- DNA damage by ptaquiloside, a potent bracken carcinogen: Detection of selective strand breaks and identification of DNA cleavage products
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Ptaquiloside (1) is a potent carcinogen isolated from bracken fern. Under weakly alkaline conditions, the carcinogen is converted into dienone 2 which is thought to be the ultimate agent responsible for bracken fern carcinogenicity. This study details the selective alkylation and strand scission of DNA with dienone 2. Dienone 2 forms covalent adducts through N-3 of adenine or N-7 of guanine with opening of the cyclopropyl ring. Under physiological conditions, spontaneous cleavage of the N-glycosidic linkage occurs primarily at the modified adenines to produce abasic sites. The abasic sites are so unstable that subsequent backbone breakage occurs via a β-elimination reaction. Product analyses on sequencing gels and HPLC reveal evolution of the structures of the 5'- and 3'-termini that result from the abasic sites. In addition, the sequence selectivity for the DNA cleavage is demonstrated. The cleavage rates at the target adenine residues are affected by both 5'- and 3'-flanking nucleotides. The rank orders are 5'-AT > 5'-AG > 5'-AC > 5'-AA for 3'-flanking nucleotides and 5'AA > 5'-TA > 5'-GA > 5'-CA for 5'-flanking nucleotides (where A is a site of cleavage). The most favorable sequence is estimated to be 5'-AAAT. The present results on dienone 2 have also been compared with those of CC-1065 containing a similar reactive cyclopropyl ring.
- Kushida, Tatsushi,Uesugi, Motonari,Sugiura, Yukio,Kigoshi, Hideo,Tanaka, Hideyuki,Hirokawa, Junichi,Ojika, Makoto,Yamada, Kiyoyuki
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- SOLID PHASE SYNTHESIS OF CYCLIC OLIGODEOXYRIBONUCLEOTIDES.
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The polymer supported synthesis of cyclic oligomers of deoxycytidilic acid is described, by a method based on an oligonucleotide-solid phase linkage through the amino group of the base.
- Barbato, Stefania,Napoli, Lorenzo De,Mayol, Luciano,Piccialli, Gennaro,Santacroce, Ciro
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- Resistance towards exonucleases of dinucleotides with stereochemically altered internucleotide phosphate bonds
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Kinetic constants for the hydrolytic susceptibility of the internucleotide phosphate bond in normal dinucleotides [e.g., 2′-deoxycytidylyl- (3′>5′)-2′-deoxyuridine (dCpdU) and 2′-deoxyadenylyl- (3′→5′)-2′-deoxycytidine (dApdC)] and isomeric dinucleotides
- Nair, Vasu,Pal, Suresh
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- Mechanism of activation of β-D-2′-Deoxy-2′-fluoro- 2′-C-methylcytidine and inhibition of hepatitis C virus NS5B RNA polymerase
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β-D-2′-Deoxy-2′-fluoro-2′-C-methylcytidine (PSI-6130) is a potent specific inhibitor of hepatitis C virus (HCV) RNA synthesis in Huh-7 replicon cells. To inhibit the HCV NS5B RNA polymerase, PSI-6130 must be phosphorylated to the 5′-triphosphate form. The phosphorylation of PSI-6130 and inhibition of HCV NS5B were investigated. The phosphorylation of PSI-6130 by recombinant human 2′-deoxycytidine kinase (dCK) and uridine-cytidine kinase 1 (UCK-1) was measured by using a coupled spectrophotometric reaction. PSI-6130 was shown to be a substrate for purified dCK, with a Km of 81 μM and a kcat of 0.007 s -1, but was not a substrate for UCK-1. PSI-6130 monophosphate (PSI-6130-MP) was efficiently phosphorylated to the diphosphate and subsequently to the triphosphate by recombinant human UMP-CMP kinase and nucleoside diphosphate kinase, respectively. The inhibition of wild-type and mutated (S282T) HCV NS5B RNA polymerases was studied. The steady-state inhibition constant (Ki) for PSI-6130 triphosphate (PSI-6130-TP) with the wild-type enzyme was 4.3 μM. Similar results were obtained with 2′-C-methyladenosine triphosphate (Ki = 1.5 μM) and 2′-C-methylcytidine triphosphate (Ki = 1.6 μM). NS5B with the S282T mutation, which is known to confer resistance to 2′-C- methyladenosine, was inhibited by PSI-6130-TP as efficiently as the wild type. Incorporation of PSI-6130-MP into RNA catalyzed by purified NS5B RNA polymerase resulted in chain termination. Copyright
- Murakami, Eisuke,Bao, Haiying,Ramesh, Mangala,McBrayer, Tamara R.,Whitaker, Tony,Steuer, Holly M. Micolochick,Schinazi, Raymond F.,Stuyver, Lieven J.,Obikhod, Aleksandr,Otto, Michael J.,Furman, Phillip A.
