Library design, synthesis and biological exploration of novel 3,4′-bicarbostyril derivatives as potent antimicrobial, antitubercular and antimalarial agents

Abstract

A library comprises diversely substituted novel 3,4′-bicarbostyril derivatives have been designed by molecular hybridization technique and synthesized via multi-component reaction . Compounds G22 (MIC = 12.5 µg/mL) and G38 (MIC = 25 µg/mL) exhibited 99% inhibition against Mycobacterium tuberculosis, while compounds G40 (IC50 = 0.019 µg/mL) and G20 (IC50 = 0.028 µg/mL) found to have excellent activity against Plasmodium falciparum. Compounds G37 (MIC = 25 µg/mL) and G8, G18, and G38 (MIC = 50 µg/mL) elicited excellent antimicrobial activity compared to standard drugs. Biological results revealed that the potency of the title compounds strongly depends on the length and flexibility of various spacers at N−1, the electronic influence of substituent at R1 and lipophilicity of CH3 group at R2 position on bicarbostyril system.