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Study of porphyrins substituted wich glycosylated steroids
Zelenka, Karel ; Trnka, Tomáš (advisor) ; Jindřich, Jindřich (referee) ; Kefurt, Karel (referee) ; Pouzar, Vladimir (referee)
I I 4. Conclusions This work is focused on syntheses of new zeso-substituted porphyrins containing glycosylated-steroid moieties and study oftheir physico-chemical and supramolecular propertres. In the first part oť this work, procedure for the synthesis of B glycosides 4 or 5 is described. No ťormation of ortohoesters was observed. Next part of this work consists oť searching for suitable protecting group for a saccharide part oť molecule and preparation of steroidaldehydes.Protectedglycosides10, ll,tó, 17,|9a+l9band20wereprepared.Suitable method for preparation ofaldehydes 14, 15, 23,24,29,30 an.34 is described (chapter 3.1). Following part of work describes preparation of porphyrins with protected sugar moiety. Symmetrical Al type porphyrins 35-41 were prepared. Also preparatio n of trans-A2ts1 ýpe porphyrins 43, 44 and A]B type 45, 4ó is described. Preparation oť porphyrins 47.50 with deprotected hydroxyl groups is described (Chapter 3.2). Solvent driven aggregation behavior oť the porphyrins was studied in aqueous solvent mixtures' Formation of aggregates of porphyrin 45 was proved using uv-vis spectroscopy (Chapter 3.3). Considering use oť prepared porphyrins in electrochemistry as a possible electrochemical sensors, polarographic and voltametric studies oť porphyrins 47-19 were per|ormed and showed...
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Preparation of bifunctional organocatalysts
Rohaľová, Dominika ; Veselý, Jan (advisor) ; Trnka, Tomáš (referee)
This bachelor thesis deals with the synthesis of bifunctional thiourea catalysts and corresponding building blocks derived from levoglukosane. The first part was of this thesis is focused on the preparation 1,6:2,3-dianhydro-4-azido-4-deoxy-β-D-mannose. The second part of the thesis is deals with the preparation od bifunctional catalyst. Keywords Asymmetric synthesis, organocatalysis, saccharides, bifunctional calatysts, thiourea, morpholine.
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Synthesis of cycles using organocatalysis and catalysis with metal complexes
Hurný, David ; Veselý, Jan (advisor) ; Trnka, Tomáš (referee)
This thesis deals with an enantioselective synthesis of cyclic compounds by using a combination of organocatalysis and transition metal catalysis. The thesis deals mainly with usage of aminocatalyst for activation of aldehydes and copper catalyst for activation of terminal triple bond. The first part is focused on the preparation of starting compounds for cyclizations (α-oxoesters, α- substituted nitroalkanes and α-substituted aldehydes). The second part concerns carbocyclization itself and optimization of reaction conditions to achieve highly stereoselective reaction. Powered by TCPDF (www.tcpdf.org)
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Chemical experiments with natural compounds oriented on education.
Opatová, Michala ; Petrželová, Simona (advisor) ; Trnka, Tomáš (referee) ; Svoboda, Lubomír (referee)
Inclusion of experiments into tuition of chemistry is required and a topic of natural compounds enables combination of chemistry with biology and subjects of common life. This dissertation concerns experiments with natural compounds, their utilization within project education at educational and popularizing events which are held by Charles University in Prague. Researches of selected secondary textbooks and professional publications are parts of the thesis. A questionnaire survey is also included on which basis opinions of secondary teachers were evaluated. A collection of instruction in the experiments was prepared. The main part of the thesis is focused on detailed desription of experiments supplemented with pictures and information about selected natural compounds. A proposal to educational excursions focused on natural compounds and project tuition is also included. The whole thesis bring a new look into experiments with natural compounds in sense of searching individual compounds in blends, discovering composition of food processing products not only by chromatography.