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- Phosphorylation of isocarbostyril- and difluorophenyl-nucleoside thymidine mimics by the human deoxynucleoside kinases
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The thymidine mimics isocarbostyril nucleosides and difluorophenyl nucleosides were tested as deoxynucleoside kinase substrates using recombinant human cytosolic thymidine kinase (TK1) and deoxycytidine kinase (dCK), and mitochondrial thymidine kinase (TK2) and deoxyguanosine kinase (dGK). The isocarbostyril nucleoside compound 1-(2-deoxy-β-D-ribofuranosyl)- isocarbostyril (EN1) was a poor substrate with all the enzymes. The phosphorylation rates of EN1 with TK1 and TK2 were cat/Km) with both TK1 and dGK, but not with TK2. The kcat/Km value for EN2 with TK2 was 12.6% relative to that for Thd. Of the difluorophenyl nucleosides, 5-(1′-(2′-deoxy-β-D-ribofuranosyl))-2,4-difluorotoluene (JW1) and 1-(1′-(2′-deoxy-β-D-ribofuranosyl))-2,4-difluoro-5- iodobenzene (JW2) were substrates for TK1 with phosphorylation efficiencies of about 5% relative to that for Thd. Both analogues were considerably more efficient substrates for TK2, with kcat/Km values of 45% relative to that for Thd. 2,5-Difluoro-4-[1-(2-deoxy-β-L-ribofuranosyl)]- aniline (JW5), a L-nucleoside mimic, was phosphorylated up to 15% as efficiently as deoxycytidine by dCK. These data provide a possible explanation for the previously reported lack of cytotoxicity of the isocarbostyril- and difluorophenyl nucleosides, but potential mitochondrial effects of EN2, JW1 and JW2 should be further investigated.
- Al-Madhoun, Ashraf Said,Eriksson, Staffan,Wang, Zhi-Xian,Naimi, Ebrahim,Knaus, Edward E.,Wiebe, Leonard I.
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- Differences in kinetic properties of pure recombinant human and mouse deoxycytidine kinase
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Human and mouse deoxycytidine kinase (dCK) (EC 2.7.1.74) were cloned and expressed in Escherichia coli. Michaelis-Menten kinetics were determined for the purified enzymes with 2'-deoxycytidine (dCyd), 2'-deoxyadenosine (dAdo), 2-chloro-2'-deoxyadenosine (CdA), 2',3'dideoxycytidine (ddCyd) and 9-β-D-arabinofuranosylguanine (araG) as substrates and ATP and UTP as phosphate donors. Both human and mouse dCK showed highest affinity to dCvd with K(m) values of 0.05-0.2 μM. The anti-leukaemic compound CdA was the superior substrate of the nucleoside analogues tested. Both enzymes were able to efficiently utilize ATP and UTP as phosphate donors. However, the use of UTP instead of ATP as phosphate donor decreased K(m) values for all substrates investigated. The kinetic properties of mouse and human dCK differed in that the human enzyme showed higher affinity for the substrates dAdo, CdA, ddCyd and araG. The human enzyme also showed higher affinity for ATP and UTP. The ability to phosphorylate dCyd was, however, similar for both human and mouse dCK. At physiological concentration of the feedback inhibitor dCTP, mouse dCK showed lower activity than human dCK for all substrates investigated.
