Synthesis and Evaluation of N-Substituted Thiazolidine-2,4-dione Containing Pyrazole as a Potent Antimicrobial Agents

In search of new antimicrobial agents with improved potency, we have synthesized a series of N-substituted thiazolidinedione-pyrazole based 3-(3-(1H-pyrrol-1-yl)propyl)-5-((3-(substituted phenyl)-1-phenyl-1H-pyrazol-4-yl) methylene)thiazolidine-2,4-diones (6a-j) in two successive steps. Initial step involves Knoevenagel type condensation of 3-(substituted phenyl)-1-phenyl-1H-pyrazole-4-carbaldehydes (2a-j) with thiazolidine-2,4-dione (3) to furnish intermediate compounds (4a-j). Finally, target compounds (6a-j) were achieved via one-pot reaction of compounds (4a-j), 1,3-dibromopropane and 1H-pyrrole (5). The chemical structures of all the newly synthesized compounds were established based on IR, 1H NMR, 13C NMR and mass spectra. All the synthesized compounds (4a-j, 6a-j) were evaluated for their in vitro antimicrobial activity.