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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Deriváty TACN s aminofosfinátovými pendantními skupinami / TACN derivatives bearing aminophosphinate pendant arms

Beranová, Tereza January 2016 (has links)
The aim of this work was studying of the coordination properties of TACN macrocyclic derivatives with aminophosphinate pendant arms. Two ligands were prepared, one with two pendant arms NODPam and one with three pendant arms NOTPam. Because of degradation of ligand NODPam during its synthesis, only the ligand NOTPam was studied further. Acid-base properties of ligand and termodynamic stability of aluminium and gallium complexes were studied. Formation and disociation studies were performed with the complexes. Coordination of fluoride ions to aluminium complex was studied using ion selective fluoride electrode. Finally coordination of complex AlFx with ligand NOTPam was studied using 19F and 27Al NMR spectroscopy. Selected experiments were made also with ligand NOTA. Key words: macrocyclic complexes, positron emission tomography, phosphinic acids
12

Detekce kovalentních komplexů DNA s proteiny jako metoda stanovení poškození DNA topoizomerázovými jedy. / DNA-protein covalent complexes detection as the means for the assessment of the DNA damage induced by topoisomerase poisons.

Karešová, Aneta January 2016 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Aneta Karešová Supervisor: PharmDr. Anna Jirkovská, PhD. Title of diploma thesis: DNA-protein covalent complexes detection as the means for the assessment of the DNA damage induced by topoisomerase poisons. Topoisomerase II is essential cellular enzyme, which modifies the secondary structure of DNA. By introducing a temporary double strand break to DNA it relieves a structural tension raised during transcription and translation. Absolutely indispensable is the role of topoisomerase II in the separation of sister chromatids synthesized in the S-phase of the cell cycle. The mechanism of DNA cleavage involves a covalent bond formed between active site tyrosine and 5' phosphate on both of the DNA strands and through the formed break the other strand or the other DNA molecule can pass. After that, the DNA strands are rejoined and topoisomerase II is detached. The indispensability of topoisomerase II mainly for proliferating cells makes it a great target for the antineoplastic drugs and the molecules belonging to the class of topoisomerase II inhibitors (etoposide, anthracyclines) are amongst the most useful anticancer drugs in the clinical practice. These clinically used "topoisomerase...
13

Symetrické aminofosfináty / Symmetrical aminophosphinates

Procházková, Soňa January 2012 (has links)
Title: Symmetrical aminophosphinates Author: Bc. Soňa Procházková Department of Inorganic Chemistry, Faculty of Science, Charles University Supervisor: RNDr. Vojtěch Kubíček, Ph.D. Supervisor's email address: kubicek@natur.cuni.cz ABSTRACT Two types of α-aminophosphinates were prepared and studied: phosphinate analogues of iminodiacetic acid − aminobis(methyl(hydroxymethyl)phosphinic acid) (IDPhm ) and aminobis(methyl(2-carboxyethyl)phosphinic acid) (IDPce ), and bis(aminomethyl- phosphinates) − (hydroxy(fenyl)methylen)bis(aminomethylphosphinic acid) (PheOHABPin) and (methylen)bis(aminomethylphosphinic acid) (ABPin). All prepared compounds were fully characterized (by NMR, MS, elemental analysis). One crystal structure was determined by X-ray singlecrystal analysis. The diphosphinates were synthesized by Mannich type reaction, whereas the bis(aminomethylphosphinates) were prepared by multistep synthesis including reactive silylesters. Compounds were prepared in moderate or good yields Acid-base and coordination properties of ligands were investigated and compared by potentiometric and NMR titrations. The values of protonation constants of aminogroups, which determine stability of complexes, showed surprising results. An extremely low basicity of nitrogen atom was found in diphosphinates. So, these compounds...
14

Komplexy derivátů 1,4,7-triazacyklononanu / Complexes of 1,4,7-triazacyclononane derivatives

Kubinec, Jan January 2019 (has links)
The aim of this thesis was to prepare monoamide of macrocycle H3NOTA, which was prepared by multiple step synthesis. Ligand was characterized by NMR, MS and X-ray difraction analysis. Acid-base properties were studied by potentiometric titrations. Four protonation constants pKa`s were found and these protonation constants are lower than pKa`s of H3NOTA. Coordination properties with selected metal ions from the first row of transition metal, metal ions of biological interest and with lithium ions were investigated by potentiometric titration. Stability constants show that monoethylamide derivative of macrocycle H3NOTA forms complexes with lower stability than diethylamide derivative of macrocycle H3NOTA. Stability constants for complexes which contains amide group are lower than for H3NOTA complexes. Kinetics of Ga3+ complexation was investigated at different pH by 71 Ga NMR. The rate constants of and half-lives of complexation were determined at pH = 1. The rate constant was higher and the half-life of complexation was shorter than for H3NOTA ligand. Key words: macrocyclic complexes, thermodynamic stability, formation kinetics, radiopharmaceutical
15

Využití částic oxidu titaničitého s fosfonáty v medicíně / Titaniun Dioxide - Phosphonate Assemblies as Medical Nanoprobes

