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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.
121

Syntéza izotopově značeného ketaminu / Synthesis of isotopically labeled ketamine

Stuchlíková, Lucie January 2011 (has links)
In this work were synthesized ketamine isotopomers. Ketamine is used in human medicine and veterinary sectors. It has very broad spectrum of pharmacological effects: anesthetic, analgesic, hallucinogenic, bronchodilator, cardiovascular and antidepressive, which is currently in the research. At first was synthesized precursor of ketamine, N- desmethylketamine which was subsequently labeled the deuterium, tritium and carbon- 14. For the determination of purity and identity mass spectrometry and nuclear magnetic resonance spectroscopy were used. KEY WORDS synthesis of ketamine, ketamine, N-desmethylketamine, nor-ketamine, isotopically labeled ketamine, deuterium, tritium, carbon-14.
122

Příprava a vlastnosti moderních magnetoelektrických a multiferoických keramických materiálů / Processing and properties of novel magnetoelectric and multiferroic ceramic materials

Osička, Luděk January 2013 (has links)
A literature review on the topic of ferroic and multiferroic solid solutions of BaTiO3, SrTiO3 and EuTiO3 forms the first part of this master thesis. The second part describes the experimental preparation and evaluation of the properties of samples of europium strontium titanates - EuxSr1-xTiO3. First, the high temperature solid state synthesis was carried out and relative density and open porosity of the sintered samples were evaluated. The sintered samples showed open porosity higher than 10%. The reasons for this behavior were evaluated and described from the point of view of experimental conditions and thermodynamical calculations. Finally, electric and dielectric properties of selected samples were measured. These results show that these samples are insulators and their residual conductivity is caused probably by oxygen vacancies, arising from the synthesis in a strongly reducing atmosphere of pure hydrogen.
123

Příprava nesymetrických derivátů DOTA a studium jejich komplexů / Synthesis of unsymmetric DOTA derivatives and study of their complexes

Obuch, Jakub January 2021 (has links)
Lanthanide(III) complexes are compounds with both diagnostic and therapeutic applications. For diagnostic applications, they are used as contrast agents for imaging techniques such as MRI, PET or SPECT. In therapy, complexes of beta or alpha particle- emitting radionuclides are used. If the complexes contain protonable groups, their behaviour is dependent on pH of the solution. Protonation of these groups should occur close to the physiological pH. If the efficiency (relaxivity) of the MRI contrast agent is dependent on protonation state, this method can be used for determination of pH of tissues in vivo. For radiopharmaceuticals, fast complexation of short-lived metal radionuclides is important and protonation might significantly accelerate the complex formation. For therapeutic applications, possibility of labelling at low temperatures when heat-sensitive biovectors (e.g. antibodies) do not decompose. To assess the effect of protonation of amino group in the vicinity of the metal ion, amino-bis(phosphinate) pendant arm was proposed, where the dissociation constant of the amino group below the physiological pH can be expected. Three ligands containing this group and DO3A fragment were prepared and their complexes were studied to assess aforementioned possible uses in medicine. Their structure and...
124

Využití B-H karbonátů v organokatalytických transformacích / The use of BH carbonates in organocatalytic transformations

Tichá, Iveta January 2014 (has links)
This diploma thesis is focused on the preparation of enantiomerically pure compounds based on organocatalytic allylic substitution using Baylis-Hillman carbonates. As selected substrates for the allylic substitution were chosen α-azidoketones such as azidoacetophenone, 2-azido-1-indanone and then heterocyclic compounds (N-phenylrhodanine and its derivate) belonging to the pharmaceutical privileged compounds. Other substrate for allylic substitution was allylmalononitrile. In addition, this thesis includes with synthesis of cyclic compounds based on the reaction of products of allylmalononitrile with B-H carbonates using olefin metathesis.
125

Enantioselektivní syntéza spirocyklických sloučenin / Enantioselective synthesis of spiro compounds

Urban, Michal January 2014 (has links)
This thesis deals with the preparation of enantiomerically and diastereomerically pure spirocompounds using asymmetric organocatalysis. The first part is focused on the enantioselective synthesis of spirocompounds by organocatalytic reaction of α,β-unsaturated aldehydes with sulfur heterocyclic compounds catalysed with secondary amines. It is a domino Michael/Michael/aldol reaction using iminium and enamine activation. The second part is focused on the subsequent transformation of the prepared spirocompounds.
126

Využití organokatalytických reakcí pro přípravu funkcionalizovaných cyklických sloučenin / Organocatalytic reactions leading to functionalized cyclic compounds

