|
|
Application of Pd-Catalyzed Reactions to the Synthesis of Lactones
Šnajdr, Ivan ; Pour, Milan (advisor) ; Kotora, Martin (referee) ; Opletalová, Veronika (referee)
Within the framework of this Thesis, a method fot the preparation of 3,6- disubstituted pyranones was developed and 15 final lactones were synthesized, and their cytostatic and antifungal activity was investigated. Principal steps in the preparation of the compounds were Yamaguchi-Hirao alkylation, hydroalumination followed by iodation and Pd- catalyzed carbonylative lactonization. None of the target compounds displayed interesting cytostatic or antifungal activity (IC50 < 10 μmol/L), which was suprising given the significant antifungal activity of analogous butenolides. The development of the synthesis of 3- monosubstituted pyranones is described next. Our strategy is based on the use of 5,6-dihydro-2H- pyran-2-one as the starting material, which was converted into the 3-iodo-5,6-dihydro-2H- pyran-2-one in one step. The key step of the synthesis was Pd-catalyzed Suzuki coupling. Finally, the preparation of α- and β-substituted-γ-alkylidenepentenolides is described. The target compounds exhibited significant cytostatic activity (IC50 < 5 μmol/L) against all tested tumor cells (CCRF-CEM, HeLa S3, HT 29, HL 60, L 1210).
|
|
|
Azaphthalocyanines as new structural group of fluorescence quencher.
Kopecký, Kamil ; Doležal, Martin (advisor) ; Lang, Kamil (referee) ; Pour, Milan (referee)
1 SUMMARY This dissertation thesis deals with searching of structurally new non-fluorescent quenchers of fluorescence, which may be used for preparation of molecular probes. These potential quenchers are derived from asymmetrically substituted alkylaminoderivatives of tetrapyrazinoporphyrazines - azaphthalocyanines. As the part of this work is preparation of precursors - 5,6-disubstituted pyrazine-2,3-dicarbonitriles. They are starting material for the preparation of final substances - tetrapyrazinoporphyrazines bearing different functional moieties. In total were prepared: 14 intermediates (3 of them have been described in our department) 13 final tetrapyrazinoporphyrazines (1 of them has been described in our department) 1 modified solid phase suitable for synthesis of marked oligonucleotides 2 by-products 23 undescribed compounds were prepared. Synthesis of 4 substances was not successful. Final products were tested for their singlet oxygen quantum yields, stability in solutions used for synthesis of oligonucleotides and subsequently ability of quenching of commercially available fluorofor Cy5® . This ability was compared with commercially available quencher Black Hole Quencher-2® . As a part of this work is confirmation of distribution of congeners arising during the statistical tetramerization of...
|
|
|
Synthesis of Prolinol-Based Phosphonate Nucleotide Analogues
Vaněk, Václav ; Rosenberg, Ivan (advisor) ; Černý, Miloslav (referee) ; Moravcová, Jitka (referee) ; Pour, Milan (referee)
4. Conclusion A series ofnovel isosteric 3'-nucleotide analogues (9a-e and l0a-e) was synthesized, cr-t-- and B-t--prolinol nucleoside N-methylphosphonic acids distinguished for the loss of unambiguously defined configuration at the nitrogen atom in 3'-position of prolinol nng. Remarkable conformational differences between cr-L- and B-l-prolinol nucleotides determined by NMR study suggest some similarity with the natural 5'-o-nucleotide. The same conformational changes in o-series of prolinol nucleotides fit even better the 3'- and 5'-o- nucleotides. In addition, a series of four diastereoisomeric synthons 5-8 was prepared from the commercially available lrans-4-hydroxy-l-proline, giving access to a complete set of prolinol-derived nucleotide analogues bearing cr.L-, B-t--, o.o- and p-o-conÍiguration. In order to constrain the conformational flexibility of the N-phosphonomethyl moiety, seveÍal protected compounds were subjected to N-oxidation or N-methylation which gave chiral N-oxides or quatemary ammonium salts. However, the synthesis of the respective unprotected phosphonic acids was unsuccessful, probably due to their fast decomposition. Acylation ofthe pyrrolidine ring nitrogen atom by several acylphosphonic acid derivatives led to the novel N.phosphonoformyl, /y'.phosphonoacetyl and...
