الفهرس 
General Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
Design of macrocyclic and thiosemicarbazone ligands with
various functionalities is a key factor in the advancement of the
coordination chemistry resulting in (i) their ability to modify
binding constants for use in selective metal extraction and as the
therapeutic agents (ii) their a wide applications in pharmaceutical,
analytical and industrial aspects e.g as antibacterial, antifungal,
antimalarial, antineoplastic, anticarcinogenic, anti-HIV,
anticancer, antitumour and antiviral activities and have biological
activities. Their biological activities are considered to be related to
their ability to form chelates with metals. For these applications,
we are extending this field in synthesis novel metal complexes.
Our study comprises five chapters:
Chapter (I) gives a general introduction and literature survey for
some important selected studies on related organic ligands and
their metal complexes.
Chapter (II) explains the practical method of preparation of
ligands and different physicochemical method of analysis such as
(elemental analysis, molar conductivity, 1H-NMR, mass, UV-Vis
and FT-IR spectroscopy) for elucidation the structure of the metal
complexes.
The macrocyclic ligand was prepared via the interaction of
etheylenediamine and ethylacetoacetate, while the thiosemicarbazone ligands were prepared by the condensation of
thiosemicarbizide as starting material, with salicylaldehyde and 3-
formyl chromone in the molar ratio 1:1 to afford the
corresponding thiosemicarbazone ligands; H2L2 and HL3,
respectively.
Chapter (III) aims to production of macrocyclic ligand H2L1 and
its complexes with Cd(II), Co(II), Cu(II) and Ni(II) ions in a
molar ratio (1:1, ligand: metal ion). These complexes were
characterized on the basis of elemental analysis, molar
conductivity, 1H-NMR, mass, UV-Vis and FT-IR spectroscopy.
All results confirmed that the prepared compounds have 1:1
metal-to-ligand stoichiometry, an octahedral configuration and the
ligand behaves as a neutral tetradendate towards the metal ions.
Thermal studies suggest a mechanism for degradation of the metal
complexes as a function of temperature supporting the chelation
modes, moreover, show the possibility of obtaining new
complexes pyrolytically in the solid state which cannot be
synthesized from the solution. The analytical results of the
pyrolytically prepared complexes showed that the ligand behaves
either as a neutral or dianoinic tetradentate ligand towards the
metal ions. The binding of H2L1 and its copper(II) complex (3) to
HS-DNA were studied. The experimental results suggested that
the H2L1 and its copper(II) complex (3) bind to HS-DNA through
an intercalative mode. Anti-tumor activiy of the H2L1 and its copper(II) complex were studied against Ehrlich Acites
Carcinoma (E.A.C) and colon carcinoma cell lines growth. The
H2L1 and its copper(II) complex possess remarkable activities.
Chapter (IV) focuses on synthesis, characterization and thermal
studies of binary and/or mixed complexes based on 2-
(Hydroxybenzylidene) thiosemicarbazone (H2L2) with Cd(II),
Cu(II), Ni(II) and Co(III) ions.
The results obtained in this chapter were summarized as follows:
- The changes in the selected vibrational absorption in FT-IR and
1H-NMR spectra of the Schiff base ligand upon coordination
indicate that the ligand behaves as monoanoinic tridentate ligand
manner with ONS donor sites via oxygen atom of the phenolic
group, nitrogen atom of the azomethine group and sulfur atom of
the thiocarbonyl group.
- All binary complexes of Cu(II), Ni(II) and Co(III) ions have 1:1
metal-to-ligand stoichiometry, but in case of Cd(II) complex has
1:2 metal-to-ligand stoichiometry.
- The analytical data of metal chelates indicate that the metal ions
in case of all mixed ligand complexes are coordinated to one
mixed ligand molecule (Gly, 2-Ampy or Phen) in addition to one
H2L2 molecule.
- In the mixed ligand complexes, glycine (Gly), acts as
monoanonic bidentate ligand via the amino group and carboxylate
group, while 2-aminopyridine (2-Ampy) acts as a neutral monodentate via the amino group but 1,10-phenanthroline has two
pyridine rings nitrogen and acts as bidentate ligand.
- All complexes have octahedral configuration, except binary
Cu(II) complex (10) and Ni(II) complex (14), which have
tetrahedral and square planer geometries, respectively.
- Thermal studies suggest a mechanism for degradation of the
metal complexes as a function of temperature supporting the
chelation modes, moreover, show the possibility of obtaining new
complexes pyrolytically in the solid state which cannot be
synthesized from the solution.
- The binary Cu(II) complex has a high binding affinity to HSDNA.
Chapter (V) deals with preparation of new series of metal
complexes of Cd(II), Cu(II), Ni(II), Co(III) and Fe(III) with Schiff
base ligand, HL3, 3- formyl chromone thiosemicarbazone. In
addition, the mixed ligand complexes were prepared by using
glycine (Gly), 2-aminopyridine (2-Ampy), potassium thiocyanate
(KSCN), 8-hydroxyquinoline (8-HOqu) and 1,10-phenanthroline
(Phen) as secondary ligands. Also, new solid complexes were
prepared pyrolytically in the solid state which cannot be
synthesized from the solution by heating their mother complexes
at the temperature at which the endo or exothermic peak was
observed from DSC analysis.
All synthesized compounds were identified and confirmed
by elemental analyses, molar conductivity, UV-Vis, FT-IR and H-NMR spectroscopy and magnetic moment measurements as
well as TG-DSC technique. The changes in the selected
vibrational absorption in FT-IR and 1H-NMR spectra of the Schiff
base ligand upon coordination indicate that the ligand behaves
either as neutral or monoanonic ligand manner with ONS donor
sites via the oxygen atom of the carbonyl group, the nitrogen atom
of the azomethine group and sulfur atom of thiocarbonyl group.
According to analytical data, all binary complexes of
Cu(II), Ni(II), Co(III) and Fe(III) ions have 1:1 metal-to-ligand
stoichiometry, but in case of Cd complex have 1:2 metal-to-ligand
stoichiometry. Moreover, the analytical data of metal chelates
indicate that the metal ions in case of all mixed ligand complexes
are coordinated to one mixed ligand molecule (Gly or 2-Ampy or
SCN or 8-HOqu or Phen) in addition to one HL3 molecule.
In the mixed ligand complexes, glycine (Gly), acts as
monoanonic bidentate ligand via the amino group and carboxylate
group, while 2-aminopyridine (2-Ampy) acts as a neutral
monodentate via the amino group but thiocyanate (SCN), acts as
monoanonic monodentate ligand. In case of 8-hydroxyquinoline
(8-HO-qu), behaves as monoanonic bidentate ligand via the amino
group and hydroxy group but 1,10-phenanthroline (Phen) has two
pyridine rings nitrogen and acts as bidentate ligand.
Finally, the binary Cu(II) complex showed binding affinity
to HS-DNA through intercalative.