National Repository of Grey Literature 81 records found  beginprevious72 - 81  jump to record: Search took 0.00 seconds. 
New ligands for magnetic resonance imaging; pH-sensitive probes
Táborská, Zdeňka ; Kotek, Jan (advisor) ; Kubíček, Vojtěch (referee)
TÁBORSKÁ, Z. New ligands for magnetic resonance imaging; pH-sensitive probes. Prague: Charles University in Prague, Faculty of Science, Department of Inorganic Chemistry, 2011, 32 pages. Supervisor: doc. RNDr. Kotek J., Ph.D. Magnetic resonance imaging is a modern method used in diagnostic for assessing morphology and pathology of soft tissues. This thesis briefly outlines the principles of magnetic resonance imaging, including instrumentation. In many cases intravenously administered contrast agents are used, which are used for diagnostic purposes. At present, the most applied are CAs based on Gd(III) complexes. The experimental part of the thesis is focused on preparation of a derivative of DTPA with aminomethylphosphinate pendant group for using as a potential ligand for CAs for the magnetic resonance imaging. KEYWORDS: magnetic resonance imaging, contrast agents, lanthanides, phosphinates
Gallium complexes for molecular imaging of bone tissue
Holub, Jan ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
Title: Gallium Complexes for Molecular Imaging of Bone Tissue Author: Bc. Jan Holub Department of Inorganic Chemistry, Faculty of Science, Charles University Supervisor: RNDr. Vojtěch Kubíček, PhD. Supervisor's Email address: kubicek@natur.cuni.cz ABSTRACT This thesis is focused on preparing new ligands for selective complexation of gallium, which might serve as potential radiopharmaceuticals for 68 Ga-PET bone imaging. Two new ligands were prepared, combining 1,4,7-triazacyclonone-1,4-diacetic acid macrocyclic skeleton and bis(phosphonate) pendant arm, bound to the remaining free nitrogen atom on the macrocycle. Macrocyclic skeleton is responsible for high kinetic and thermodynamic stability of the Ga3+ complex and the bis(phosphonate) pendant arm insures selective delivery of the complex to the bone tissue. Both new ligands were fully characterized by NMR and mass spectroscopy. Complexation of Ga3+ was studied by 31 P and 71 Ga NMR spectroscopy. Binding to bone tissue was simulated by adsorption of the complexes to hydroxoapatite. Radiochemical experiments including study of 68 Ga complexation kinetics and basic in-vivo experiments including biodistribution studies and PET examination were done in cooperation with Johannes-Gutenberg Universität Mainz in Germany. Data obtained from these experiments were...
Complexes of 2,6-bis[(N-methylpiperazine-1-yl)methyl]-4-formyl phenol
Marečková, Vendula ; Vojtíšek, Pavel (advisor) ; Kubíček, Vojtěch (referee)
Thirteen new dinuclear complexes of ligand 2,6-bis[(N-methylpiperazine-1- yl)methyl]-4-formyl phenol (L1) were prepared. Copper(II) and palladium(II) salts were used for the syntheses. Following compounds were prepared: [Cu2L1(CH3COO)2]ClO4, [Cu2L1(CF3COO)2(ClO4)][Cu2L1(CF3COO)2]ClO4, [Pd2L1(CH3COO)3], [Pd2L1(CF3COO)3], [Pd2L1(Cl)4]. These ones should act as anion receptors. The acetates were exchanged for phenylphosphinates in the case of the complex cation [Cu2L1(CH3COO)2]+ and the structure of [Cu2L1(phPO2H)2]ClO4 was obtained. Geometry of coordination shell of Cu2+ - ions in prepared complexes is tetragonal pyramid. The UV-VIS spectroscopy was used for study of interactions in system of the ligand - metal - anion. Interactions between the ligand and metals in oxidation state 2 were observed as well as interactions between the complex [Cu2L1(CH3COO)2]ClO4 and sodium salts.
Symmetrical aminophosphinates
Procházková, Soňa ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
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...
Bis(phosphinates)
Křečková, Pavlína ; Kubíček, Vojtěch (advisor) ; Schulz, Jiří (referee)
Title: Bis(phosphinates) Autor: Pavlína Křečková Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: RNDr. Vojtěch Kubíček, Ph.D. Supervisor's e-mail address: kubicek@natur.cuni.cz Abstract Four geminal bis(phosphinate) acids were prepared and characterized by TLC, NMR, MS, EA. The compounds were acquired in high yields (over 55 %). Stability of these compounds was tested in chosen aqueous buffers, which covered a wide range of pH. The experiments showed that the prepared compounds are not fully stable. Performed experiments have shown negligible sorption of synthesized bis(phosphic) acids to hydroxyapatite, which was used as a model of bone tissue. Keywords: geminal, bis(phosphinate), decomposition, sorption.
