- Cell-penetrating and neurotargeting dendritic siRNA nanostructures
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We report the development of dendritic siRNA nanostructures that are able to penetrate even difficult to transfect cells such as neurons with the help of a special receptor ligand. The nanoparticles elicit strong siRNA responses, despite the dendritic str
- Brunner, Korbinian,Harder, Johannes,Halbach, Tobias,Willibald, Julian,Spada, Fabio,Gnerlich, Felix,Sparrer, Konstantin,Beil, Andreas,M?ckl, Leonhard,Br?uchle, Christoph,Conzelmann, Karl-Klaus,Carell, Thomas
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Read Online
- Intragenomic Decarboxylation of 5-Carboxy-2′-deoxycytidine
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Cellular DNA is composed of four canonical nucleosides (dA, dC, dG and T), which form two Watson–Crick base pairs. In addition, 5-methylcytosine (mdC) may be present. The methylation of dC to mdC is known to regulate transcriptional activity. Next to these five nucleosides, the genome, particularly of stem cells, contains three additional dC derivatives, which are formed by stepwise oxidation of the methyl group of mdC with the help of Tet enzymes. These are 5-hydroxymethyl-dC (hmdC), 5-formyl-dC (fdC), and 5-carboxy-dC (cadC). It is believed that fdC and cadC are converted back into dC, which establishes an epigenetic control cycle that starts with methylation of dC to mdC, followed by oxidation and removal of fdC and cadC. While fdC was shown to undergo intragenomic deformylation to give dC directly, a similar decarboxylation of cadC was postulated but not yet observed on the genomic level. By using metabolic labelling, we show here that cadC decarboxylates in several cell types, which confirms that both fdC and cadC are nucleosides that are directly converted back to dC within the genome by C?C bond cleavage.
- Carell, Thomas,Kamińska, Ewelina,Korytiaková, Eva,Müller, Markus,Reichl, Andreas
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Read Online
- Synthesis method of 2 ’ -fluoro -2 ’ - deoxyuridine and intermediate thereof
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The synthesis method of 2 ’ -fluoro -2 ’ - deoxyuridine is novel in synthetic route, simple and convenient to operate, high in yield, good in safety, free of column chromatography and suitable for industrial production. Among them R is a hydroxyl protecting group, most preferably a tetrahydropyranyl group (THP group) as a hydroxyl protecting group. R is a conventional protecting group for the hydroxyl group in the art, and R THP
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Paragraph 0090-0092
(2021/11/26)
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- NUCLEIC ACID CHEMICAL MODIFICATIONS
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he present invention provides nucleosides of formula (1) and oligonucleotides comprising at least on nucleoside of formula (2): Another aspect of the invention relates to a method of inhibiting the expression of a gene in cell, the method comprising (a) c
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Page/Page column 242-243
(2010/09/18)
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- NON-NATURAL RIBONUCLEOTIDES, AND METHODS OF USE THEREOF
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One aspect of the present invention relates to modified nucleosides and oligonucleotides comprising such modified nucleosides. Another aspect of the invention relates to a method of inhibiting the expression of a gene in call, the method comprising (a) co
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Page/Page column 151-152
(2009/10/22)
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- Growth inhibition of Mycobacterium bovis, Mycobacterium tuberculosis and Mycobacterium avium in vitro: Effect of 1-β-D-2′-arabinofuranosyl and 1-(2′-deoxy-2′-fluoro-β-D-2′-ribofuranosyl) pyrimidine nucleoside analogs
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The resurgence of tuberculosis and the emergence of multiple-drug-resistant strains of Mycobacteria necessitate the search for new classes of antimycobacterial agents. We synthesized a series of 1-β-D-2′- arabinofuranosyl and 1-(2′-deoxy-2′-fluoro-β-D-rib
- Johar, Monika,Manning, Tracey,Tse, Christopher,Desroches, Nancy,Agrawal,Kunimoto, Dennis Y.,Kumar, Rakesh
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p. 3696 - 3705
(2008/02/09)
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- PROCESS FOR PRODUCING 2 -DEOXY-2 -FLUOROURIDINE
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1-β-D-Arabinofuranosyluracil in 3',5'-hydroxyl-protected form is reacted with a trifluoromethanesulfonylating agent in the presence of an organic base to convert it into a 2'-triflate form, and then it is reacted with a fluorinating agent containing "a salt or complex formed by an organic base and hydrofluoric acid" to produce 2'-deoxy-2'-fluorouridine in 3',5'-hydroxyl-protected form. A deprotecting agent is further caused to act thereon to obtain 2'-deoxy-2'-fluorouridine. The 2'-deoxy-2'-fluorouridine obtained can efficiently be purified by temporarily converting it into a 3',5'-diacetyl form, recrystallizing the 3',5'-diacetyl form, and then deacetylating it. Thus, high-purity 2'-deoxy-2'-fluorouridine can be produced.