Formánek, Bedřich January 2014 (has links)
First part is focused on finding suitable reaction conditions for organocatalytic domino Michael/Michael reaction of ethyl (E)-3-(2-thiophenyl)acrylate with α,β-unsaturated aldehydes. Second part deals with the preparation of pyrazolone derivatives from commercially available compounds and describes effects of various substituents in α-position on chemical efficiency and stereoselectivity of amination with azodicarboxylate catalyzed by quinine.
127

Syntéza a vlastnosti neuroaktivních steroidů / Synthesis and Properties of Neuroactive Steroids

Kapras, Vojtěch January 2016 (has links)
Herein is reported the synthesis of molecular probes for action of neuroactive steroids in vitro and in living organisms. In the first part, preparation of enantiomeric pregnane steroids is investigated, ultimately resulting into the total synthesis of ent-progesterone. The chirality of the target molecule is introduced by a highly effective organocatalytic asymmetric Robinson annulation. A new method for the sequential construction of five-membered carbocyclic ring is introduced as the key step. This is composed of substrate-controlled copper-catalyzed conjugate addition followed by radical oxygenation and subsequent thermal cyclization employing the persistent radical effect. The synthesis of truncated neurosteroid analogs is described and their biological activity at the NMDA receptor is compared with the native hormone. In the second part, methodology for specific deuterium labeling of both angular methyls of the 5β-pregnane steroid core is explored. Special attention was paid to the Barton-McCombie deoxygenation as the tool for introduction of the last deuterium atom into the methyl group. Both positions were labelled with total of three deuterium atoms in high isotopic purity.
128

Vliv příjmu proteinů (aminokyselin) na syntézu svalových bílkovin po silovém tréninku / Effect of protein (aminoacid) ingestion on muscle protein synthesis following resistance exercise

Juřík, Roman January 2017 (has links)
Title: Effect of protein (amino acid) ingestion on muscle protein synthesis following resistance exercise. Purpose: The main objective of this thesis is to verify the three basic factors of the amount, type and timing of protein intake based on scientific studies and literature, to provide the most objective and accurate information and procedure on the methodology of nutrition and supplementation associated with the intake of protein / amino acids after strength training and how it all affects muscle synthesis. Summery: The theoretical part of the thesis, discusses the factors affecting muscle protein synthesis, which stimulate growth and tissue regeneration, based on optimal stress response. Logically, it starts from general, i.e. the explanation of terms such as muscle tissue, the stimulation of muscle tissue and its manifestations and changes, nutrition factors and muscle stimulation, the mechanism of dietary factors (proteins/amino acids), specificity of protein/ amino acids in their application to answer the three key issues, which are summarized in the section named scientific studies, which focuses on the effect of intake of protein/ amino acids, in relationship to the efficiency of protein synthesis after strength training. The section summarizes, in detail, the questions of timing,...
129

Vliv příjmu proteinů (aminokyselin) na syntézu svalových bílkovin po silovém tréninku / Effect of protein (aminoacid) ingestion on muscle protein synthesis following resistance exercise

Juřík, Roman January 2017 (has links)
Title: Effect of protein (amino acid) ingestion on muscle protein synthesis following resistance exercise. Purpose: The main objective of this thesis is to verify the three basic factors of the amount, type and timing of protein intake based on scientific studies and literature, to provide the most objective and accurate information and procedure on the methodology of nutrition and supplementation associated with the intake of protein / amino acids after strength training and how it all affects muscle synthesis. Summery: The theoretical part of the thesis, discusses the factors affecting muscle protein synthesis, which stimulate growth and tissue regeneration, based on optimal stress response. Logically, it starts from general, i.e. the explanation of terms such as muscle tissue, the stimulation of muscle tissue and its manifestations and changes, nutrition factors and muscle stimulation, the mechanism of dietary factors (proteins/amino acids), specificity of protein/ amino acids in their application to answer the three key issues, which are summarized in the section named scientific studies, which focuses on the effect of intake of protein/ amino acids, in relationship to the efficiency of protein synthesis after strength training. The section summarizes, in detail, the questions of timing,...
130

Strategická analýza podniku / Strategic Analysis of an Enterprise

Pevný, Robert January 2011 (has links)
This diploma thesis deals with the strategic analysis of Skoda Auto a. s. and its current strategy. Also, it deals with verifying of given hypotheses to effectively determine the future operational strategy. The first part is the theoretical and methodological, which explains the key concepts of strategic analysis of a company. It's followed by the practical part, which translates the theory of strategic analysis into the practice, analyzes modern trends and via the synthesis method it achieves the objective of this thesis: to specify strategic recommendations for Skoda Auto and to verify the hypotheses specified in the beginning.

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