An Ecofriendly Synthesis and Biological Evaluation of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic Acid Ethyl Ester Derivatives as an Anti-Tubercular Agents

An ecofriendly route has been investigated for the synthesis of 4-(4-Nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives by one-pot three component condensation of ethyl benzoylacetate, aromatic aldehydes and 2-amino benzimidazole using 260 mol% of citric acid as reaction mediator. Citric acid is an inexpensive, non-toxic and greener medium with smoothly activates the rate of reaction. The synthesized compounds were assessed for in-vitro antimycobacterial activity against Mycobacterium tuberculosis H37RV strain using Microplate Alamar Blue Assay (MABA). The results indicate that, among all the synthesized compound series, P-4 and P-9 compounds illustrate effective activity with MIC 25 µg/ml.