Summary: | Hydroxide [Ag(OH)L] (L = <sup>IV</sup>L, <sup>V</sup>L, <sup>VI</sup>L, <sup>VII</sup>L), oxide [{AgL}<sub>2</sub>}(μ-O)] (L = <sup>I</sup>L, <sup>II</sup>L, <sup>III</sup>L, <sup>V</sup>L, <sup>VI</sup>L) or chloride [Ag<sup>II</sup>L]Cl, [Ag(<sup>VI</sup>L)<sub>2</sub>]Cl complexes were obtained from reactions of mono- or bicamphorimine derivatives with Ag(OAc) or AgCl. The new complexes were characterized by spectroscopic (NMR, FTIR) and elemental analysis. X-ray photoelectron spectroscopy (XPS), ESI mass spectra and conductivity measurements were undertaken to corroborate formulations. The antimicrobial activity of complexes and some ligands were evaluated towards <i>Candida albicans</i> and <i>Candida glabrata</i>, and strains of the bacterial species <i>Escherichia coli</i>, <i>Burkholderia contaminans</i>, <i>Pseudomonas aeruginosa</i> and <i>Staphylococcus aureus</i> based on the Minimum Inhibitory Concentrations (MIC). Complexes displayed very high activity against the <i>Candida</i> species studied with the lowest MIC values (3.9 µg/mL) being observed for complexes <b>9</b> and <b>10A</b> against <i>C. albicans</i>. A significant feature of these redesigned complexes is their ability to sensitize <i>C. albicans</i>, a trait that was not found for the previously investigated [Ag(NO<sub>3</sub>)L] complexes. The MIC values of the complexes towards bacteria were in the range of those of [Ag(NO<sub>3</sub>)L] and well above those of the precursors Ag(OAc) or AgCl. The activity of the complexes towards normal fibroblasts V79 was evaluated by the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Results showed that the complexes have a significant cytotoxicity.
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