Řehoř, Ivan January 2011 (has links)
Titanium Dioxide - Phosphonate Assemblies as Medical Nanoprobes Ivan Řehoř PhD. Thesis Abstract: Multimodal imaging-therapeutic nanoprobe TiO2@RhdGd was prepared and successfully used for in- vitro and in-vivo cell tracking as well as for killing of cancer cells in-vitro. TiO2 nanoparticles, 12 nm in diameter, were used as a core for phosphonic acid modified functionalities, responsible for contrast in MRI and optical imaging. The phosphonic acid derivatives, used for surface modification, allows for grafting extraordinarily high loads of irreversibly adsorbed molecules of both types in one step. The prepared probe shows very high 1 H r1 relaxivity value as well as relaxivity density value, both crucial parameters for its use in MRI. The presence of fluorescent dye in its structure allows for its visualization by means of fluorescence microscopy. The applicability of the probe was studied, using three living systems - mesenchymal stem cells, cancer HeLa cells and T-lymphocytes. The probe did not exhibit toxicity in any of these systems and its long time storage in a lysosomal compartment was confirmed. Labeled cells were successfully visualized in-vitro by means of fluorescence microscopy and MRI. Consequent visualization of labeled cells in-vivo by means of fluorescence microscopy was also achieved....
16

Makrocyklické komplexy s neuzavřenou koordinační sférou / Macrocyclic complexes with open coordination sphere

Jaroš, Adam January 2018 (has links)
The aim of this work was to synthesize and study acid-base and coordination properties of ligands bearing a neutral or negative charge on their pendant arms. Acid-base properties of two ligands and thermodynamic stability of their complexes with gallium, copper, and zinc ions were studied using potentiometry, UV-Vis and NMR. Solid state structure of one of the ligands and its complex with copper ion was studied using RTG structural analysis. Structure of complexes in solution was studied using methods of computational chemistry.
17

Koordinační vlastnosti ethylfosfonového derivátu TACN / Coordination properties of TACN ethylphosphonic derivative

Poláková, Zuzana January 2016 (has links)
Ligand NOTPOEt was synthesized. Protonation constants and stability constants of Cu(II), Zn(II), Ni(II) and Ga(III) complexes were determined by potentiometric titrations. Cu(II) complex was characterized by UV-VIS spectroscopy and formation of Ga(III) complex was studied by NMR spectroscopy. The work was aimed at characterisation of the ligand with respect to potential application in biomedical imaging techniques.
18

Studium termodynamických a kinetických parametrů interakcí oligomerních modelů DNK s organokovovými komplexy aktivními v protirakovinné léčbě stanovených metodami kvantové chemie a kombinovanými QM/MM metodami / Studium termodynamických a kinetických parametrů interakcí oligomerních modelů DNK s organokovovými komplexy aktivními v protirakovinné léčbě stanovených metodami kvantové chemie a kombinovanými QM/MM metodami

Matunová, Petra January 2015 (has links)
It has been proven that platinum and ruthenium complexes are active in anti- cancer treatment. Nowadays, the common chemotherapeutica have a lot of side effects, therefore, drugs with fewer negative impacts are intensively searched for. The first part of the thesis focuses on the study of cis-[Pt(NH3)2Cl2] (cisplatin, DDP) and four platinum potential anticancer agents PtCl2(diaminocyclohexane), PtCl2(NH3)(cyclohexylamine) (JM118), cis-[PtCl2(NH3)(piperidine)] and trans-[PtCl2(NH3)(thiazole)]. Thermodynamic and kinetic parameters of reac- tions of these complexes in semi-hydrated and fully-hydrated form with guanine were studied using QM methods. The reaction with guanine is the key process ini- tiating the anticancer activity. Analyses of electron density were performed at the B3LYP/6-311++G(2df,2pd) level of theory in IEF-PCM model. The second part of the thesis studies the reaction of the so-called 'piano stool' Ru(II) transition metal complex, [Ru(II)(η6 -p-cymene(nalidixic acid)(H2O)]2+ , first with guanine using QM methods and second with ds-DNA model using QM/MM methods. The reaction site, which is described by QM method, is two consecutive guanines and the Ru(II) complex. Analyses of thermodynamic and kinetic parameters, and electron density were performed at the B97D/6-31G* level of theory. All the...
19

Fosfonátové a fosfinátové deriváty dipicolylaminu / Phosphonate and phosphinate derivatives of dipicolylamine

Hlinová, Veronika January 2017 (has links)
The Diploma Thesis deals with preparation of one phoshonate and two phospinate derivatives of dipicolylamine. Dissociation constants of prepared ligands were determined by potentiometric and NMR titration. Coordination properties of the compounds were studied by combination of potentiometry and UV-VIS spectrophotometry. Stability constants of complexes with selected transition metal ions (Cu2+ , Ni2+ a Zn2+ ) and alkali-earth metals ions (Ca2+ , Mg2+ ) were calculated. Acid-base and coordination properties in the solid state were studied by X-ray diffraction on single-crystals.
20

Měďné komplexy s fosfinonitrilovými donory / Copper(I) complexes with phosphinonitrile donors

Horký, Filip January 2017 (has links)
Title: Copper(I) complexes with phosphinonitrile donors Author: Bc. Filip Horký Department: Department of Inorganic chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Abstract: Although coordination compounds with phosphinonitrile ligands are already well known, in the vast majority of these complexes these ligands coordinate as simple P-donors with their cyano groups acting as auxiliary substituents. This led us to synthesize and study a series of Cu(I) complexes with two isomeric phosphinonitrile donors, namely 2-(diphenylphosphino)benzonitrile (Lo ) and 2-(diphenylphosphino)benzonitrile (Lp ), with different ligand-to-metal ratios and possibly characterize further coordination modes offered by these hybrid donors. This work describes the preparation of phosphinonitrile complexes from the aforementioned ligands and simple copper(I) halides (CuX, X = Cl, Br, I), pseudohalides (X = CN) and from [Cu(MeCN)4][BF4]. The products were characterized by nuclear magnetic resonance, infrared spectroscopy and elemental analysis, mass spectrometry, and their solid-state structures were determined by single-crystal X-ray crystallography. In addition, luminescent properties of the Cu(I) complexes were studied and catalytic activity of selected complexes was tested in copper-catalyzed alkyne-azide cycloaddition...

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