Metal complexes of a Schiff base ligand derived from cefotaxime and salicylaldehyde were prepared. The salicilydene-cefotaxime ligand (H2L) and mononuclear [M(L)] (M(II)？=？Co, Ni and Cu), dinuclear [Ag2(L)(OAc)2], and tetranuclear metal complexes [M4(L)(OH)6] (M(II)？=？Ni, Cu) were characterized on the basis of analytical, thermal, magnetic, and spectral studies (IR, UV-visible, 1H NMR, 13C NMR, and EPR). The electronic spectra of the complexes and their magnetic moments suggesttetrahedral geometry for the isolated complexes. The complexes are nonelectrolytes and insoluble in water and common organic solvents but soluble in DMSO. 1. Introduction Interaction between transition metals and proteins is ubiquitous in biochemistry [1]. The fundamental intrinsic nature of these interactions can be studied in metal complexes with amino acid Schiff bases [2], which has led to the suggestion that Schiff bases act as a tridentate ligand containing an azomethine nitrogen atom and the terminal two oxygen atoms of the carboxylate group as well as the hydroxyl group [3]. The field of Schiff base complexes has been fast developing on account of the wide variety of possible structures for the ligands depending upon the aldehydes and amines considered, and various Schiff bases were reported to possess genotoxicity [4–6], antibacterial [7, 8], and antifungal activities [9]. The increasing interest in transition metal complexes containing a Schiff base ligand is derived from their well-established role in biological systems as well as their catalytic and pharmaceutical applications [10, 11]. Although the chemistry and spectroscopy of metal complexes of Schiff bases derived from aldehydes and/or ketones and amino acids have been widely studied, rather less is known about their antibiotic analogues. A literature survey revealed that little work involving metal-based antibiotics has been reported so far. Cefotaxime is a third generation cephalosporin antibiotic; like other -lactam antibiotics, it has a broad-spectrum antimicrobial activity [12]. Since the coordination environments of metals in metal-based antibiotics is not well-known and continuing with our studies in order to shed more light on the nature of mono- and polynuclear Schiff base complexes containing antibiotics [13–18], we report here the isolation and characterization of metal(II) complexes containing a Schiff base ligand derived from cefotaxime antibiotic and salicylaldehyde. 2. Experimental 2.1. Materials and Methods All necessary precautions were taken to exclude oxygen and moisture during the synthesis and
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