Synthesis, antimicrobial evaluation, and in silico studies of quinoline-1H-1,2,3-triazole molecular hybrids

Antimicrobial resistance has become a significant threat to global public health, thus precipitating an exigent need for new drugs with improved therapeutic efficacy. In this regard, molecular hybridization is deemed as a viable strategy to afford multi-target-based drug candidates. Herein, we report a library of quinoline-1H-1,2,3-triazole molecular hybrids synthesized via copper(I)-catalyzed azide-alkyne [3 + 2] dipolar cycloaddition reaction (CuAAC). Antimicrobial evaluation identified compound 16 as the most active hybrid in the library with a broad-spectrum antibacterial activity at an MIC80 value of 75.39 mu M against methicillin-resistant S. aureus, E. coli, A. baumannii, and multidrug-resistant K. pneumoniae. The compound also showed interesting antifungal profile against C. albicans and C. neoformans at an MIC80 value of 37.69 and 2.36 mu M, respectively, superior to fluconazole. In vitro toxicity profiling revealed non-hemolytic activity against human red blood cells (hRBC) but partial cytotoxicity to human embryonic kidney cells (HEK293). Additionally, in silico studies predicted excellent drug-like properties and the importance of triazole ring in stabilizing the complexation with target proteins. Overall, these results present compound 16 as a promising scaffold on which other molecules can be modeled to deliver new antimicrobial agents with improved potency.