A Dinuclear Ruthenium(II) Schiff Base Complex with Dissimilar Coordination: Synthesis, Characterization, and Biological Activity
A dinuclear Schiff base RuII complex derived from 5-chlorosalicylaldehyde and 2-aminopyridine was synthesized. The structure of the compound was analyzed by mass spectrometry as well as IR, UV/Vis, and 1H NMR spectroscopy, along with chemical analysis,as well as magnetic, cyclovoltammetric and conductivity measurements. Two RuII atoms are octahedrally coordinated by azomethine and pyridine nitrogen atoms from two tridentate monobasic Schiff bases and bridging phenol oxygen atoms. The formula of the complex is [Ru2L2Cl2(Et2NH)(H2O)] [L = N-(2-pyridyl)-5-chlorosalicylideneimine and Et2NH = isodiethylamine]. The RuII atoms in the dinuclear neutral complex species have different coordination environments, RuN3O2Cl and RuN2O3Cl. Interaction with CT DNA showed moderate hydrophobic binding. The compound demonstrates strong activity against methicillin-resistant Staphylococcus aureus, methicillin-sensitive Staphylococcus aureus, and especially Enterococcus faecalis. Microbiological tests showed significant inhibition of growth and ability to kill pathogens, similar or even improved compared to reference antibiotics vancomycin.