- Johansson, Magnus,Karlsson, Anna
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- Immobilized Drosophila melanogaster deoxyribonucleoside kinase (DmdNK) as a high performing biocatalyst for the synthesis of purine arabinonucleotides
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Fruit fly (Drosophila melanogaster) deoxyribonucleoside kinase (DmdNK; EC: 2.7.1.145) was characterized for its substrate specificity towards natural and non-natural nucleosides, confirming its potential in the enzymatic synthesis of modified nucleotides. DmdNK was adsorbed on a solid ion exchange support (bearing primary amino groups) achieving an expressed activity >98%. Upon cross-linking with aldehyde dextran, expressed activity was 30-40%. Both biocatalysts (adsorbed or cross-linked) were stable at pH 10 and room temperature for 24 h (about 70% of retained activity). The cross-linked DmdNK preparation was used for the preparative synthesis of arabinosyladenine monophosphate (araA-MP) and fludarabine monophosphate (FaraAMP). Upon optimization of the reaction conditions (50 mM ammonium acetate, substrate/ATP ratio= 1:1.25, 2 mM MgCl2, 378C, pH 8) immobilized DmdNK afforded the title nucleotides with high conversion (>90%), whereas with the soluble enzyme lower conversions were achieved (78-87%). Arabinosyladenine monophosphate was isolated in 95% yield and high purity (96.5%).
- Serra, Immacolata,Conti, Silvia,Piskur, Jure,Clausen, Anders R.,Munch-Petersen, Birgitte,Terreni, Marco,Ubiali, Daniela
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- Evaluation of the role of three candidate human kinases in the conversion of the hepatitis C virus inhibitor 2′-C-methyl-cytidine to its 5′-monophosphate metabolite
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Nucleoside analogs are effective inhibitors of the hepatitis C virus (HCV) in the clinical setting. One such molecule, 2′-C-methyl-cytidine (2′-MeC), entered clinical development as NM283, a valine ester prodrug form of 2′-MeC possessing improved oral bioavailability. To be active against HCV, 2′-MeC must be converted to 2′-MeC triphosphate which inhibits NS5B, the HCV RNA-dependent RNA polymerase. Conversion of 2′-MeC to 2′-MeC monophosphate is the first step in 2′-MeC triphosphate production and is thought to be the rate-limiting step. Here we investigate which of three possible enzymes, deoxycytidine kinase (dCK), uridine-cytidine kinase 1 (UCK1), or uridine-cytidine kinase 2 (UCK2), mediate this first phosphorylation step. Purified recombinant enzymes UCK2 and dCK, but not UCK1, could phosphorylate 2′-MeC in vitro. However, siRNA knockdown experiments in three human cell lines (HeLa, Huh7 and HepG2) defined UCK2 and not dCK as the key kinase for the formation of 2′-MeC monophosphate in cultured human cells. These results underscore the importance of confirming enzymatic kinase data with appropriate cell-based assays. Finally, we present data suggesting that inefficient phosphorylation by UCK2 likely limits the antiviral activity of 2′-MeC against HCV. This paves the way for the use of a nucleotide prodrug approach to overcome this limitation.
- Golitsina, Nina L.,Danehy Jr., Francis T.,Fellows, Ross,Cretton-Scott, Erika,Standring, David N.
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- Cell- And Polymerase-Selective Metabolic Labeling of Cellular RNA with 2′-Azidocytidine
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Metabolic labeling of cellular RNA is a powerful approach to investigate RNA biology. In addition to revealing whole transcriptome dynamics, targeted labeling strategies can be used to study individual RNA subpopulations within complex systems. Here, we describe a strategy for cell- and polymerase-selective RNA labeling with 2′-azidocytidine (2′-AzCyd), a modified nucleoside amenable to bioorthogonal labeling with SPAAC chemistry. In contrast to 2′-OH-containing pyrimidine ribonucleosides, which rely upon uridine-cytidine kinase 2 (UCK2) for activation, 2′-AzCyd is phosphorylated by deoxycytidine kinase (dCK), and we find that expression of dCK mediates cell-selective 2′-AzCyd labeling. Further, 2′-AzCyd is primarily incorporated into rRNA and displays low cytotoxicity and high labeling efficiency. We apply our system to analyze the turnover of rRNA during ribophagy induced by oxidative stress or mTOR inhibition to show that 28S and 18S rRNAs undergo accelerated degradation. Taken together, our work provides a general approach for studying dynamic RNA behavior with cell and polymerase specificity and reveals fundamental insights into nucleotide and nucleic acid metabolism.
- Wang, Danyang,Zhang, Yu,Kleiner, Ralph E.
