Synthesis, properties, and antibacterial activity of a new nitric oxide donor — a nitrosyl iron complex with 5-phenyl-1H-1,2,4-triazole-3-thiol

Abstract

A new binuclear μ-NSC-type nitrosyl iron complex [Fe₂(SR)₂(NO)₄] (R is 5-phenyl-1H-1,2,4-triazole-3-thiolyl) was synthesized. The composition and structure of the newly synthesized complex were determined by atomic absorption, IR, EPR, and Mössbauer spectroscopy and SQUID magnetometry. Amperometric analysis showed that the new complex is an effective nitric oxide (NO) donor in a 1% aqueous DMSO solution. The amounts of NO generated by the complex [Fe₂(SR)₂(NO)₄] in aqueous solutions at physiological pH values were determined. The new complex was shown to have higher antibacterial activity against the gram-positive bacteria Micrococcus luteus compared to kanamycin and streptomycin. According to assays, sulfur-containing ligands of the 1,2,4-triazole-3-thiol series are promising for the design of new antibacterial agents containing the {Fe(NO)₂} structural moiety.