Synthesis and Antimicrobial Evaluation of some newer symmetrical 1, 4- Dihydropyridines

Abstract

Bacterial resistance is a major drawback in chemotherapy of infectious diseases. In this investigation a new series of 4-(5’-chloro-3’-methyl-1’-N-phenyl-pyrazol4’yl)-2,6-dimethyl-3,5-disubstituted phenyl- carbamoyl-1,4- dihydropyridines (Ia-t) have been synthesized by the cyclocondensation of 5-chloro-3-methyl-1-phenyl-pyrazole-4- carba- ldehyde and N-substituted phenyl)-3-oxobutanamides and ammonia and studied for their enhancing effect on the antibacterial activities towards S. pyogens MTCC-443, S. aureus MTCC-96 and P. aeruginosa MTCC-441(Gram positive) and E. Coli MTCC-442 (Gram negative) bacterial strains and anti fungal activity towards Aspergillus niger MTCC-282 and A. clavatus MTCC-1323 at different concentration for their MIC values using disc diffusion method. During preliminary screening, compounds Ic,Ie,Ig,Ij showed the most enhancing effect on the antibacterial activity as compare to standard drug amoxicillin.The structures of title compounds were elucidated by the IR, NMR and Mass spectrometry and further confirmed by Elemental analyses.