Synthesis, and characterization of some Cu(I) complexes having propionitrile and pyridine moieties: An investigation on their antibacterial properties

Abstract

The aim of producing new biologically active compounds lead to the synthesis of some Cu(I) complexes of general formula [Cu(C2H5CN)4][A] and [Cu(C5H5N)4][A] (1–4) {where A: counter anion = B(C6F5)4− and B{C6H3(m-CF3)2}4−} from the reaction of CuCl and silver salt of the corresponding counter anion. The complexes were characterized using elemental analysis, 1H NMR, 11B NMR, FT-IR Spectroscopy, UV–visible spectroscopy and thermo-gravimetric analysis (TGA). The antibacterial activities of all complexes are evaluated by the minimal inhibitory concentration (MIC), using the micro-broth dilution method, against eight bacteria (Gram-negative and Gram-positive), each with fresh clinical isolates. The MIC results were compared with those of Oxytetracycline agent as a positive control. In most cases, the compounds show broad-spectrum activities that were either, more active, or equipotent to, the antibiotic agent in the comparison tests. Complex 4 showed the greatest activity against Proteus mirabilis (Gram- negative) with a minimum inhibitory concentration (MIC) of 8 µg/mL, while complexes 2 and 3 showed the lowest activity against Pseudomonas aeruginosa (Gram-negative) and against Staphylococcus aureus (Gram-positive) with a concentration of 512 µg/mL.

Keywords

• MIC
• Antibacterial
• Cu(I) complexes
• Pyridine
• Propionitrile