118-00-3Relevant articles and documents
Simple method for fast deprotection of nucleosides by triethylamine- catalyzed methanolysis of acetates in aqueous medium
Meier, Lidiane,Monteiro, Gustavo C.,Baldissera, Rodrigo A.M.,Sa?, Marcus Mandolesi
, p. 859 - 866 (2010)
A straightforward methodology for deacetylation of protected ribonucleosides was developed based on triethylamine-catalyzed solvolysis in aqueous methanol. Reactions are completed in a few minutes under microwave irradiation and the free nucleosides are obtained in high yield after simple evaporation of volatiles. Other important features include the involvement of readily available reagents and the compatibility with diverse functional groups, which make this process very attractive for broad application.
Heterocyclic Synthesis via a 1,3-Dicyclohexylcarbodiimide-Mediated Cyclodesulfurative Annulation Reaction. New Methodology for the Preparation of Guanosine and Guanosine-Type Nucleoside Analogues
Groziak, Michael P.,Chern, Ji-Wang,Townsend, Leroy B.
, p. 1065 - 1069 (1986)
Treatment of 5-amino-1-β-D-ribofuranosylimidazole-4-carboxamide (1, AICA-ribonucleoside) with methoxycarbonyl isothiocyanate followed by cyclodesulfurization of the resulting methoxycarbonylated thioureido derivative with 1,3-dicyclohexylcarbodiimide (DCC) has furnished 5--1-β-D-ribofuranosylimidazole-4-carbonitrile (6), not 2--9-β-D-ribofuranosylpurin-6-one (4).Using 1 labeled with 18O in the carboxamide moiety, the conversion of 1 to 6 is shown to proceed with retention of the 18O label.This finding has suggested the presence of a oxazine intermediate in an intramolecular dehydration reaction mechanism.Under similar reaction conditions, methyl 5-amino-1-β-D-ribofuranosylimidazole-4-carboximidate (13) affords 6-methoxy-2--9-β-D-ribofuranosylpurine (14), which gives guanosine upon deprotection with iodotrimethylsilane.The use of this methoxycarbonyl isothiocyanate/DCC cyclodesulfurization method on heterocyclic o-amino carboximidate esters thus provides a highly efficient entry into the class of guanosine-type nucleoside analogues.
N,N-Dibenzyl formamidine as a new protective group for primary amines
Vincent, Stephane,Mons, Stephane,Lebeau, Luc,Mioskowski, Charles
, p. 7527 - 7530 (1997)
Primary amines can be converted in high yield into N,N-dibenzyl formamidines under mild conditions. The N,N-dibenzyl formamidine group was found to be effective as a protective group for primary amines as it is stable to a variety of conditions and can be removed by catalytic hydrogenation.
Phosphorylating reagent-free synthesis of 5′-phosphate oligonucleotides by controlled oxidative degradation of their 5′-end
Sallamand, Corinne,Miscioscia, Audrey,Lartia, Remy,Defrancq, Eric
, p. 2030 - 2033 (2012)
The 5′-phosphorylated oligonucleotides (5′-pONs) are currently synthesized using expensive and sensitive modified phosphoramidite reagents. In this work, a simple, cost-effective, efficient, and automatable method is presented, based on the controlled oxidation of the 5′-terminal alcohol followed by a β-elimination reaction. The latter reaction leads to the removal of the terminal 5′-nucleoside and subsequent formation of the 5′-phosphate moiety. Thus, chemical phosphorylation of oligonucleotides (DNA or RNA) is achieved without using modified phosphoramidites.
THE PROTECTION OF 2'-HYDROXY FUNCTIONS IN OLIGORIBONUCLEOTIDE SYNTHESIS
Norman, G. David,Reese, B. Colin,Serafinowska, T. Halina
, p. 3015 - 3018 (1984)
The suitability of the 4-methoxytetrahydropyran-4-yl group for the protection of 2' ( or 3')-hydroxy functions in oligoribonucleotide synthesis is confirmed; the latter protecting group is removed in 0.01M-hydrochloric acid at room temperature under conditions which, contrary to a recent report, lead to no detectable cleavage or migration of the internucleotide phosphodiester linkages.
Chemical radiation studies of 8-bromoguanosine in aqueous solutions
Ioele, Marcella,Bazzanini, Rita,Chatgilialoglu, Chryssostomos,Mulazzani, Quinto G.
