الفهرس 
Aim and plan of the workOnly 14 pages are availabe for public view
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Abstract
I- Aim of the work
The work aimed to prepare and characterize new Schiff-base amide ligand and its metal complexes to study their biological activity of antitumor agents to explore some effective compounds to be used in treatment of breast cellular carcinoma (MCF-7 cell lines).
II- Introduction
This chapter includes an overview of previous research for complexes of Schiff –base ligands and their applications.
Metal complexes are small molecules that have been widely used as therapeutic agents, functioning as biological agents exhibiting remarkable chemotherapeutic properties. Cisplatin and its analogs are one of the first clinically proven and successful anticancer drugs, and it efficiently binds to DNA resulting in cell apoptosis. Nonetheless, these compounds cause adverse side effects like nausea, neurotoxicity, and nephrotoxicity. Additionally, the excessive use of these drugs results in acquired or intrinsic resistance against some cancer types. Due to the factors mentioned above, the scientific community has invested significant time and effort towards the design and development of novel chemotherapeutic agents that can disrupt or halt the cancerous cellular mechanisms wherein nucleic acids are targeted as they are the precursors aiding the process of cell replication. Nucleic acids are vital biomolecules influencing several cellular functions. According to the Watson and Crick model, DNA is a double helical structure wound in a right-handed manner. DNA is made up
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of a sugar-phosphate backbone and nucleotide bases adenine (A), guanine (G), thymine (T), and cytosine (C), where these bases are connected via hydrogen bonding. The double-helical structure of the DNA shows the presence of minor and major grooves in them. When the two strands are close to each other, they form a minor groove and when they are away, major grooves are formed. These two strands of DNA are composed of nucleotides bases. The two strands of the DNA are complementary, and they run antiparallel to each other. The first strand extends from 5’ OH group of Small molecules or metal complexes binding to these nucleic acids induces changes including structural deformation, resulting in the desired function that can be used to diagnose and treat several diseases.Biomolecule-conjugated metal complexes-based cancer targeting strategies have shown tremendous advantages in cancer therapy .
Cisplatin`s clincal use limited due to the appearance of hazardous side effects like nephrotoxicity , nevrotoxicity and cyto toxicity[].the drawbacks of cancer therapy are mainly the lack of specifity of drugs as well as development of drug resistance.As a result , second- generation anti cancer medicines such as metal-based complexes with a tailored drug delivery mechanism are being developed as potential alternatives.Metal complexes for antibreast cancer such as ;Gold(III) complexes , Pt(II) complexes ,Ruthenium complexes and cisplatin. Transition metal-based compounds are felicitous binding agents that exhibit specific binding interactions towards nucleic acids and several other proteins, making them useful in the field of chemotherapeutics. More over, the spectroscopic characteristics of transition metal-based probe molecules enable their use in various biophysical investigations related to the development of various anticancer agents. The varying coordination numbers, redox potentials, and geometry
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which cannot be actualized by conventional organic compounds make these molecules significant among all anticancer agents developed so far The efficacy of these probes (metal complexes) is governed by the ability to read the information in the DNA duplex resulting in the effective binding of these probes with DNA. After binding, the probes are anchored into the DNA duplex through a number of interactions such as stacking, hydrogen bonding, van der Waals forces, and so on Herein were synthesized and characterized new organometallic complexes of (1Z,2Z)-N1,N’1,N2,N’2-tetrakis(2-hydroxyphenyl)oxalimidamide which candidate as potent antitumor agents for breast cancer MCF-7 cell line.
III- Experimental
This chapter contains the chemical and instruments used in Practical part of thesis as follow:
1) Preparation of the Schiff –base ligand and its metal complexes.
2) characterization of the ligand and its complexes using:
Physical techniques such as molar conductance, magnetic susceptibility and melting point.
Elemental analyses (C, H, N, Cl and M).
Spectral techniques as IR, UV- Vis., 1H-NMR, massspectra and ESR measurements.
Thermal techniques as DTA and TGA
3) Measurement of biological activity.
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IV- Results and discussion
This chapter includes characterization of the ligand and its metal complexes. Organometallic complexes of Cu(II), Mn(II), Pb(II), Zn(II), Fe(III), and Ni(II) ions with ((1Z,2Z)-N1,N’1,N2,N’2-tetrakis (2-hydroxyphenyl) oxalimidamide ligand had much potential as antitumor agents. These complexes were prepared and characterized by elemental analyses, IR, UV-Vis spectra, Magnetic moments, Conductivity, 1H-NMR and Mass spectra, Thermal analyses (DTA and TGA) and ESR measurements. The elemental analyses, spectral data reveal that, the formed complexes are colored, stable in the air and soluble in solvents such as DMF, DMSO and ethanol.
The antitumor activity was tested against human breast cancer cell lines (MCF-7) and the tested complexes showed high activity against breast cancer.