Synthesis and Characterization of Coordination Behavior of Diclofenac Sodium Drug Toward Hg(II), Pb(II), and Sn(II) Metal Ions: Chelation Effect on Their Thermal Stability and Biological Activity

Diclofenac sodium compound has great biological, medical, industrial, and coordination applications. Most of its metal complexes have antibacterial and antifungal effects. A general survey of previous literature concerning the interaction of transition metals with diclofenac compound was given. From this survey, it is appeared that deep chemical studies were needed to through lighter on the complexing ability and chemical properties, due to presence of active groups such as amino, hydroxyl, carbonyl, and carboxyl groups. Therefore the present work was aimed mainly to study the spectroscopic, stability, and related thermodynamic parameters, structural, thermal, molar conductivity, and biological properties of the diclofenac sodium with selected metal ions such as Hg(II), Pb(II), and Sn(II). The used of theoretical concepts and experimental techniques were discussed. Solid complexes have been prepared and characterized by IR, UV-Vis, elemental analysis CHN, and H-1-NMR. Diclofenac reacts with Hg(II), Pb(II), and Sn(II) by molar ratio (2:1) (diclofenac:metal ion). IR, UV-Vis, spectra indicate that diclofenac behaves as a monobasic bidentate ligand coordinated to the metal ions via the deprotonated carboxylate O and carbonyl groups. The Hg(II), Pb(II), and Sn(II) complexes of diclofenac are found to have high activity against bacteria, especially Bacillus subtilis, and fungi, especially Aspergillus niger, whereas the Pb(II) complex is more active than the Sn(II) and Hg(II) complexes.