Cu(II), Zn(II), Cd(II) and Hg(II) Complexes of Omeprazole (PPZH): Synthesis and Characterization

Omeprazole is a widely used proton pump inhibitor. This is used for the treatment of gasteo-oesophageal reflux diseases as well as acid induced inflammation disorders of the stomach and duodenum. In the scheme of gradual release and extended acting drugs, metal complexes of the parent drugs are achieving growing importance. Complexes of metallic salts with PPI are known to be more effective and lower in toxicity in numerous circumstances as compared to the original drug itself. In this report, compounds of omeprazole with several metal salts such as copper, zinc, cadmium and mercury have been synthesized. The powders were analyzed applying different characterization techniques such as elemental analysis, infrared and ultraviolet-visible spectroscopy, thermal analysis including both TGA and DSC (differential scanning calorimetric), and finally magnetic susceptibility measurement. Omeprazole (OPZ) behaves as a bidentate ligand forming coordination compounds with metal ions having +2 charge. Anionic imidazolyl nitrogen (N-) and oxygen atom of sulfinyl >S=O group participate in coordination bond formation. Prepared compounds show tetrahedral structure.