Salicylanilide N-monosubstituted carbamates: Synthesis and in vitro antimicrobial activity

The research of innovative antimicrobial agents represents a cutting edge topic. Hence, we synthesized and characterised novel salicylanilide N-monosubstituted carbamates. Twenty compounds were evaluated in vitro against eight bacterial strains and eight fungal species. The lowest minimum inhibitory concentrations (MICs) were found to be <= 0.49 M. Genus Staphylococcus, including methicillin-resistant Staphylococcus aureus, and fungus Trichophyton mentagrophytes showed uniformly the highest rate of susceptibility, whilst Gram-negative bacteria and most of the fungi were less susceptible. A wide range of carbamates provided comparable or superior in vitro antimicrobial activity in comparison to established drugs. Interestingly, extended-spectrum p-lactamase producing strain of Klebsiella pneumoniae was inhibited with MICs starting from 31.25 M. With respect to Staphylococci, 2-[(4-bromophenyl) carbamoyl]-4-chlorophenyl phenylcarbamate exhibited the lowest MIC values (<= 0.98 mu M). 2-[(4-Bromophenyl)carbamoyl]-4-chlorophenyl benzylcarbamate showed the widest spectrum of anti fungal action. The results indicate that some salicylanilide carbamates can be considered to be promising candidates for future investigation. (C) 2016 Elsevier Ltd. All rights reserved.