ABSTRACT
An asymmetric, potentially bidentate dioxime ligand (H2L) was formed by condensation of 4-biphenylchloroglyoxime and napthyl-1-amine. Two equivalents of H2L were reacted with CoCl2 · 6H2O under appropriate conditions with deprotonation of the dioxime ligand. A series of new organocobaloxime derivatives of the type [CoR(HL)2Py], [CoRL2PyB2F4], and [CoRL2Py(Cu(phen))2] (H2L = 4-(napthyl-1-amino)biphenylglyoxime; phen = 1,10-phenathroline; R = izopropyl and benzyl; Py = pyridine) were synthesized. The products were characterized by elemental analysis, molar conductance, FT-IR, ¹H NMR, and magnetic susceptibility measurements. Catecholase-like activity properties of all complexes were also studied. All complexes are catalysts for the oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butyl-1,2-benzoquinone in methanol. Antimicrobial activity studies of H2L and the six complexes were carried out on standard strains (human pathogenic) of bacteria (Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Bacillus cereus, Enterococcus faecalis, Streptococcus pneumoniae, Listeria monocytogenes, Bacillus subtilis, Escherichia coli, Pseudominas aeruginosa, Salmonella typhi) and the yeast Candida albicans. The compounds showed a significant inhibition of the growth of the Gram-positive bacteria tested. Among the tested microorganisms, S. aureus was the most sensitive strain, especially to H2L and its complexes.
Subject(s)
Anti-Infective Agents/pharmacology , Catechol Oxidase/metabolism , Organometallic Compounds/pharmacology , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/chemistry , Bacteria/drug effects , Candida albicans/drug effects , Gram-Negative Bacteria/drug effects , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry , Spectroscopy, Fourier Transform InfraredABSTRACT
Dioxime ligand (H2L) was synthesized by condensation reaction between 4-biphenylchloroglyoxime and 4-chloroaniline. The metal complexes of the types, [Co(HL)2(i-Pr)Py], [CoL2(i-Pr)PyB2F4] and [CoL2(i-Pr)Py(Cu(phen))2](ClO4)2 [H2L = 4-(4-chlorophenylamino)biphenylglyoxime; phen = 1,10-phenanthroline; i-Pr = isopropyl; Py = pyridine] were synthesized and characterized by elemental analysis, FT-IR, 1H NMR and magnetic susceptibility, conductivity measurements. The results of elemental analyses, IR and NMR confirmed the stoichiometry of the complexes and the formation of ligand frameworks around the metal ions. The magnetic moment measurements of the complexes indicated that the complexes are diamagnetic (low-spin d6 octahedral) except trinuclear complex. Furthermore the interaction between the dioxime ligand and its complexes with DNA has also been investigated by agarose gel electrophoresis. The trinuclear Cu2Co complex with H2O2 as a cooxidant exhibited the strongest DNA cleaving activity.
