Synthesis, Spectroscopic, Thermal Studies and Biological Activity of a New Sulfamethoxazole Schiff Base and Its Copper Complexes

A new Sulfamethoxazole Schiff base (E)-4-(4-methoxybenzylideneamino)-N(5-methylis-oxazol-3-yl) benzenesulfonamide (C18H17N3O4S), and its copper complex were synthesized and the structures elucidated on the basis of Physiochemical methods. The studies indicate an octahedral structure for the complexes with the (C22H27N3O10SCu) formula. The IR spectra suggest that the ligand act as tridentate (from oxygen and two nitrogen atoms) donor. Also the biological activity of the Schiff base and its Cu complex were studied. INTRODUCTION: Schiff base compounds which contain the azomethine (imine) group (–RC=N–) are usually prepared by the condensation of a primary amine with an active carbonyl compound . It has been often used as chelating agents (ligands) in the field of coordination chemistry and Schiff base metal complexes were of great interest for many years. It is well known that O and N atoms play a key role at the active sites of numerous metallo biomolecules in the coordination with metals . Later, a great number of sulfanilamide derivatives were synthesized, characterized and tested as antibacterial agents, with many derivatives currently used for the treatment of bacterial infections. Such sulfonamide derivatives widely used in clinical medicine as pharmacological agents with a wide variety of biological actions, were designed from the simple sulfanilamide lead molecule , also Schiff base known as anticancer and antiviral agents , and its metal complexes have been widely studied because they have industrial, anti-fungal, anti-bacterial, anticancer herbicidal applications , anti-tubercular activities 6 and chelating abilities which give it attracted remarkable attention . Sulfa drugs had attracted special attention from their therapeutic importance as they were used against a wide spectrum of bacterial ailments .