Silver complexes of ligands derived from adamantylamines: Water-soluble silver-donating compounds with antibacterial properties

摘要

Two new silver(I) complexes, namely [Ag(qyAm)2](CF3SO3) (>1) and [Ag(qyTAm)2](CF3SO3) (>2), (qyAm = 2-(quinonyl)iminoadamantane, qyTAm = 2-(quinonyl)iminotriazaadamantane) have been synthesized and characterized by elemental analyses, ¹H NMR, IR, electronic absorption spectroscopy, and X-ray diffraction. The coordination geometry of the silver center in both complexes is distorted tetrahedral where their respective qyAm and qyTAm ligand bind in a bidentate fashion using the imine and quinoline nitrogen atoms. Complex >2 is soluble in water and exhibits strong antimicrobial actions on both Gram-negative (E. coli, and P. aeruginosa) and Gram-positive (S. aureus) bacteria. The minimal inhibitory concentration (MIC) values for complex >2 (4, 4, and 8 μg for E. coli, P. aeruginosa, and S. aureus, respectively) are comparable to MIC values of silver nitrate and silver sulfadiazine.