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- Electron transfer in di(deoxy)nucleoside phosphates in aqueous solution: Rapid migration of oxidative damage (via adenine) to guanine
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In aqueous solution, the one-electron loss centers created statistically by the oxidant SO4.- or by photoionization in di(2′-deoxy)nucleoside phosphates (DNPs) containing the base guanine (G) become localized at G, as concluded from pulse radiolysis and 193-nm laser photolysis experiments. From the latter it is evident that, in the case of adenylyl(3′→5′)guanosine (ApG), the charge-transfer process is complete in ≤50 ns. With DNPs containing a pyrimidine and the purine base adenine, the oxidative damage is collected by the adenine moiety (k ≥ 2 × 105 s-1).
- Candeias, Luis Pedro,Steenken, Steen
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- Fully automated continuous meso-flow synthesis of 5′-nucleotides and deoxynucleotides
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The first continuous meso-flow synthesis of natural and non-natural 5′-nucleotides and deoxynucleotides is described, representing a significant advance over the corresponding in-flask method. By means of this meso-flow technique, a synthesis with time consumption and high-energy consumption becomes facile to generate products with great efficiency. An abbreviated duration, satisfactory output, and mild reaction conditions are expected to be realized under the present procedure.
- Zhu, Chenjie,Tang, Chenglun,Cao, Zhi,He, Wei,Chen, Yong,Chen, Xiaochun,Guo, Kai,Ying, Hanjie
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p. 1575 - 1581
(2015/02/19)
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- Two thymidine kinases and one multisubstrate deoxyribonucleoside kinase salvage DNA precursors in Arabidopsis thaliana
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Deoxyribonucleotides are the building blocks of DNA and can be synthesized via de novo and salvage pathways. Deoxyribonucleoside kinases (EC 2.7.1.145) salvage deoxyribonucleosides by transfer of a phosphate group to the 5' of a deoxyribonucleoside. This salvage pathway is well characterized in mammals, but in contrast, little is known about how plants salvage deoxyribonucleosides. We show that during salvage, deoxyribonucleosides can be phosphorylated by extracts of Arabidopsis thaliana into corresponding monophosphate compounds with an unexpected preference for purines over pyrimidines. Deoxyribonucleoside kinase activities were present in all tissues during all growth stages. In the A. thaliana genome, we identified two types of genes that could encode enzymes which are involved in the salvage of deoxyribonucleosides. Thymidine kinase activity was encoded by two thymidine kinase 1 (EC 2.7.1.21)-like genes (AtTK1a and AtTK1b). Deoxyadenosine, deoxyguanosine and deoxycytidine kinase activities were encoded by a single AtdNK gene. T-DNA insertion lines of AtTK1a and AtTK1b mutant genes had normal growth, although AtTK1a AtTK1b double mutants died at an early stage, which indicates that AtTK1a and AtTK1b catalyze redundant reactions. The results obtained in the present study suggest a crucial role for the salvage of thymidine during early plant development. 2012 The Authors Journal compilation
- Clausen, Anders R.,Girandon, Lenart,Ali, Ashfaq,Knecht, Wolfgang,Rozpedowska, Elzbieta,Sandrini, Michael P. B.,Andreasson, Erik,Munch-Petersen, Birgitte,Piskur, Jure
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p. 3889 - 3897
(2013/01/13)
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- A single nuclease-resistant linkage in DNA as a versatile tool for the characterization of DNA lesions: Application to the guanine oxidative lesion g+34 generated by metalloporphyrin/KHSO5 reagent
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The oxidation of an oligonucleotide containing a single nuclease-resistant phosphodiester link, a stereoisomerically pure methylphosphonate, by manganese (Mn-TMPyP) or iron (Fe-TMPyP) porphyrin associated to KHSO5 allowed the isolation and characterization of a guanine lesion corresponding to an increase of mass of 34 amu as compared to guanine ( G+34 ), namely, 5-carboxamido-5-formamido-2-iminohydantoin. Enzymatic digestion of the damaged oligonucleotide afforded, apart from the undamaged nucleotide monomer pool, a unique dinucleotide doubly modified with a methylphosphonate and an oxidized guanine base that is suitable for NMR analysis. The method can be applied to the study of any DNA lesion. More importantly, the method can be extended to the analysis of DNA damage in a sequence context. Any preselected residue in a DNA sequence may be individually analyzed by the easy introduction of a single nuclease-resistant link at the 3′- or 5′-position.