|
|
| |
|
|
Anti-adhesive activity of bovine whey oligosaccharides against Neisseria meningitis
Janůšová, Barbora ; Vávrová, Kateřina (advisor) ; Pour, Milan (referee)
RESUME Neisseria meningitidis, je lidský patogen způsobující život ohrožující onemocnění. Tato onemocnění jsou velice závažná a mohou být smrtelná již za několika hodin po manifestaci prvních příznaků. Proto je nezbytně nutná rychlá diagnóza a okamžité nasazení antibiotik. Avšak díky zvýšenému výskytu rezistentních bakteriálních kmenů se stává léčba i prevence velmi obtížná, a jsou tedy hledány nové způsoby terapie. Jedním z nových přístupů může být antiadhesivní terapie využívající glykanů, které zabraňují adhesi bakterií na hostitelské tkáně. Oligosacharidy a glykokonjugáty izolované z kravského a mateřského mléka prokázaly antiadhesivní účinky proti mnoho patogenům, stejně tak i proti N. meningitidis. Tyto komponenty by mohly být tedy využity jako bioaktivní přísada do potravin, a snižovat tak incidenci bakterielních onemocnění. Toto využití je však velmi ekonomicky náročné, a jsou tedy hledány jiné zdroje, které by mohly snížit náklady. Takový zdroj představuje syrovátka vznikající jako odpadní produkt při výrobě sýrů. Cílem této práce tedy bylo izolovat oligosacharidy z kravské syrovátky, separovat je na neutrální a acidické a otestovat jejich antiadhesivní účinky. Pro separaci izolovaných oligosacharidů bylo užito gelové a iontově výměnné chromatografie. Schopnost oligosacharidů zabránit adhesi N....
|
|
| |
|
| |
|
| |
|
|
Synthesis and Utilization of Selected Nitrogen Heterocycles
Mikušek, Jiří ; Pour, Milan (advisor) ; Veselý, Jan (referee) ; Bureš, Filip (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Inorganic and Organic Chemistry Candidate: Mgr. Jiří Mikušek Supervisor: prof. RNDr. Milan Pour, PhD. Title of Doctoral Thesis: Synthesis and Utilization of Selected Nitrogen Heterocycles The thesis is divided into two parts, both dealing with the synthesis of pyridine and pyrimidine derivatives. The first one is focused on the cyclization of enynes with gold(I) catalysts. Main attention is paid to the synthesis of various acyclic precursors starting from propargylamines, their addition to propiolates and Sonogashira cross-coupling. The mechanism of the cyclization with (TFP)AuCl is then discussed in detail. Prepared dihydropyridines were converted to pyridines or tetrahydropyridines. A precursor of the antidepressant drug paroxetine was prepared. The second part deals with quinazoline alkaloids with pyrimidine moiety and their structural variations towards potential organocatalysts and biologically active compounds. Therein new types of organocatalysts based on the structure of vasicine were prepared and screened on model aldolization and addition reactions. Prepared compounds were tested for bronchodilator activity.
|
|
|
Synthesis of Specifically Substituted Heterocycles via Catalytic Reactions
Kratochvíl, Jiří ; Pour, Milan (advisor) ; Kotora, Martin (referee) ; Dvořák, Dalimil (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Inorganic and Organic Chemistry Candidate Mgr. Jiří Kratochvíl Supervisor prof. RNDr. Milan Pour, Ph.D. Title of Doctoral Thesis Synthesis of Specifically Substituted Heterocycles via Catalytic Reactions This Ph.D. thesis deals with the synthesis of γ-alkylidene-α,β-unsaturated δ-lactones and lactams. Migita- Stille cross-coupling served as the key step in their preparation. Catalysis with palladium black was applied to the synthesis of the lactones and we demonstrated that it doesn't act as heterogeneous catalyst. Instead, it's only a precursor for catalytically active species, which is generated in situ and its true nature is unknown. The palladium nanoparticles are most likely responsible for the catalysis, although involvement of complexed atomic palladium cannot be excluded. Palladium black catalysis was also successfully applied to the synthesis of a series of structurally different substrates, which demonstrates its versatility and it was also proved that the catalyst can be easily recycled by simple filtration. An unusual Tsuji-Trost reaction then enabled transfer of the alkylidene substituent of the lactones to C5 furnishing polysubstituted heterocycles.
|
guest ::
RSS feed.