Synthesis of novel ferrocene containing vic-dioxime ligands and their Ni(II), Cu(II) and Co(II) complexes: Spectral, electrochemical and biological activity studies

Two new vic-dioxime ligands bearing an important redox-active substituent, anti-β-ferrocenylethylaminoglyoxime (1a) and anti-β-ferrocenylethylaminophenylglyoxime (1b), have been synthesized, and their Ni(II), Cu(II) and Co(II) (2a-4a, 2b-4b) complexes were obtained. The composition and structure of the products were determined by elemental analysis, Fourier transform infrared (FT-IR), ultraviolet–visible (UV–vis), mass spectrometry (MS), one-dimensional (1D) 1H, 13C NMR, and two-dimensional (2D) heteronuclear multiple bond correlation (HMBC) techniques. The redox behaviors of the ligands and their complexes were investigated by cyclic voltammetry (CV), which revealed that all the ferrocenyl redox centers are electrochemically independent and undergo a quasi-reversible oxidation at similar potentials. Also, antibacterial activity was studied against Staphylococcus aureus ATCC 29213, Streptococcus mutans RSHM 676, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. The antimicrobial test results indicated that all the compounds have mild levels of antibacterial activity against both gram negative and gram-positive bacterial species.

Novel vic-dioxime ligands and their Ni(II), Cu(II) and Co(II) complexes have been synthesized. Redox behaviors of the ligands and their complexes have been investigated by cyclic voltammetry. The antimicrobial test results indicated that all the compounds have mild antibacterial activity against both gram negative and gram positive bacterial species.Figure optionsDownload as PowerPoint slideHighlights
► We have synthesized novel vic-dioxime ligands and some of its transition metal complexes.
► The Ni(II), Cu(II) and Co(II) complexes have been obtained.
► Redox behaviors of the compounds have been investigated by CV.
► The antibacterial activity was studied.