الفهرس 
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Abstract
The thesis contains three main chapters concerned with transition metal complexes of Schiff bases derived from some aliphatic amino acids (serine, arginine and glycine) and acetylacetone.
The first chapter includes an introduction and a literature survey on the metal complexes of amino acids and their Schiff bases derivatives.
The importance of this type of metal complexes is attributed to its prominent role in various fields, in addition to its multiple biological activities. Recent researches showed the effectiveness and activity of Schiff bases derived from amino acids against many tumors.
Schiff base complexes of amino acids are prepared by the condensation of NH2 group with carbonyl oxygen to form the azomethine linkage. These compounds are unstable in solution. As is well-known, it is hard to isolate Schiff base derived from amino acid due to its presence in the Zwitterion form. The literature survey showed that most of the published works on Schiff bases concern with the compounds derived from the condensation of amino acids with salicyaldehyde and its derivatives. Few works deal with Schiff bases derived from amino acids and aromatic ketones. Most of the work done did not touch significantly to Schiff bases derived from amino acids with aliphatic ketones. Finally, this chapter is ended with the aim of work.
The second chapter of the thesis is concerned with the experimental work. The practical preparation of the Schiff base solid complexes derived from amino acids (serine, arginine and glycine) with acetylacetone in the presence of metal acetates “copper, cobalt, nickel and zinc” acetates are described. Also this chapter deals with working procedures, apparatus and methods of experimental measurements and includes some of the physical properties of these complexes.
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The third chapter of the thesis includes on the results and discussion. The results showed the isolation of solid complexes from the condensation of aliphatic amino acids (serine, arginine and glycine) with acetylacetone in the presence of metal acetates.
By studying the infrared spectra of the isolated solid complexes and their constituents, it was observed the absence of the bands assigned to (NH2), of the amino acid and (C=O) of acetylacetone from the spectra of the metal complexes, together with the appearance of new bands assigned to the azomethine group (C=N*) and olefin group (CH=C). The presence of these groups suggests that the condensation process has been occurred and the Schiff base exists in enol form. The results indicated that the condensated ligands derived from serine and arginine behave as a bi-negative tridentate ligands chelating the meal ion via the azomethine nitrogen (C=N*), the carboxylate oxygen and acetylacetonate oxygen in the enol form with displacement of a hydrogen atom from the latter groups. The condensated ligand derived from glycine behaves as a bi-negative tetradentate coordinating to two meal ions in the same time. It coordinates to the first ion via the azomethine nitrogen (C=N*) and acetylacetonate oxygen in the enol form with displacement of a hydrogen atom from the latter group. While, it binds to the second metal ions through the carboxylate oxygens in bidentate manner.
The geometries of the isolated solid complexes were determined with the help of the electronic spectra and magnetic measurements.
Electron spin resonance (ESR) studies provided important informations that help in determining the stereochemistry around the Cu(II) ion. The results indicated that the isolated Cu(II) complexes exist in square planar geometry.
The thermal analysis (TGA and DTA) measurements have been carried out to calculate the amounts of the solvents inside and/or outside the coordination sphere. Also, it was used to illustrate the steps of the thermal decomposition to get the metal oxides. The thermodynamic parameters (E*, ΔH*, ΔG* and ΔS*) were calculated, the positive values of ΔH* shows endothermic decomposition, the positive values of ΔG* indicate the non-spontaneous character
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of the decomposition steps and the negative ΔS* values indicate that the activated complexes have more ordered structure than the reactants.
Molecular mechanics technique and the semi-empirical AM1 and PM3 methods are used to investigate the geometries of the suggested structures, where the absorption spectrums in ultraviolet and visible region for complexes of copper, cobalt, nickel were calculated and compared with the experimental results, where it turns out the existence of consensus between the calculated and the practical values. Theoretical calculations helped in determining the absorption bands which did not appear in the measured spectra. As well as theoretical calculations were used in determining the bond lengths and angles for the complexes under investigations.
Some optical properties as the optical band gaps (Eg) of the studied complexes were measured to clarify the conductivity nature of the isolated complexes. The results indicated direct band gap (Eg) equal 3.3 - 3.5 eV for Schiff base complexes derived from glycine and 3.3– 4.4 eV for Schiff base complexes derived from serine and arginine. These values suggest that these complexes are semi-conductors. As well as the optical band gaps were calculated theoretically using AM1, PM3 methods and the results showed compatibility between the theoretical and practical values.
Finally, the biological activities of Cu(II) complex was studied. Molecular docking is used to predict the binding between serine Schiff-base with the receptor of prostate cancer mutant H874Y. The results indicated that the present Schiff base ligand is efficient inhibitor of prostate cancer mutant H874Y. The interactions between the Cu(II) complex and calf thymus DNA (CT-DNA) is studied by UV spectra for the Schiff base derived from serine and glycine. The results confirmed that these Cu(II) complexes bind to CT-DNA in an intercalative mode, which reflects the possibility of use of these complexes in the treatment of cancer.