- Tomaszewska, Agnieszka,Mourgues, Sophie,Guga, Piotr,Nawrot, Barbara,Pratviel, Genevieve
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p. 2505 - 2512
(2013/01/15)
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- Mechanism of the alkali degradation of (6-4) photoproduct-containing DNA
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The (6-4) photoproduct is one of the major damaged bases produced by ultraviolet light in DNA. This lesion is known to be alkali-labile, and strand breaks occur at its sites when UV-irradiated DNA is treated with hot alkali. We have analyzed the product obtained by the alkali treatment of a dinucleoside monophosphate containing the (6-4) photoproduct, by HPLC, NMR spectroscopy, and mass spectrometry. We previously found that the N3-C4 bond of the 5′ component was hydrolyzed by a mild alkali treatment, and the present study revealed that the following reaction was the hydrolysis of the glycosidic bond at the 3′ component. The sugar moiety of this component was lost, even when a 3′-flanking nucleotide was not present. Glycosidic bond hydrolysis was also observed for a dimer and a trimer containing 5-methyl-2-pyrimidinone, which was used as an analog of the 3′ component of the (6-4) photoproduct, and its mechanism was elucidated. Finally, the alkali treatment of a tetramer, d(GT(6-4)TC), yielded 2′-deoxycytidine 5′-monophosphate, while 2′-deoxyguanosine 3′-monophosphate was not detected. This result demonstrated the hydrolysis of the glycosidic bond at the 3′ component of the (6-4) photoproduct and the subsequent strand break by β-elimination. It was also shown that the glycosidic bond at the 3′ component of the Dewar valence isomer was more alkali-labile than that of the (6-4) photoproduct. The Royal Society of Chemistry 2012.
- Arichi, Norihito,Inase, Aki,Eto, Sachise,Mizukoshi, Toshimi,Yamamoto, Junpei,Iwai, Shigenori
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p. 2318 - 2325
(2012/04/10)
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- An efficient reagent for the phosphorylation of deoxyribonucleosides, DNA oligonucleotides, and their thermolytic analogues
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(Chemical Equation Presented) The phosphoramidite 11 was prepared in three steps from methyl 2-mercaptoacetate and demonstrated efficiency in the synthesis of conventional 5′-/3′-phosphate/thiophosphate monoester derivatives of 2′-deoxyribonucleosides and DNA oligonucleotides. Moreover, the use of 11 has enabled the preparation of the dinucleoside phosphorothioate analogue 26 in high yields (>95%) with minimal cleavage (2%) of the thermolytic thiophosphate protecting group.
- Ausin, Cristina,Grajkowski, Andrzej,Cieslak, Jacek,Beaucage, Serge L.
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p. 4201 - 4204
(2007/10/03)
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- Unnatural enantiomers of 5-azacytidine analogues: Syntheses and enzymatic properties
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Although 2'-deoxy-β-D-5-azacytidine (Decitabine) and β-D-5-azacytidine display potent antileukemic properties, their therapeutic use is hampered by their sensitivity to nucleophiles and to deamination catalysed by cytidine deaminase. As shown earlier [Shafiee M., Griffon J.-F., Gosselin G., Cambi A., Vincenzetti S., Vita A., Erikson S., Imbach J.-L., Maury G., Biochem. Pharmacol. 56 (1998) 1237-1242], β-L-enantiomers of cytidine derivatives are resistant to cytidine deaminase. We thus synthesized several 5-azacytosine β-L-nucleoside analogues to evaluate their enzymatic and biological properties. 2'-Deoxy-β-L-5-azacytidine (L-Decitabine), β-L-5-azacytidine, 1-(β-L-xylo-furanosyl)5-azacytosine, and 1-(2-deoxy-β-L-threo-pentofuranosyl)5-azacytosine were stereospecifically prepared starting from L-ribose and L-xylose. D- and L-enantiomers of 2'-deoxy-β-5-azacytidine were weak substrates of human recombinant deoxycytidine kinase (dCK) compared to β-D-deoxycytidine, whereas both enantiomers of β-5-azacytidine or the L-xylo-analogues were not substrates of the enzyme. As expected, none of the presently reported derivatives of β-L-5-azacytidine was a substrate of human recombinant cytidine deaminase (CDA). The prepared compounds were tested for their activity against HIV and HBV and they did not show any significant activity or cytotoxicity. In the case of L-Decitabine, this suggests that the enantioselectivities of concerned enzymes other than dCK and CDA might not be favourable. (C) 2000 Editions scientifiques et medicales Elsevier SAS.
