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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

Syntéza antimikrobiálních látek na bázi derivátů salicylové kyseliny / Synthesis of antimicrobial compounds based on derivatives of salicylic acid

Tvrdý, Václav January 2016 (has links)
Schiff bases are widely used both in technical practice and in the field of medicine. For their antimicrobial activities are studied as potential antimacterial and abtifungal drugs. With increasing level of resistence to currently drugs is the development of new substances very intense. Salicylanilides are a group of substances with antimicrobial activity and are also intensively studied. Based on that we were synthesized novel Schiff bases resulting from salicylic acid, respectively salicylanilides. It was concretely prepared five compounds: 5- chloro-N-{4-[phenyl(phenylimino)methyl]phenyl}-2-hydroxybenzamide, 5-bromo-N-{4-[ phenyl(phenylimino)methyl]phenyl}-2-hydroxybenzamide, 5-chloro-N-{4-[phenyl(3- chlorfenylimino)methyl]phenyl}-2-hydroxybenzamide, 5-chloro-N-{4-[phenyl(4- chlorfenylimino)methyl]phenyl}-2-hydroxybenzamide, 5-bromo-N-{4-[phenyl(4- chlorfenylimino)methyl]phenyl}-2-hydroxybenzamide. The reaction proceeded at the boiling point of the solvent, with catalytic amount of p-toluensulfonic acid. Most of the compounds were characterized by IR, H1 NMR, C13 NMR and melting point. The prepared compounds showed E/Z isomers on double bond, it is demonstrated on NMR specters.
12

Analýza řízení kvality v energetické firmě s cílem návrhu opatření vedoucí ke snížení vadných dodávek

Benáček, Roman January 2015 (has links)
The subject of this thesis is the analysis of quality management in energy company in order to draft measures to reduce defective deliveries. The thesis is processed using the methodology of the project and expert engineering, methods of quality management, standards, regulations and laws with the result leading to a reduction in the number of disagreements in the input quality control of various supplies of goods.
13

Režie jako pohyblivá role / The Director as a Shifting Role

Burianová, Zuzana January 2015 (has links)
The present master's thesis focuses on relationships between the director and the other creators of a theatre production and on the ways in which these relationships develop during the creative process. The author describes and reassesses specific practical examples from her directorial and dramaturgical experience in years 2012-2015. The first part is devoted to those productions in which the author collaborated also on the playtext. It seeks to identify specific primary impulses which had inspired individual projects and to track any subsequent evolution of these impulses, a process which the author defines as assignment formulation. The second part concentrates in more detail on collaboration with actors and explores the circumstances in which a free creative process can be established, the border between the actor's creation and the director's direction of the actor. The third part addresses the interaction between three theatre professions, namely the director, the dramaturgist and the set designer.
14

Syntéza derivátů haemanthaminu / Synthesis of haemanthamine derivatives

Marková, Jana January 2017 (has links)
6 Abstract Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Jana Marková Supervisor: doc. Ing. Lucie Cahlíková, Ph.D. Title of Diploma thesis: Synthesis of haemanthamine derivatives Based on previous studies, the haemanthamine alkaloid showing remarkable antitumorous activity was chosen as the subject of this thesis. The purpose of the thesis was preparation of its more active derivatives, namely esters. Preparation concerns the following derivatives: 11- O- butanoylhaemanthamine, 11-O-(3,4-dimethoxybenzoyl)-haemanthamine, 11-O-(4- trifluoromethoxybenzoyl)-haemanthamine, 11-O-isobutanoyhaemanthamine. These were created by the reaction of haemanthamine and the relevant acilating agent (acylchloride, anhydride) in the environment of anhydrous pyridine or tetrahydrofuran with adding dimethylaminopyridine as a catalyst. Most of the products were obtained in the form of colourless oil, one of the substances crystallized into white amorphous crystals. However, during an attempt of dioxolane ring opening, the preparation of 3-demethylhaemanthamine derivative proved unsuccessful. Prepared derivatives were mostly identified by EI-MS and NMR. All the substances were gained in sufficient outcomes in the scale of 43 - 81 %. All the compounds were...
15

Modifikované peptidy ve spojení s kvantovými tečkami

Janů, Libor January 2013 (has links)
In this study, water soluble CdTe QDs of different emission wavelengths were prepared. Microwave synthesis was used to prepare CdTe QDs coated with mercaptopropionic acid (MPA). MPA ensures biocompatibility and good water solubility of QDs. Therefore QDs can be used directly in bioanalytics. Further, QDs modified with biotinylated glutathione (GSH) were prepared. In this case mercapto group (--SH) ensures a bonding of GSH to QDs surface and biotin serves as high specific linker for streptavidin, avidin or neutravidin modified analyte. Finally, peptide mediated immuno-quantum dots were prepared. CdTe QDs were coated with heptamer HWRGWVC which is able to bind Fc region of human immunoglobulin G.
16

