Synthesis of Novel Fluorinated 5-Benzylidine-3-ethyl-2-(2,3,4-trifluorophenylimino)thiazolidin- 4-one Derivatives using Knoevenagel Reaction and Evaluation of their in vitro Antimicrobial Potentials

Abstract

A series of novel 5-benzylidine-3-ethyl-2-(2,3,4-trifluoro-phenylimino)-thiazolidin-4-one derivatives were synthesized by Knoevenagel reaction using both conventional as well as non-conventional methods on the synthesized iminothiazolidinone core. The results of an ultrasonic Knoevenagel reaction showed that it was more efficient than the traditional method in terms of yield and reaction time. The compounds were characterized using 1H, 19F and 13C NMR spectra, supported by mass spectrometric and infrared spectroscopic data. The stereochemistry of the final compounds was confirmed using 2D NOESY NMR experiment. The in vitro antibacterial potential of the synthesized benzylidine derivatives were also evaluated. Compounds having trifluoromethyl group on benzylidine moiety were observed to be the most active against the tested bacterial strains as compared to the rest of the compounds.