الفهرس 
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Abstract
In recent years, great interest has been focused on Fe(II) Schiff bases br amino acids complexes as cytotoxic and antitumor drugs. Thus a series of new br iron(II) complexes based on Schiff bases amino acids ligands have been br designed and synthesized -#102;-#114;-#111;-#109; condensation of 2-hydroxy-1-naphthaldehyde br and 5-bromosalicylaldehyde (bs) with α-amino acids ((L-alanine (ala), Lphenylalanine br (phala), L-aspartic acid (aspa), L-histidine (his) and L-arginine br (arg)). Structure elucidation of the investigated iron(II) complexes were br determined using elemental analyses, infrared, ultraviolet-visible, br thermogravemetric analysis, as well as conductivity and magnetic br susceptibility measurements. Moreover, the stoichiometry and the stability br constants of the prepared complexes have been determined br spectrophotometrically. The results suggest that 2-hydroxy-1-naphthaldehyde br and 5-bromosalicylaldehyde amino acid Schiff bases behave as dibasic br tridentate ONO ligands and coordinate to Fe(II) in octahedral geometry br according to the general formula [Fe(HL)2].nH2O. But in case of 2-hydroxy-1- br naphthaldehyde with L-histidine, the ligand acts as tetradentate br ([FeL(H2O)2].2H2O), -#119;-#104;-#101;-#114;-#101; HL = mono anion and L = dianion of the ligand. br The conductivity values between 28–64 Ω−1 mol−1 cm2 in ethanol imply the br presence of nonelectrolyte species. The pH profile revealed that, the wide br range of pH stability of the investigated complexes is at pH = 4-10 in most of br them. The complexes structures were validated using quantum mechanics br calculations based on accurate DFT methods. The solubilities of investigated complexes in water-ethanol, water-propanol, water- acetone and water-DMSO br mixtures were established and their transfer chemical potentials were calculated. It was observed that the hydrophobicity of the investigated br complexes leads to stabilization of them with increasing solvent percent. br The -#111;-#114;-#100;-#101;-#114; of hydrophobicity according to the following sequence: br nhi -lt; bsasi -lt; bsali -lt; nasi -lt; nali -lt; bsari -lt; nari -lt; bshi -lt; bsphali -lt; nphali br In addition, the prepared complexes were tested for their toxicity on chick br embryos and found to be safe until a concentration of 100 µg / egg with full br embryos formation. Moreover, the prepared compounds are screened for their br in-vitro antibacterial and antifungal activity. The results of these studies indicate br that the metal complexes exhibit a stronger antibacterial and antifungul br efficiency than their corresponding ligands. Furthermore, the interaction of the br investigated complexes with (CT-DNA) was investigated by using br spectromphotometry, viscosity, agarose gel electrophoresis measurements and br kinetic studies. The experimental results indicated that the investigated br complexes strongly bind with CT-DNA via intercalative mode and showed a br different DNA binding activity according to the sequence: nhi -gt; bsari -gt; bshi -gt; br bsali -gt; bsasi -gt; nari -gt; bsphali -gt; nali -gt; nasi -gt; nphali. br Furthermore, kinetic results, rate laws and reaction mechanism were established for the base hydrolysis of the investigated complexes in aqueous br solution, water-ethanol, water-propanol, water-acetone and water-DMSO br mixtures and in the presence of salts: LiBr, KBr, NaCl, TMTB, TETB and br TBAB. The base hydrolysis reaction of all the investigated complexes follow br the general rate law: ] ])[ [ ( ] [ 2 1 complex OH k k complex k Rate obs br - + = = br The k1 term is assigned to rate determining dissociation of the investigated br complexes and the k2 term to rate determining attack by OH- at the complexes, br -#119;-#104;-#101;-#114;-#101; kobs = k1+k2 [OH-]. br The suggested mechanism of the base hydrolysis reaction involves the br parallel attack of OH- ion on Fe2+ central atom attached to a singly bonded OH- ligand and dissociation of the first ligand as rate determining step. The kinetic br data leaded to Gibbs free energies of activation (the change in activation barrier δm∆G#). br The activation parameters of the base hydrolysis reaction are evaluated br and discussed by carrying out the base hydrolysis of the studied complexes in br aqueous solution at different temperatures. The high negative values of entropy br of activation (∆S#) support the proposed mechanism. br Solvent effect on reactivity trends of the investigated complexes have been br analyzed into initial and transition state components by using the transfer chemical br potentials of the reactants and the kinetic data of the studied complexes. br The decrease in the observed rate constant values (kobs) of the base br hydrolysis of the investigated complexes with increasing of solvent % is br dominated by the initial state (IS). Generally, the presence of the salt markedly br enhances the rate compared to its absence. This behavior agrees with the br anionic nature of the transient species. With increasing added NaCl, LiBr and br KBr, the rate of the reaction increases. But in case of TMAB, TEAB and br TBAB salts, the rate increases and then decreases on increasing their br concentration.