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Direct enzymatic synthesis of aldehyde-functionalized DNA and its conjugation with hydrazines and amines
Raindlová, Veronika ; Hocek, Michal
A new simple methodology for DNA conjugation or staining was developed. 2′-Deoxyribonucleoside triphosphates (dNTPs) bearing reactive aldehyde group were prepared by one-step Suzuki cross-coupling reaction of halogenated dNTPs with boronic acid. These modified dNTPs were enzymatically incorporated into DNA by primer extension (PEX) or amplified by polymerase chain reaction (PCR) using different DNA polymerases. The followup reaction between aldehyde-modified PCR products and hydrazine derivatives gave coloured DNA conjugated hydrazones. This methodology was also used for further conjugations of aldehyde-modified 2′-deoxyribonucleoside monophosphates (dNMPs) with amines by reductive amination.
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Dichotomy in regioselectivity of Pd-catalyzed direct C-H arylation of protected uracils
Čerňová, Miroslava ; Hocek, Michal
Uracil bases and nucleosides bearing aryl groups in positions 5 or 6 are an important class of compounds and display wide range of biological activities1. In addition, arylation in position 5 is often used for labeling of nucleotides, oligonucleotides and DNA for applications in bioanalysis or chemical biology2. The 5- or 6-aryluracils can be prepared by heterocyclization or by cross-coupling reactions of halouracils with arylboronic acids or stannanes or metallated uracils with aryl halides. Direct C–H arylation of uracil is an alternative to classical cross-couplings where the preparation of reactive organometallic reagent is avoided. Recently, we have developed regioselective Pd-catalyzed and/or Cu-mediated direct C–H arylations of 1,3-dimethyluracil as a model compound for pyrimidine bases to position C-5 or C-6 3.
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Modular synthesis of 5-substituted thiophene and furan C-nucleosides and their analogues
Bárta, Jan ; Hocek, Michal
A new modular and efficient methodology for the preparation of 5-substituted thiophen-2-yl and 5-substituted furan-2-yl C-nucleosides was developed. A Friedel–Crafts-type of C-glycosidation of 2-bromothiophene or 2-bromofuran with bis-toluoyl protected methyl- 2′-deoxyribofuranoside in presence of Lewis acid gave the desired bis-toluoyl protected 5-bromothiophne and 5-bromofuran C-nucleosides in good yields. They were used as key intermediates for Stille or Suzuki coupling whith (hetero)arylstannanes or boronic acids to afford a series of 5-(hetero)aryl thiophene and 5-(heteroaryl)furan C-nucleosides.
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Hetaryl derivatives of 7-deazapurine ribonucleosides: potent cytostatic agents
Perlíková, Pavla ; Nauš, Petr ; Bourderioux, Aurelie ; Hocek, Michal
A series of novel 7-deazapurine ribonucleosides substituted with aryl and hetaryl groups has been prepared. Suzuki or Stille cross-coupling reactions with 6-chloro-7-deazapurine ribonucleosides substituted with H, F of Cl atom in position 7 were used in the key step of the synthesis. Either cross-coupling of protected ribonucleoside with appropriate (het)arylboronic acid or stannane followed by deprotection, or single-step aqueous-phase Suzuki cross-coupling reaction of unprotected 7-deazapurine ribonucleoside with boronic acid provided target (het)aryl-7-deazapurine ribonucleosides. 6-Furyl- and 6-thienyl-7-deazapurine ribonucleosides showed cytostatic effect in multiple cancer cell lines in nanomolar range. Application of cyclosaligenyl and alanyl-ester phosphoramidate prodrugs did not improved cytostatic activity of parent nucleosides.
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Development of a general and modular approach to C-nucleosides
Kubelka, Tomáš ; Štefko, Martin ; Bárta, Jan ; Joubert, Nicolas ; Urban, Milan ; Chapuis, Hubert Jean ; Hocek, Michal
Highly efficient and modular approach was developed for the synthesis of various types of new (het)aryl C-nucleosides. This protocol consists of the synthesis of haloaryl-C-nucleoside intermediates, followed by a functional group transformation to introduce various substituents. Using this approach protected 2′-deoxy-C-nucleosides bearing halogenated benzene, pyridine, thiophene, furane and pyrimidine were prepared. These intermediates were then submitted to a wide range of palladium-catalyzed reactions. The same approach was also used for preparation of C-nucleosides bearing ribofuranose moiety. Functional ribofuranosides bearing diverse substituted pyridine and benzene nucleobases were prepared in this way.
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