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5 ABSTRACT Charles University, Faculty of Pharmacy in Hradci Králové Department of Organic and Bioorganic Chemistry Candidate: Petr Makaj Supervisor: PharmDr. Petr Matouš, Ph.D Title of Thesis: Synthesis of Ortho-Condensed Nitrogen Heterocycles Using Gold Complexes This diploma thesis is focused on the preparation of pyridopyridine derivatives using gold-catalyzed cyclizations. The synthesis is based on MBS-protected propargylamine, which after substitution with aryl using Sonogashira coupling reacts with tert-butyl (3- oxopent-4-ynyl)carbamate to form substituted 1,5-enyne. The enyne thus prepared then undergoes cycloisomerization using tris(2- furanyl)phosphinegold(I)chloride as a catalyst to form pyridopyridine. Substances with this scaffold can be further used to synthesize potentially biologically active structures. Keywords: gold catalysis, cyclization, pyridopyridine derivatives, 1,8-naphthyridine derivatives

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of organic and bioorganic chemistry Candidate: Bartoloměj Grobař Supervisor: PharmDr. Petr Matouš, Ph.D. Title of thesis: Synthesis and reactivity of enyns with terminal double bond This work focuses on synthesis of structures containing terminal vinyl moiety and their subsequent reactivity. We tested various approaches that lead to formation of enynes, which are then cyclized using gold complex catalyst into tetrahydropyridines. Both utilize the addition of propargylamine protected by 4-methoxybenzenesulfonyl group to substituted butynone and methoxyphenyl propiolates. Tetrahydropyridine molecules that are successfully created, are further derivatized forming polycyclic structures.

This thesis describes the synthesis, photophysical properties and biological profiling of several series of polycyclic hetero-fused 7-deazapurine nucleosides. Modified 7-deazapurine ribonucleosides display a variety of biological effects. Previously, small (hetero)aromatic rings-fused 7-deazapurine nucleosides show submicromolar cytostatic effects or antiviral activities. Thus, the two isomeric series of new benzothieno-fused deazapurine nucleosides were designed as the extended analogues to the cytotoxic thieno-fused nucleosides and hetero-analogues of antiviral naphtho-fused nucleosides. The goal of the first part of my work was to synthesize these target compounds. Key steps include Negishi coupling of zincated pyrimidine with iodobenzothiophene, thermal or photochemical cyclization, glycosylation and final diversification. The furyl and benzofuryl derivatives exerted moderate anticancer and anti-HCV activities. Most of the free nucleosides showed moderate to strong fluorescence, and the corresponding 2′-deoxyribonucleoside triphosphate was incorporated into modified DNA and their fluorescence properties were studied The tri- and tetracyclic fused nucleobases can be synthesized either by multistep heterocyclization approach or through cross-coupling of zincated pyrimidine with hetaryl halides,...

Charles University, Faculty of Pharmacy in Hradec Králové Department Department of Organic and Bioorganic Chemistry Candidate Mgr. Petr Matouš Supervisor prof. RNDr. Milan Pour, Ph.D. Titel of Doctoral Thesis Gold-Catalyzed Cyclizations of 1,5-Enynes This Ph.D. thesis deals with the development of gold(I)-catalyzed cyclizations of propargylamino acrylates (3-aza-1,5-enynes) in the presence of an external nucleophile. A library of tetrahydropyridines with an unusual hemiaminal ether functional group was thus prepared via the cyclization of a series of substituted enynes. The influence of the protective group as well as the substitution on the chemoselectivity of the reaction was demonstrated. The tetrahydropyridines were further utilized as precursors for the preparation of pharmaceutically important nitrogen heterocycles. The reduction of selected compounds furnished substituted piperidines, while Diels-Alder cycloaddition of alkenylated tetrahydropyridines gave rise to isoquinoline derivatives. Additional ortho-fused heterocycles (furopyridine, pyrrolopyridine and chromenopyridine) were prepared by the intramolecular version of the cyclizations of enynes with pending internal nucleophiles.

Shigellosis is an acute diarrheal disease caused by enterobacteria of the genus Shigella. Worldwide, these bacteria are responsible for about 1 million deaths out of 165 million cases of the disease yearly, of which children under the age of 5 from developing countries are the most vulnerable group. The enzyme tRNA-guanine transglycolase (TGT for short) has been identified as essential for the effective pathogenesis of Shigella bacteria and therefore becomes a potential target for the selective treatment of shigellosis. This bachelor thesis describes the optimization of the preparation of a key intermediate for the synthesis of potential TGT inhibitors based on 8-aryl-9-deazaguanine structure. The synthesis starts from commercially available 2,6-dichloro-9-deazapurine. The main steps of the synthesis are the hydrolysis at position 6, the nucleophilic aromatic substitution of the chlorine group for the amino group in position 2, further the iodation and the introduction of the 3-thienyl group in position 8 by Suzuki coupling.

Syntheses of two series of 2'-sugar-modified pyrimido[4,5-b]indole nucleosides were developed. The synthetic strategy was based on functional group transformations of the 2'-hydroxy group of the 3',5'-protected ribonucleoside. The key intermediate was prepared via stereoselective nucleobase anion glycosylation of the known 4,6-dichloropyrimido[4,5-b]indole nucleobase with 2,3-O-isopropylidene- 5-O-TBS-protected halogenose, subsequent deprotection under acidic conditions and protection of 3'- and 5'-hydroxy groups with Markiewicz reagent. Pyrimidoindole arabinonucleoside was then synthesized using a sequence of oxidation-reduction reactions of the 2'-hydroxy stereocenter. The synthesis of pyrimidoindole 2'-deoxy- 2'-fluororibonucleoside was achieved by stereoselective SN2 fluorination of the THP-protected arabinoside followed by acidic deprotection. For the biological activity testing, two series of 4-substituted arabinonucleosides and 2'-deoxy- 2'-fluororibonucleosides were synthesized employing nucleophilic substitution or Pd-catalyzed cross-coupling reactions.

Study of glycosylation reactions of base- and sugar-modified nucleosides was performed and some of the procedures were applied for the synthesis of pyrimido[4,5-b]indole nucleosides. Only 2′-deoxy-2′-fluoro-arabinonucleoside was successfully synthesized with nucleobase anion glycosylation. Series of 4-substituted derivatives of this nucleoside was prepared for biological activity testing.

Charles University in Prague, Faculty of Science Department of Organic Chemistry Ing. Yana Chernykh Sulfur-Based Reagents for Nucleophilic and Radical Introduction of Tetrafluoroethyl and Tetrafluoroethylene Groups Ph.D. Thesis Prague 2014 ABSTRACT This project was aimed at developing new methodologies for selective introduction of tetrafluoroethyl and tetrafluoroethylene groups into organic molecules. The study was focused on reactivities of fluorinated sulfones and sulfides as tetrafluoroalkylation reagents. In the Introduction part of the thesis, main aspects of organofluorine chemistry are outlined, illustrating beneficial effects of fluorine atoms on physical, chemical and biological properties of organic compounds. General synthetic methods for the selective introduction of fluorine atoms and fluoroalkyl groups to organic molecules are described. Particular attention is given to reactivity and applications of CF2CF2-containing compounds, indicating challenges in synthetic approaches toward tetrafluoroalkylation. The Results and discussion part describes reactivities of four new fluorinated organosulfur reagents as tetrafluoroethyl and tetrafluoroethylene building blocks. The application of these reagents as various carbanionic or radical synthons proved to be effective for the incorporation of CF2CF2...