Synthesis and antibacterial activity of 2-(2,4-dinitrophenyl)-3,5-diphenyl (substituted)-6-aryl-3,3a,5,6-tetrahydro-2H-pyrazolo[3,4-d] thiazoles

Abstract

A series of Schiff's bases have been prepared by condensation of substituted benzaldehydes with primary arylamines and the corresponding 4-thiazolidinones have been prepared by the reaction of Schiff's bases with thioglycolic acid in benzene. The resulting 4-thiazolidinones on reaction with substituted benzaldehydes in anhydrous sodium acetate by Knoevenagel's condensation have afforded 2-phenyl(substituted)-3-aryl-5-benzilidine(substituted) thiazolidine-4-ones, which on cyclization with phenyl hydrazine in anhydrous sodium acetate have furnished the title compounds. The structures have been established on the basis of spectral data. All the compounds have been screened in vitro for their antibacterial activity. The results of antibacterial activity study revealed promising inhibitory activity for 3,3a,5,6-tetrahydro-2H-pyrazolo[3,4-d] thiazole derivatives with 4-chloro and 4-nitro phenyl substitutions at 5-position against all the tested strains.