الفهرس 
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Abstract
The entitled thesis “Synthesisand characterization of Coumarin Metal Complexes “comprises three chapters.
Chapter Iis concerned with the literature survey on the published papers and reviews concerning the structural chemistry, formation of complexes and biological activity of coumarins and their various metal complexes. This chapter ended with the aim of the work.
Chapter II is devoted to discuss the experimental part. The preparation of (E)-2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hydrazinecarboxamide HL1, E)-2-(1-(2-oxo-2H-chromen-3-yl)ethylidene)hydrazinecarbothioamide HL2 ligands and their copper(II), zinc(II), silver(I) and gold(III) complexes. The analytical data of the ligands and their complexes are given, the instruments used are also mentioned. The bio-activity measurements concerning the cytotoxicity and anticancer assay in addition to in-vitro antimicrobial screening against gram positive, gram negative and Candida albicans fungus are also given in this chapter.
Chapter III is concerned with the results and discussions and divided into sixth parts.
The first part deals withFT-IR spectra, of the free ligands and their complexes. The data showed the position of the fundamental groups, υ(C=O) lactones, υ(C=O) semicarbazide, ν(C=S), υ(C=N) , υasym(C-O-C), υ(C=C) in addition toυasym (NH2), υsym(NH2)The shift of υ(C=O) semicarbazide, ν(C=S) and υ(C=N) to lower wavenumbers in the spectra of complexes support the formation of complexes and that coordination took place via azomethine nitrogen and carbonyl oxygen or thionsulphur. The lactone υ(C=O) stretching frequency remained unchanged in all metal complexes, thus excluding coordination of both ligands through the lactone oxygen,
The second part deals withESR spectra of the prepared copper (II) complexes. The [Cu(HL1)Cl2].H2O and [Cu(HL2)2Cl2].2H2O complexes have axial nature with g║>g_⊥>ge. The average g-value for the two complexes suggests dx²-y² ground state.
The third part related to 1H and 13C-NMR spectra forcoumarin ligands and their zinc, silver and gold complexes. The protons signal of investigated complexes almost located in the position of their free ligands with decreasing in the intensity. However appreciable changes occurred in the 13C NMR spectra for metal complexes compared to their parent ligands. The shift in the positions of (C=N), (C=O) and (C=S) signals, in the spectra of metal complexes support their coordination to metal ions.
The fourth part describes theelectronic spectra of the free ligands and their metal complexes.The synthesized complexes have different geometrical structures. [Cu(HL1)Cl2].H2O and [Zn(HL1)Cl2].2H2O complexes have square planer geometry. While [Ag(HL1)(NO3)].H2Ocomplex revealed trigonal planer geometry and [Cu(HL2)2Cl2].2H2O, [Zn(HL2)2Cl2].H2O, and [Au(HL2)2(H2O)2].Cl3 complexes are of octahedral geometry. While [Ag(HL2)2(NO3)].2H2O complex showed square pyramidal geometry.
The fifth part deals with the thermal analysis studiesof coumarin ligands their metal complexes using the thermogravimetric analysis (TGA), Differential thermogravimetricanalysis (DTG) and Differential thermal analysis (DTA). The thermodynamic parameters of decomposition processes namely, activation energy Ea*, enthalpy (ΔH*) and entropy (ΔS*) were calculated. The ligand HL1 is more stable than ligand HL2 within temperature range 0–1000ᵒC. Cu(II) and Zn(II) complexes decomposed leaving metal oxide while Au(III) decomposed leaving metal residue as Au atom, however Silver complexes decomposed leaving (C4H5N2OAg) and (C4H8N2O2Ag) as residue. This clearly confirms that the silver complexes [Ag(HL1)(NO3)].H2O and [Ag(HL2)2(NO3)].2H2O are more stable than copper ,zinc and gold complexes.
In the sixth part, the ligands and their complexes are screened against multi-resistant Gram positive bacteria (Staphylococcus spp and Streptococcus spp.), Gram negative bacteria (Pseudomonas spp, Salmonella spp., Escherichia coli, Proteus spp. andKlebsiella spp.) and the fungus, Candida albicans and subjected to cytotoxic activities against human liver cancer cells HepG2. Both ligands exhibited high potency as antibacterial agents, while metal complexes increased the anticancer activity to over 40% in comparison to both ligands.
Finally, the data are collected in (19) Tables, (26) Schemes and (67) Figures. The thesis ended with a list of references (145) used in this work.