Mixed-Ligand Nickel(II) Complexes Containing Sulfathiazole andCephalosporin Antibiotics: Synthesis, Characterization, andAntibacterial Activity

摘要

Nickel(II) reacts with cephalosporins plus sulfathiazole (Hstz) to form the following mixed-ligand complexes of general formulae [Ni(L)(stz)(H2O)x]n(L1,4,x=1;L2,3,x=0; L = monoanion of cefazolinHL1, cephalothinHL2, cefotaximeHL3, ceftriaxoneHL4) and [Ni(L5)(stz)]Cl (cefepimeL5), which were characterized by physicochemical and spectroscopic methods. Their spectra indicated that cephalosporins are acting as multidentate chelating agents, via the lactam carbonyl and carboxylate and N-azomoieties. The complexes are insoluble in water and common organic solvents but soluble in DMSO, where the [Ni(L5)(stz)]Cl complex is 1 : 1 electrolyte. They probably have polymeric structures. They have been screened for antibacterial activity, and the results are compared with the activity of commercial cephalosporins.