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Application of amines for the preparation of chiral cyclic compounds
Formánek, Bedřich ; Veselý, Jan (advisor) ; Kočovský, Pavel (referee) ; Soural, Miroslav (referee)
Organocatalysis, along with catalysis by metal complexes or enzymes, has become one of the very useful tools of asymmetric synthesis. Different activation modes or their combinations into sequences (domino reactions) enable effective access to enantiomerically enriched complex substances. The objective of this work was the preparation of chiral molecules from simple precursors activated by amine-based organocatalysts. In particular, we were focused on a study of asymmetric allyl substitution of Morita-Baylis-Hillman carbonates and two-component domino reactions on sulfur-containing heterocycles. The thesis deals with the organocatalytic allyl amination of Morita-Baylis-Hillman carbonates with aromatic amines catalyzed by β-isocupreidine. The corresponding allylic amines were obtained in high yields (90-96%) with moderate enantiomeric excess. It was possible to get substances of high optical purity (ee 82-99%) by recrystallization of selected products. Furthermore, the developed method was applied in the preparation of enantiomerically enriched β-lactams, which represent valuable precursors, for example, in the synthesis of the drug Ezetimibe. The second part of the work is focused on stereoselective cyclization reactions comprising selected sulfur heterocycles. Although the cyclization reaction of...
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Carbapenemases and their molecular genetic detection in bacteria causing severe hospital acquired infections
Vavrová, Jolana ; Dřevínek, Pavel (advisor) ; Zikánová, Blanka (referee)
The aim of this study is to characterize β-lactamases that hydrolyze carbapenems. They belong to molecular classes A, B and D and their new variations are still being identified. The production of enzymes hydrolyzing β-lactam antibiotics is common among Gram-negative bacteria which include also serious nosocomial pathogens such as Pseudomonas aeruginosa, Acinetobacter baumannii or members of Enterobacteriaceae family. The importance of the carbapenemases in clinical practice underlines the fact that carbapenems are broad-spectrum antibiotics, which are considered the reserve antibiotics. An increase in the number of cases of the carbapenem resistance is caused mainly by spread of genes encoding carbapenemases. Detection of carbapenemases and surveillance of their occurrence are both essential not only for optimal management of patients' care, but also for control of the spread of bacterial strains producing carbapenemases.
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Carbapenemases and their molecular genetic detection in bacteria causing severe hospital acquired infections
Vavrová, Jolana ; Dřevínek, Pavel (advisor) ; Zikánová, Blanka (referee)
The aim of this study is to characterize β-lactamases that hydrolyze carbapenems. They belong to molecular classes A, B and D and their new variations are still being identified. The production of enzymes hydrolyzing β-lactam antibiotics is common among Gram-negative bacteria which include also serious nosocomial pathogens such as Pseudomonas aeruginosa, Acinetobacter baumannii or members of Enterobacteriaceae family. The importance of the carbapenemases in clinical practice underlines the fact that carbapenems are broad-spectrum antibiotics, which are considered the reserve antibiotics. An increase in the number of cases of the carbapenem resistance is caused mainly by spread of genes encoding carbapenemases. Detection of carbapenemases and surveillance of their occurrence are both essential not only for optimal management of patients' care, but also for control of the spread of bacterial strains producing carbapenemases.
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