- Gaubert, Gilles,Mathe, Christophe,Imbach, Jean-Louis,Eriksson, Staffan,Vincenzetti, Silvia,Salvatori, Daniela,Vita, Alberto,Maury, Georges
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p. 1011 - 1019
(2007/10/03)
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- A new method for the phosphorylation of nucleosides
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A new phosphorylating reagent, 2-O-(4,4'-dimethoxytrityl)ethylsulfonylethan-2'-yl-phosphate (1), was developed for the phosphorylation of primary and secondary alcohols of nucleosides. In the many examples studied, yields in the phosphorylation step were excellent (~80 to 95%). There is potential for wide applicability of this procedure, not only in nucleoside and nucleotide chemistry, but also in the phosphorylation of biomolecules such as carbohydrates and amino acids. (C) 2000 Elsevier Science Ltd.
- Taktakishvili,Nair
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p. 7173 - 7176
(2007/10/03)
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- Recognition and inhibition of HIV integrase by novel dinucleotides
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HIV integrase is involved in the integration of viral DNA into chromosomal DNA, a biological process that occurs by a sequence involving HIV DNA splicing and subsequent integration steps. In the quest for small nucleotide systems with nuclease stability of the internucleotide phosphate bond and critical structural features for recognition and inhibition of HIV-1 integrase, we have discovered novel, nuclease-resistant dinucleotides with defined base sequences that are inhibitors of this key viral enzyme. Synthetic methodologies utilized for the syntheses of the novel dinucleotides include an excellent new phosphorylating agent.
- Taktakishvili, Michael,Neamati, Nouri,Pommier, Yves,Pal, Suresh,Nair, Vasu
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p. 5671 - 5677
(2007/10/03)
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- Additional Evidence for the Exceptional Mechanism of the Acid-catalysed Hydrolysis of 4-Oxopyrimidine Nucleosides: Hydrolysis of 1-(1-Alkoxyalkyl)uracils, Seconucleosides, 3'-C-Alkyl Nucleosides and Nucleoside 3',5'-Cyclic Monophosphates
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The rate constants for the acid-catalysed hydrolysis of 1-(1-alkoxyethyl)uracils and 1-alkoxymethyluracils have been determined.With both series of compounds, the hydrolysis rate is rather insensitive to the polar nature of the alkoxy group, in striking contrast with the hydrolysis of the corresponding analogues of adenine and cytosine nucleosides, which react via rate-limiting formation of an oxocarbenium ion intermediate.Furthermore, it has been shown that 3',5'-cyclic monophosphates of thymidine and uridine undergo hydrolysis of the N-glycosidic bond 760 and 260 times as fast as their parent nucleosides, while the cyclic monophosphates of 2'-deoxyadenosine and adenosine are depurinated much more slowly than the corresponding nucleosides.On this basis it is suggested that 4-oxopyrimidine nucleosides are hydrolysed by opening of the sugar ring.To obtain further evidence for this exceptional mechanism, comparative kinetic measurements with some seco- and 3'-C-alkyl nucleosides of uracil and adenine have been carried out.
- Oivanen, Mikko,Rajamaeki, Markku,Varila, Jaana,Hovinen, Jari,Mikhailov, Sergey,Loennberg, Harri
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p. 309 - 314
(2007/10/02)
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- Covalent alkylation of DNA with duocarmycin A. Identification of abasic site structure
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Alkylation of d(CGTATACG) by antitumor antibiotic duocarmycin A was investigated. It was found that N3 of adenine6 (A6) attacks the cyclopropane subunit of duocarmycin A to produce covalently alkylated adduct 5. Upon heating (90 °C, 5 min) the adduct 5 decomposed to modified oligomer 1 with concomitant release of adenine adduct 2.
- Sugiyama,Hosoda,Saito,Asai,Saito
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p. 7197 - 7200
(2007/10/02)
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- Chemical Synthesis of 5'-Phosphorylated DNA Fragments and Their Constituents
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Phosphoryl tris-triazole has been applied to the synthesis of DNA fragments and their constituents bearing 5'-phosphomonoester function and to the preparation of deoxynucleoside 5'- or 3'-diphosphates.
- Jankowska, Jadwiga,Stawinski, Jacek
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