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Page/Page column 16; 22-23
(2008/06/13)
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- Synthesis and anti-viral activity of a series of D- and l-2′-deoxy-2′-fluororibonucleosides in the subgenomic HCV replicon system
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Based on the discovery of (2′R)-D-2′-deoxy-2′- fluorocytidine as a potent anti-hepatitis C virus (HCV) agent, a series of D- and L-2′-deoxy-2′-fluororibonucleosides with modifications at 5- and/or 4-positions were synthesized and evaluated for their in vitro activity against HCV and bovine viral diarrhea virus (BVDV). The key step in the synthesis, the introduction of 2′-fluoro group, was achieved by either fluorination of 2,2′-anhydronucleosides with hydrogen fluoride-pyridine or potassium fluoride, or a fluorination of arabinonucleosides with DAST. Among the 27 analogues synthesized, only the 5-fluoro compound, namely (2′R)-D-2′-deoxy-2′,5-difluorocytidine (13), demonstrated potent anti-HCV activity and toxicity to ribosomal RNA. The replacement of the 4-amino group with a thiol group resulted in the loss of activity, while the 4-methylthio substituted analogue (25) exhibited inhibition of ribosomal RNA. As N4-hydroxycytidine (NHC) had previously shown potent anti-HCV activity, we combined the two functionalities of the N4-hydroxyl and the 2′-fluoro into one molecule, resulting (2′R)-D-2′-deoxy- 2′-fluoro-N4-hydroxycytidine (23). However, this nucleoside showed neither anti-HCV activity nor toxicity. All the L-forms of the analogues were devoid of anti-HCV activity. None of the compounds showed anti-BVDV activity, suggesting that the BVDV system cannot always predict anti-HCV activity.
- Shi, Junxing,Du, Jinfa,Ma, Tianwei,Pankiewicz, Krzysztof W.,Patterson, Steven E.,Tharnish, Phillip M.,McBrayer, Tamara R.,Stuyver, Lieven J.,Otto, Michael J.,Chu, Chung K.,Schinazi, Raymond F.,Watanabe, Kyoichi A.
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p. 1641 - 1652
(2007/10/03)
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- Synthesis of a technetium-99m-labeled thymidine analog: A potential HSV1-TK substrate for non-invasive reporter gene expression imaging
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{2-[5-(2′-Fluoro-2′-deoxyuridin-5-yl)pent-4(E)-enyl] [2-(2-mercaptoethyl)aminoethyl]aminoethanethiolato(3)-N,N′,S,S′} oxo-[99mTc]technetium(V), a potential viral thymidine kinase substrate, was synthesized by coupling 2′-fluoro-2′-deoxyuridine
- Zhang, Yi,Dai, Xiaoman,Kallmes, David F.,Pan, Dongfeng
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p. 8673 - 8676
(2007/10/03)
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- Functionalized nucleoside 5'-triphosphates for in vitro selection of new catalytic ribonucleic acids
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A series of novel 2'-modified nucleoside 5'-triphosphates was synthesized. The amino, imidazole, and carboxylate functionalities were attached to the 5-position of pyrimidine base of these molecules through alkynyl and alkyl spacers, respectively. Two different phosphorylation methods were used to optimize the yields of these highly modified triphosphates. (C) 2000 Elsevier Science Ltd. All rights reserved.
- Matulic-Adamic, Jasenka,Daniher, Andrew T.,Karpeisky, Alexander,Haeberli, Peter,Sweedler, David,Beigelman, Leonid
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p. 1299 - 1302
(2007/10/03)
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- 132. Structural Comparison of Oligoribonucleotides and Their 2′-Deoxy-2′-fluoro Analogs by Heteronuclear NMR Spectroscopy
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1-(2′-Deoxy-2′-fluororibofuranosyl)pyrimidines were synthesized and incorporated into an RNA oligonucleotide to give 5′-r[CfGCf(UfUfC fG)GCfG]-3′ (Cf: short form of Cd2′f2′ = 2′-deoxy-2′-fluorocytidine; Uf: short form of Ud2′f2′ = 2′-deoxy-2′-fluorouridine). The oligomer was investigated by means of UV, CD, and NMR spectroscopy to address the question of how F-labels can substitute 13C-labels in the ribose ring. Through-space (NOE) and through-bond (scalar couplings) experiments were performed that make use of the ameliorated chemical-shift dispersion induced by 19F as an alternative heteronucleus. A comparison of the structures of fluorinated vs. unmodified oligomer is given. It turns out that the fluorinated oligonucleotide exists in a 14:3 equilibrium between a hairpin and a duplex conformation, in contrast to the unmodified oligonucleotide which predominantly adopts the hairpin conformation. Furthermore, the fluorinated hairpin structure adopts two distinct conformations that differ in the sugar conformation of the Uf5 and Cf6 nucleoside units, as detected by the 19F-NMR chemical shifts. The role of the 2′-OH group as stabilizing element in RNA secondary structure is discussed.
- Reif, Bernd,Wittmann, Valentin,Schwalbe, Harald,Griesinger, Christian,Woerner, Karlheinz,Jahn-Hofmann, Kerstin,Engels, Joachim W.,Bermel, Wolfgang
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p. 1952 - 1971
(2007/10/03)
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