Direct electrosynthesis of Cu, Cd, Zn complexes of piroxicam (4-hydroxy-2-methyl- N-(2-pyridyl)-2H-1,2-benzothiazine-3-carboxamide-1,1,-dioxide) and isoxicam (4-hydroxy-2-methyl- N-(5-methyl-3-isoxazolyl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide) in nonaqueous media by in-situ generation of supporting electrolyte

Abstract

The direct electrosynthesis of Cu, Cd and Zn complexes of the anti-inflammatory drugs piroxicam (4-hydroxy-2-methyl- N-(2-pyridyl)-2H-1,2-benzothiazine-3-carboxamide-1,1,-dioxide=H-pir) and isoxicam (4-hydroxy-2-methyl- N-(5-methyl-3-isoxazolyl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide=H-isox) was accomplished by electrochemical dissolution of sacrificial metallic anodes in an acetonitrile solution of the ligand. The chemical and electrochemical in-situ generation of supporting electrolyte was used as a means to obtain pure coordination compounds without the use of supporting electrolytes such as tetraalkylammonium or lithium salts in nonaqueous media. Characterization of the complexes obtained by direct synthesis and comparison with those obtained by traditional synthesis shows that a new copper–piroxicam complex was synthesized.