Physico-Chemical Studies On Some Metal Complexes Containing Ns,No Or NN Donor System

SUMMARY AND CONCLUSIONThe chemistry of hydrazine and hydrazide derivatives have an increased interest due to their biological activity and industrial application. Many metal complexed derivatives exhibited significant antiviral activity. from the complexing point of view, orgaThe used theoretical concepts and experimental techniques were discussed in details.The results obtained can be summarized as following:1- The protonation constants of the free ligands as well as the stability constants of the formed metal complexes have been determined potentiometrically at different temperatures. The Log KH of the studied ligands at 291 K are found to follow the order :hydrazinecarbodithioic acid > thiocarbonohydrazide > hydrazinecarbo-thioamide > hydrazinecarboxamide > hydrazinecarboximidamide. This sequence was attributed to the increase of basicity of the studied compoundsThe order of the overall stability constants are : Mn < Fe < Co < Ni < Cu > Zn > Cd > Hg, which is in a good agreement with the order found by Irving and Williams.Thermodynamic parameters, the standard free energy change, ΔGo, the standard enthalpy change, ΔHo, and the standard entropy change, ΔSo were determined. The results show that the ΔGo values are negative for all metal complexes indicating that the complex In order to investigate the nature of metal-ligand bond in the studied complexes, the thermodynamic parameters were separated into two components, electrostatic (ionic) and non- electrostatic (covalent) terms. The results show that the negative value of Δ2- Solid complexes have been prepared and characterized by elemental analysis, IR and 1HNMR spectral studies. The obtained spectra show that all the ligands are bounded to the metal ions through the hydrazinic nitrogen atom and oxygen or sulfur atoms.3- Thermogravimetric analysis (TGA) of the complexes were carried out to identify their thermal stabilities structure. Also the activation energy and the other kinetic parameters were calculated from Coats-Redfern equation. The data obtained show that the4- Antimicrobial activities of some complexes compounds against some bacterial and fungal SPP were carried out and it was found that :• The free ligands have no antimicrobial activity against both groups of micro-organisms.• Hg-thiocarbonohydrazide complex is the most potent complex and the clear inhabitation zones reached maximally against B. subtilus and B. aureus.• Ni-complex has no effect against the different species either belong to bacteria or fungi.