الفهرس 
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Abstract
Curcumin, L-tyrosine, L-arginine and their transition metal complexes have been well documented in the literature due to their pharmaceutical applications as good antimicrobial, anticancer and antiviral agents. The current interest in curcumin, L-tyrosine, and L-arginine is due to the presence of various donor atoms (N, O-donors), which exhibit diverse bonding modes leading to different structural motifs. The main aim of the present thesis is focused on the preparation and characterization employing elemental analyses, thermal (TGA and DTGA), spectral (FTIR, NMR, UV-Vis, mass, PXRD and ESR) and magnetic measurements of new complexes of curcumin-tyrosine with Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Hg(II), Pd(II), and U(VI)O22+ metal ions and curcumin-arginine with Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Pd(II), and VO2+ metal ions. Also, theoretical calculations using DFT theory, biological activity, and molecular docking studies were performed. A brief description of the overall work in this thesis can be summarized as follow : The present thesis includes three main chapters: introduction, experimental, results and discussion as well as English, and Arabic summary. ⮚ Chapter one displays a literature survey on some transition metal complexes of L-tyrosine, L-arginine and curcumin with a great attention to the compounds similar to that investigated and their biological activities as well as medical importance. ⮚ The second chapter covers the experimental part and illustrates the experiments used in this work. It includes a list of reagents along with the physical measurements and instrumentation. The working procedures of computational studies were also discussed as well as a description for the preparation of the metal complexes. In addition, this chapter includes the recommended procedures for the antioxidant, antimicrobial, DNA degradation and the antitumor activity of the 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 metal complexes are in good agreement with the stoichiometries concluded from their analytical data of carbon, hydrogen, nitrogen, chloride 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 and the existence of the solvent 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 : ✔ Curcumin-tyrosine ligand acts as binegative tridentate (NOO) in [Zn(curtyr)(H2O)].3H2O, [Mn(curtyr)(H2O)3].4H2O, [Fe(curtyr)(H2O)3]Cl.3H2O, and [UO2(curtyr)(H2O)].H2O complexes. The coordination was through the nitrogen atom of (C=N)azomethine, and the deprotonated oxygen atoms of enolic carbon (C-O) and carboxylate group (COO) for Zn(II), Mn(II), Fe(III), and U(VI)O22+ complexes. ✔ Curcumin-tyrosine ligand acts as mononegative tridentate in [Ni(Hcurtyr)(H2O)3]Cl.2½H2O, [Co(Hcurtyr)(H2O)3]Cl.3H2O, and [Cu(Hcurtyr)(H2O)3]Cl.2H2O complexes via the nitrogen atom of (C=N)azomethine , the deprotonated oxygen of enolic carbon, and the protonated oxygen of carboxylic group for Ni(II), Co(II), and Cu(II) complexes. ✔ Two modes of chelation were observed in case of [Pd2(Hcurtyr)(curtyr)(H2O)2]Cl.3H2O. Complex : Curcumin-tyrosine ligand (curtyr) performs as )NOO( binegative tridentate through (C=N)azomethine and both the deprotonated oxygen atoms of enolic carbon and carboxylate group. Moreover, the ligand (Hcurtyr) behaves as )NOO( mononegative tridentate via (C=N)azomethine and both of the deprotonated oxygen of enolic carbon and the protonated oxygen of carboxylic group. ✔ Different mode of chelation is observed in case of [Hg(Hcur(tyr)2)(H2O)Cl)].2H2O complex: The ligand behaves a (NNOO) mononegative tetradentate via the coordinated nitrogen atoms of (C=N)azomethine and NH groups and the protonated oxygen of carboxylic group. ✔ Curcumin-arginine ligand acts as mononegative tridentate in [Mn(curarg)(H2O)3].4H2O, [Fe(curarg)(H2O)2Cl].2H2O, [VO(curarg)(H2O)].2H2O, [Pd(curarg)(H2O)].3H2O, [Ni(curarg)(H2O)3].5H2O, [Co(curarg)(H2O)3].4H2O, and [Cu(curarg)(H2O)3].H2O. The coordination was through the nitrogen atom of (C=N)azomethine, and the deprotonated oxygen atoms of enolic carbon and carboxylate group. 4. The geometries of complexes are suggested basically on the data evaluated from spectral and magnetic measurements. Octahedral environments are observed for all the complexes except for Pd(II), Zn(II), and VO(II) complexes. 5. Good information about the geometry and the degree of covalency of the metal-ligand bond for [Cu(Hcurtyr)(H2O)3]Cl.2H2O, [Cu(curarg)(H2O)3].H2O, and [VO(curarg)(H2O)].2H2O complexes is elucidated using ESR spectra. The spin Hamiltonian parameters of the complexes has been calculated confirming the octahedral geometry for Cu(II) complexes and the square-pyramidal geometry for VO(II) complex. 6. In order to assess the influence of the structural properties and the type of the metal on thermal behavior of the complexes, the order (n) and the heat of activation (Ea) of the various decomposition stages are determined from the TGA and DTGA 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. 7. The molecular modeling is drawn and demonstrated both bond lengths and angles, chemical reactivity, MEP, and binding energy (kcal/mol) for the investigated compounds. 8. The biological activity of the compounds was investigated for DNA bioassay utilizing gel electrophoresis technique, antitumor via MCF-7 and PC-3 cell lines, antioxidant using DPPH and ABTS, antibacterial and antifungal agents against different types of bacteria and fungi. 9. The final part in this chapter deals with the molecular docking of the isolated compounds against the three-dimensional complex structure of prostate cancer (PDB ID: 3QUM) and breast cancer (PDB ID: 3T6G) targets, which show good binding affinities with these proteins (negative docking score) of the isolated compounds towards these targets.