Phosphinoferrocene amides and hydrazides
Solařová, Hana ; Štěpnička, Petr (advisor) ; Kubíček, Vojtěch (referee)
Title: Phosphinoferrocene amides and hydrazides Author: Hana Solařová Department: Department of Inorganic Chemistry Supervisor: doc. RNDr. Petr Štěpnička, Ph.D. Abstract: While studying functionalized phosphinoferrocene ligands, we recently turned to phosphinoferrocene carboxamides. These donors already proved to be versatile ligands for coordination chemistry and catalysis. This led us to synthesize and study the archetypal representative, 1'-(diphenylphosphino)-1-carbamoylferrocene (5), and the corresponding hydrazide 6. PPh2 COOH Fe Hdpf PPh2 CONH2 Fe 5 PPh2 CONHNH2 Fe 6 This work describes the preparation of primary amide 5 and hydrazide 6 from 1'- (diphenylphosphino)-1-ferrocenecarboxylic acid (Hdpf) via the corresponding acylbenzo- triazole derivative. The hydrazide was alternatively obtained from Hdpf methylester and hydrazine hydrate. Both newly synthesized compounds were characterized by spectroscopic methods (NMR, IR, and MS) and elemental analysis, and their crystal structures were determined by single-crystal X-ray crystallography. The amide was further utilized in the preparation of several palladium complexes, which were characterized in a similar manner including X-ray crystallography. One palladium complex was obtained also from the hydrazide. However, the hydrazide was used mainly as a...
Synthesis of alkylphosphinic acids
Procházková, Soňa ; Vojtíšek, Pavel (referee) ; Kubíček, Vojtěch (advisor)
The preparation of methylphosphinic acid and (3-terc-butoxy-3-oxopropyl)phosphinic acid using reaction between bis(trimethylsilyloxy)phosphine (BTSP) and iodomethane or tert-butyl acrylate was investigated. BTSP was generated in situ from ammonium phosphinate and hexamethyldisilazane. Simultaneously, the preparation of BTSP using N,O-bis(trimethylsilyl)acetamide was optimilized. The effect of conditions of the alkylation and addition reactions on the yield of monosubstituted and disubstituted phosphinic acids was examined. Furthemore, the preparation and properties of the BTSP-borane adduct and its possible employment in H-phosphinic acid syntheses were explored KEYWORDS: Organophosphorus synthesis, silylesters, borane adducts.
Methylene-bis(phosphonate) derivatives for modification of biomolecules
David, Tomáš ; Lorenc, Miroslav (referee) ; Kubíček, Vojtěch (advisor)
5 Title: Methylene-bis(phosphonate) Derivatives for Modification of Biomolecules Author: Tomáš David Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: RNDr. Vojtěch Kubíček, Ph.D. Supervisor's e-mail address: vvvojta@seznam.cz Abstract The aim of this work was to prepare derivatives of methylen-bis(phosphonic) acid. Thirty compounds (from which 29 are new) were prepared with moderate or good yields. All compounds were fully characterized by NMR and MS. Four new crystal structures were obtained by RTG monocrystal analysis. Derivative containing 4-nitrobenzyl group in the side chain was used for study of bis(phosphonates) adsorption parametres to hydroxyapatite (with quantification by UV-Vis spectroscopy). Several derivatives containing characteristic functi- onal groups (-NH2, -COOH, -NCS) were prepared. These compound are suitable for further derivatization, mainly for conjugation with more complex structures through amide bond or thiourea bridge. Conjugates of building blocks with fluorescent probe (fluorescein and dansyl) were prepared for potencial optical imaging. Further modification of one of the dansyl derivative afforded trifunctional molecule - contating bis(phosphonate) as a vector for a bone tissue, a fluorescent probe for a possible fluorescent imaging and a free...

National Repository of Grey Literature : 81 records found   beginprevious72 - 81  jump to record:
See also: similar author names
5 Kubíček, Václav
Interested in being notified about new results for this query?
Subscribe to the RSS feed.