Synthesis, characterization and antimicrobial activity of new silver complexes with N-heterocyclic carbene ligands

Abstract Synthesis, structure, and antimicrobial studies of silver complexes of N -heterocyclic carbene (NHC) are reported. All the silver–NHC complexes ( 1a–f ) were prepared from the benzimidazolium salts by the reactions with Ag 2 O in dichloromethane as a solvent at room temperature. The new compounds characterized by 1 H NMR, 13 C NMR, IR and elemental analysis techniques which support the proposed structures. Chloro[1-(2,4,6-trimethylbenzyl)-3-(methoxyethyl)benzimidazol-2-ylidene]silver(I) complex was structurally characterized by single-crystal X-ray diffraction. A series of new Ag–NHC complexes were screened for their in vitro antimicrobial activity against a variety of Gram-positive and Gram-negative bacteria as well as for their antifungal activity against a Candida albicans and Candida tropicalis .

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