Abstract

A new series of pyrazoline derivatives (3-10) have been synthesized and characterized on the basis of FT-IR, 1H-NMR, and Mass techniques. 1-(4-Aminophenyl)-3-(pyridin-4-yl)prop-2-en-1-one (1) as a starting material was prepared by the reaction of 4-aminoacetophenone and 4-pyridinecarboxaldehyde in ethanol, using sodium hydroxide as a catalyst. Pyrazoline derivatives 2 was obtained via the cyclization reaction of compound 1 by the action of hydrazine hydrate 80% in ethanol. The target derivatives (3-8) were obtained by the reaction of pyrazoline derivative (2) with the corresponding aldehyde in ethanol. The novel pyrazoline derivatives 9 and 10 were synthesized by the reaction of pyrazoline derivative 2 with the corresponding anhydride (maleic or phthalic anhydride) in presence of anhydrous sodium acetate in glacial acetic acid. The synthesized derivatives were screened against several bacterial strains: Staphylococcus aureus, Staphylococcus espidermididis, Escherichia coli, Klebsiella and Candida albicans. The synthesized compounds showed promising bio-activity compared with amoxicillin.

Keywords

• chalcone, pyrazoline, schiff base and antimicrobial.