Aminofosfinové kyseliny / Aminophosphinic acids

Kruliš, Tomáš January 2015 (has links)
Two phosphinic acids were prepared: 1-hydroxy-ethan-1,1-bis[N,N- bis(karboxymethyl)aminomethyl]phosphinic acid; H6L1 and methylenebis[N,N- bis(karboxymethyl)aminomethyl]phosphinic acid; H6L2 . Acid-base and complexation properties were studied by potenciometric titrations. Complexes of both ligands with Cu2+ ions were studied in detail using UV/VIS spectrometry. Keywords: Organophosphorus synthesis, bisphosphinic acids, coordination properties
17

Příprava benzoylovaných derivátů cyklodextrinů / Preparation of benzoylated derivatives of cyclodextrins

Jůza, Radomír January 2017 (has links)
This master thesis deals with the preparation of the cyclodextrin (CD) derivatives that are suitable for complexation of the electron-rich aromatic compounds such as helicenes. The basic skeleton of native CD was perbenzoylated in all positions 2, 3 and 6 in the first place. Then the nucleophilic attack of carboxylates of benzoic acids with electron- withdrawing groups (NO2) or electron-donating group (NH2) to per(6-deoxy-6-iodo)-CD derivatives were used to prepare the perbenzoylated CD derivatives in the postition 6. Binding constant was determined for the prepared benzoylated derivatives of CD and the racemate of the hexahelicene using the NMR titration. Perbenzoylated derivatives of β-CD in all position 2,3 and 6 with one azido group in position 6 were prepared as well. These derivatives could be covalently bonded as chiral selectors in the stationary phase for the HPLC separation of aromatic enantiomers. Keywords: cylodextrins, persubstitution, benzoyl, 4-nitrobenzoyl, 3,5-dinitrobenzoyl, helicenes, NMR titration, binding constants
18

Syntéza nových látek s potenciálním radioprotektivním účinkem / Synthesis of novel compounds as potential radioprotectives

Živná, Natálie January 2021 (has links)
Harmful substances polluting the environment, including ionizing radiation, and an unhealthy lifestyle are responsible for the increased incidence of cancer. The projected outlook for the next ten to twenty years suggests an increase of 63% in newly diagnosed cases of cancer annually. Radiotherapy is an important component of cancer treatment, given approximately to 50% of all cancer patients. Despite ongoing advances in the methods of radiotherapy, quality of life continues to be lowered as a result of the radiation treatment. Novel strategies towards improvement need to be adapted, such as the use of radioprotective substances. The goal of this thesis is to synthesize novel radioprotective agents based on the 1-(2- hydroxyethyl)piperazine moiety targeting the intrinsic apoptotic pathway, therefore protecting healthy tissue from ionizing radiation.
19

Geminální bis(fosfináty) / Geminal bis(phosphinates)

David, Tomáš January 2014 (has links)
Slow complexation is one of the major limitations of current macrocyclic chela- tors utilized in nuclear medicine for complexation of metal radionuclides. This property can be improved by ligand design. Among metal radioisotopes, the copper ones (e.g. 60Cu, 61Cu, 62Cu, 64Cu and 67Cu) have become commonly available in recent years and cyclam-derived ligands are the most suitable ligands for Cu2+ complexation. To alter the complexation rate, bis(phosphinic acid) group is promising unit as it is able to complex metal ions in acidic solu- tions. However, geminal bis(phosphinates) represent poorly studied group of compounds and, thus, it is challenging to uncover their properties. Several simple amino-bis(phosphinates) were synthesized and its acid-base and coordi- nation properties were studied. Unlike structurally similar geminal bis(phosphonates), the title compounds showed negligible adsorption onto hydroxyapatite (commonly used model of bone tissue). The obtained knowledge dealing with geminal bis(phosphinates) was utilized in synthe- sis of two novel cyclam derivatives. The ligands (bearing either one geminal bis(phosphinate) or one geminal phosphino-phosphonate pendant arm) were synthesized by highly efficient procedure. The corresponding Cu2+ complexes are formed with very high rates and show...
20

Syntéza a hodnocení lidských 6-hydroxyceramidů / Synthesis and evaluation of human 6-hydroxyceramides

Majcher, Adam January 2020 (has links)
Title of the Master thesis: Synthesis and evaluation of human 6-hydroxyceramides Candidate: Adam Majcher Supervisor: PharmDr. Lukáš Opálka, Ph.D. Consultant: PharmDr. Andrej Kováčik, Ph.D. Charles University, Faculty of Pharmacy in Hradec Králové Skin Barrier Research Group, Department of Organic and Bioorganic Chemistry Ceramides (Cer), the members of sphingolipid family, occur in all human cells and play an important role in cell signaling. In high concentrations, Cer can also be found in the uppermost layer of epidermis called stratum corneum, along with free fatty acids and cholesterol (in equimolar ratio), where they form the intercellular multi-lamellar lipid matrix. The key function of stratum corneum is to ensure a permeability barrier, thus, to provide water and electrolyte homeostasis, and to prevent entry of harmful substances into the organism. Cer are composed of a sphingoid base and an acyl part derived from a long-chain fatty acid. Cer based on 6-hydroxysphingosine (H) are amongst the most unusual sphingolipids. In contrast to sphingosine-based Cer, 6-hydroxysphingosine-based Cer (H-Cer) are unique for the epidermis and, in addition, H-Cer are not typical for all mammals. Moreover, the function and biosynthesis of H-Cer in the skin is still not completely understood. Several...

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