Air stable N-heterocyclic carbene silver complexes: synthesis, characterization, and antibacterial activity

A new benzimidazolium salt containing a 2,5-dimethylbenzyl substituent and six N-heterocyclic carbene (NHC) silver complexes were prepared. The complexes were characterized by NMR, FTIR, and LC-MS spectroscopic methods and elemental analyses. They are stable in solution for a week. The antibacterial properties of the Ag(I) complexes against two Gram-positive and two Gram-negative bacteria were investigated. Inhibition zone and minimum inhibitory concentration (MIC) data establish that these NHC-Ag(I) complexes possess antibacterial activities; 2b showed the highest antibacterial activity overall against Gram-positive and Gram-negative bacteria.

Automated summary

A new benzimidazolium salt containing a 2,5-dimethylbenzyl substituent and six N-heterocyclic carbene (NHC) silver complexes were synthesized and characterized. The stability of the complexes in solution was investigated, and their antibacterial activities against Gram-positive and Gram-negative bacteria were evaluated. Among the complexes, 2b exhibited the highest antibacterial activity overall.