الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Therefore, the work in this thesis is focused on the preparation and characterization employing elemental analyses, thermal (TG and DTG), spectral (IR, UV-Visible and 1H NMR) and magnetic measurements of new complexes of 2-oxo-N’-((4-oxo-4H-chromen-3-yl)methylene)-2-(phenylamino)acetohydrazide(H2OCAH), N’-(1-(4-hydroxy phenyl) ethylidene)-2-oxo-2-(phenylamino)acetohydrazide(H3OPAH) and N’-(4-methoxybenzylidene)-2-oxo-2-(phenylamino)acetohydrazide (H2OMPH) with Mn(II), Co(II), Ni(II), Cu(II), Cd(II), Zn(II), Hg(II) and U(VI)O2 metal ions. The pH-metric titrations and biological activity were carried out. A brief description of the overall work in this thesis can be summarized as follow: Chapter one displays different publications concerning the complexation of hydrazones with a great attention to the compounds similar to that investigated and their biological activities. The second chapter covers the experimental part and illustrates the experiments used in this work. It includes the physical measurements and instrumentation. The working procedures and pH metric titrations were also discussed as well as a description for the preparation of the ligand and its metal complexes. In addition, this chapter includes the recommended procedures for the antimicrobial activity of some prepared metal complexes. Chapter three deals with the results and discussion which are summarized to give the following information: 1- The proposed chemical formulae of the ligands and their metal complexes are in good agreement with the stoichiometries concluded from their analytical data of carbon, hydrogen and metal contents. 2- Most of complexes have high melting points (>300˚C) and insoluble in most organic solvents. 3- The coordination sites of the ligand, the nature of metal-ligand bonds, the nature of the acetate groups and the existence of the solvated molecules have been elucidated using IR spectra. Different modes of chelation for the investigated ligands are suggested based on careful comparison between the spectra of the ligands and their corresponding complexes. The data obtained are summarized as: 4- The 1H NMR spectra of the diamagnetic Cd(II) and Zn(II) complexes are used to detect the potential coordination sites. 5- Detailed thermal analysis for the prepared complexes was performed in the temperature range 30-700 or 800˚C. The thermograms show the decomposition steps after which a constant weight is observed corresponding to the remaining part of the complex. 6- The geometries are suggested for the prepared complexes based on the data evaluated from spectral and magnetic measurements; [Cu(H2OCAH)Cl2(H2O)]H2O, [Mn(H3OPAH)2Cl2], [Co(H2OCAH)Cl2(H2O)2], [Co2(H2OPAH)2Cl2(H2O)4], [Mn(H2OMPH)Cl2(H2O)2]H2O, [Co(HOMPH)2]H2O and [Ni(H2OMPH)Cl2(H2O)]H2O complexes assigned octahedral structure. [Ni(HOCAH)Cl] and [Ni2(HOPAH)Cl2(H2O)2]H2O complexes have tetrahedral structure while [Ni2(HOPAH)Cl2(H2O)2]H2O, [Cu2(H2OPAH)Cl3(H2O)]H2O, and [Cu(H2OMPH)Cl2]H2O have square planar structure. 7- In order to assess the influenced of the structural properties of the ligands and the type of the metal on thermal behaviour of the complexes, the order (n) and the heat of activation (Ea) of the various decomposition stages are determined from the TG and DTG using the coats-Redfern and Horowitz-Metzger methods. This section includes also the determination of the thermodynamic parameters of activation (ΔH*, ΔS* and ΔG*) which can be calculated by Erying equation. 8- The ionization constant of H2OMPH and H3OPAH and the stability constant of some complexes have been evaluated using the pH-metric data at different temperature. The acid-base character of the ligands is discussed based on its pH-metric titration with NaOH. The stability constants of the formed complexes have been evaluated using Irving-Rossotti model. In addition, thermodynamic parameters have been determined 9- The final part in this chapter deals with the antibacterial activity for H2OCAH and its metal complexes. [Cd(HOCAH)Cl]H2O and [UO2(H2OCAH)(OAc)2]H2O complexes exhibited high inhibitory effects on Bt while [Hg(H2OCAH)Cl2]H2O complex against Pa organisms. The lowest one is H2OCAH while H2OCAH and [Cu(H2OCAH)Cl2(H2O)]H2O showed weak activity against Gram-positive bacteria and gram-negative bacterium.