, p. 1900 - 1907 (2000)
Chemical radiolytic methods were used to investigate the reactions of hydrated electrons (eaq-) with 8-bromoguanosine (8-Br-Guo) as a function of pH. γ-Radiolysis of 8-Br-Guo in aqueous solutions followed by product studies showed the formation of guanosine (Guo) as a single product at various pH. In D2O solutions the quantitative incorporation of deuterium at the 8-position was also observed. Pulse radiolysis revealed the instantaneous formation of a guanosine radical cation (Guo.+ or its deprotonated forms) in acid or basic solutions. The same transient species results from the reaction of H. with 8-Br-Guo at pH 3, as well as from the reaction of (CH3)2CO.- with 8-Br-Guo at pH 13. In neutral solution, the initial electron adduct was rapidly protonated to give the first observable transient species that decays by first-order kinetics (k = 5 × 104 s-1) to produce the Guo(-H+). radical once again. Tailored experiments allowed the reaction mechanism to be defined in some detail.
Hydrolytic reactions of guanosyl-(3′,3′)-uridine and guanosyl-(3′,3′)-(2′,5′-di-O-methyluridine)
Kiviniemi, Anu,Loennberg, Tuomas,Ora, Mikko
, p. 11040 - 11045 (2004)
Hydrolytic reactions of guanosyl-(3′,3′)-uridine and guanosyl-(3′,3′)-(2′,5′-di-O-methyluridine) have been followed by RP HPLC over a wide pH range at 363.2 K in order to elucidate the role of the 2′-hydroxyl group as a hydrogen-bond donor upon departure of the 3′-uridine moiety. Under neutral and basic conditions, guanosyl-(3′,3′)-uridine undergoes hydroxide ion-catalyzed cleavage (first order in [OH-]) of the P-O3′ bonds, giving uridine and guanosine 2′,3′-cyclic monophosphates, which are subsequently hydrolyzed to a mixture of 2′- and 3′-monophosphates. This bond rupture is 23 times as fast as the corresponding cleavage of the P-O3′ bond of guanosyl-(3′,3′)-(2,5′-di-O-methyluridine) to yield 2′,5′-O-dimethyluridine and guanosine 2′,3′-cyclic phosphate. Under acidic conditions, where the reactivity differences are smaller, depurination and isomerization compete with the cleavage. The effect of Zn2+ on the cleavage of the P-O3′ bonds of guanosyl-(3′,3′)-uridine is modest: about 6-fold acceleration was observed at [Zn2+] = 5 mmol L-1 and pH 5.6. With guanosyl-(3′,3′)-(2′,5′-di-O-methyluridine) the rate-acceleration effect is greater: a 37-fold acceleration was observed. The mechanisms of the partial reactions, in particular the effects of the 2′-hydroxyl group on the departure of the 3′-linked nucleoside, are discussed.
A kinetic study of the rat liver adenosine kinase reverse reaction
Vannoni,Giglioni,Santoro,Aceto,Marinello,Leoncini
, p. 872 - 875 (2008)
Adenosine kinase is an enzyme catalyzing the reaction: adenosine + ATP → AMP + ADP. We studied some biochemical properties not hitherto investigated and demonstrated that the reaction can be easily reversed when coupled with adenosine deaminase, which transforms adenosine into inosine and ammonia. The overall reaction is: AMP + ADP → ATP + inosine + NH3. The exoergonic ADA reaction shifts the equilibrium and fills the energy gap necessary for synthesis of ATP. This reaction could be used by cells under particular conditions of energy deficiency and, together with myokinase activity, may help to restore physiological ATP levels. Copyright Taylor & Francis Group, LLC.
Kiteplatin: Differential binding between GSH and GMP
Petruzzella, Emanuele,Curci, Alessandra,Margiotta, Nicola,Natile, Giovanni,Hoeschele, James D.
, p. 130 - 136 (2016)
Glutathione (GSH) plays an important role in the development of resistance to platinum-based chemotherapy, since it can prevent drug binding to DNA and resulting apoptosis of tumor cells. The recently re-discovered drug candidate kiteplatin was found active toward cisplatin- and oxaliplatin-resistant tumor cells, and this could be related to a different interplay of drug-inactivation/DNA-interaction processes. In this study GSH and GMP have been chosen as simple models of platinophiles and DNA, respectively, and the reactivity of kiteplatin has been tested toward GMP, after previous interaction with GSH; toward GSH, after previous interaction with GMP; and toward GMP and GSH simultaneously.
1,1,1,3,3,3-Hexafluoro-2-propanol for the Removal of the 4,4'-Dimethoxytrityl Protecting Group from the 5'-Hydroxyl of Acid-Sensitive Nucleosides and Nucleotides
Leonard, Nelson J.,Neelima
, p. 7833 - 7836 (1995)
1,1,1,3,3,3-Hexafluoro-2-propanol is introduced as a suitable reagent and solvent for the detritylation of 5'-O-(4,4'-dimethoxytrityl)-nucleosides and -deoxy- nucleosides, especially those that are susceptible to N-glycosyl cleavage under more strongly acidic conditions.