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Difference between czech media's relation to Africa and the rest of the world on the example of formation of independent Kosovo and South Sudan
Trnka, Tomáš ; Závozda, Petr (advisor) ; Hanzal, Jaromír (referee)
The bachelor thesis "Difference between Czech media's relation to Africa and the rest of the world on the example of formation of independent Kosovo and South Sudan is analysing the approach of four major broadsheets to Africa. The thesis is using a quantitative content analysis in order to describe characteristics of the international news in the chosen broadsheets during two different months. The recived data will be then confirmed by analysing a specific case of independent Kosovo and South Sudan. In the first half, the thesis is focusing on a brief description of recent history of both states which will be analysed later on. The historical background will help to understand the situation in both countries which as in information that will be used to analyse the articles in the observed period. In the theoretical part, some concepts of media theory are presented as well as they are used throughout the thesis. In the second half, the methodology is presented in order to detrmine a plan which will be followed during the analysis. In this chapter, the hypothesis is clearly described. In the next step, the analysis itself is presented in a form of graphs and commentary. The final chapter analyses the recived data and confirms whether the hypothesis was correct. Also the results are linked to the...
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Synthesis of novel types of C-nucleosides
Kubelka, Tomáš ; Hocek, Michal (advisor) ; Trnka, Tomáš (referee) ; Moravcová, Jitka (referee)
of PhD Thesis: Synthesis of novel types of C-nucleosides General and modular approach for the preparation of disubstituted pyrimidine and pyridine C-2'-deoxyribonucleosides and benzyl homo C-ribonucleosides was developed. The key intermediate 2,4-dichloropyrimidine C-2'-deoxyribonucleoside was efficiently prepared from easily available TBS-protected deoxyribose glycal in three steps. Its mild nucleophilic substitutions or cross-coupling reactions proceeded regioselectively at position 4, while at elevated temperatures or with excess of reagent, a double substitution occurred. The 2-chloro-4-substituted intermediates underwent another substitution or coupling to afford a two-dimensional library of diverse 2,4-disubstituted pyrimidin-5-yl C-2'-deoxyribonucleotides. Modular methodology for the synthesis of 2,6-disubstituted pyridine C-2'-deoxyribonucleosides was based on the Heck coupling of bromo-chloro-iodopyridines with TBS-protected deoxyribose glycal. Obtained 2-bromo-6-chloro- and 6-bromo-2-chloropyridin-3-yl deoxyribonucleosides were used for further transformations. Some of their Pd-catalyzed cross-coupling reactions proceeded chemoselectively at the position of the bromine, whereas nucleophilic substitutions were unselective and gave mixtures of products. The mono- substituted intermediates...
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Preparation of organocatalysts derived from monosaccharides
Nekvinda, Jan ; Veselý, Jan (advisor) ; Trnka, Tomáš (referee)
This bachelor thesis is focused on the synthesis of organocatalysts derived from monosaccharides, in particular D-glucose and D-glucosamine, with various protecting groups. Synthesis of various thiourea catalysts and the attempt to prepare new squaramide catalysts is described. ABSTRAKT Tato bakalářská práce je zaměřena na syntézu organokatalyzátorů odvozených od monosacharidů, zejména z D-glukózy a D-glukosaminu, s různými chránícími skupinami. Dále je popsána syntéza různých thiomočovinových katalyzátorů a pokus o přípravu katalyzátoru obsahující derivát kyseliny čtvercové.
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Staudinger reaction of azides derived from levoglucosan.
Mitrovský, Ondřej ; Trnka, Tomáš (advisor) ; Řezanka, Michal (referee)
This bachelor thesis is focused on research of reactivity of azido derivatives of levoglucosan with triphenylphosphine and tris(pyrrolidine)phosphine. The ultimate goal of this thesis was preparation of until now unpublished phosphazenes to make them available for practical utilization. Two of them were successfully prepared in crystallic form. Better results were with 2- or 4-azido derivatives of levoglucosan. In general reactivity of anhydro derivatives with azido group at C-3 were substantially lower, moreover the product mostly failed to crystallize.
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