54618-06-3Relevant academic research and scientific papers
Compositions and Methods for Reverse Automated Nucleic Acid Synthesis
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Paragraph 0102-0103, (2019/10/29)
Methods for reverse automated nucleic acid synthesis, and 5′-H-phosphonates suitable for use in the same, as well as methods for making 5′-H-phosphonates, are described.
Selective deacylation of peracylated ribonucleosides
Rigoli, Jared W.,?stergaard, Michael E.,Canady, Kirsten M.,Guenther, Dale C.,Hrdlicka, Patrick J.
supporting information; experimental part, p. 1751 - 1753 (2009/07/05)
A protocol for chemoselective deprotection of N,O-acylated ribonucleosides has been developed. Peracylated pyrimidine ribonucleosides subjected to guanidinium nitrate and NaOMe in MeOH/CH2Cl2 at 0 °C undergo high yielding O-deacylation, while even more pronounced chemoselectivity is observed with peracylated purine ribonucleosides as O5′-acyl groups are preserved. Nucleobase-protecting groups (ABz, CBz, GiBu, and UBz) are stable to these conditions, rendering this reagent mixture as a valuable addition to the collection of protecting group protocols in nucleoside chemistry.
Photochemical generation and reactivity of the 5,6-dihydrouridin-6-yl radical
Newman, Cory A.,Resendiz, Marino J. E.,Sczepanski, Jonathan T.,Greenberg, Marc M.
experimental part, p. 7007 - 7012 (2009/12/24)
(Chemical Equation Presented) Nucleobase radicals are the major family of reactive intermediates formed when nucleic acids are exposed to hydroxyl radical, which is produced by γ-radiolysis and Fe·EDTA. Significant advances have been made in understanding the role of nucleobase radicals in oxidative DNA damage by independently generating these species from photochemical precursors. However, this approach has been used much less frequently to study RNA molecules. Norrish type I photocleavage of the tert-butyl ketone (2b) enabled studying the reactivity of 5′-benzoyl-5,6- dihydrouridin-6-yl (1b). High mass balances were observed under aerobic or anaerobic conditions, and O2 did not affect the photochemical conversion of the ketone (2b) to 1b. Competition studies with O2 indicate that the radical abstracts hydrogen atoms from β-mercaptoethanol with a bimolecular rate constant = 2.6 ± 0.5 × 106 M-1s-1. The major product formed in the presence of O 2 was 5′-benzoyl-6-hydroxy-5,6-dihydrouridine (6). In contrast, 5-benzoyl-ribonolactone (7), a hypothetical product resulting from C1′-hydrogen atom abstraction by the peroxyl radical, could not be detected. Overall, tert-butyl ketone 2b is a clean source of 5′-benzoyl-5,6-dihydrouridin-6-yl (1b) and should prove useful for studying the reactivity of the respective radical in RNA.
The chemistry of 2′,3′-seconucleosides IV. Synthesis and reactions of 3′-azido-2′,3′-dideoxy-2′,3′- secothymidine and related analogues
Kumar, Ajit,Walker, Richard T.
, p. 3101 - 3110 (2007/10/02)
The synthesis of a series of 2,3-seconucleoside analogues related to nucleosides previously shown to possess anti-HIV activity is described. Using strategies to distinguish between the three primary hydroxyl groups of a 2,3-seconucleoside, 3-azido-2,3-dideoxy-2,3-secothymidine and 2,3-dideoxy-2,3-secothymidine have been prepared. These compounds, several of the intermediates in their synthesis, as well as O22-anhydro-3-azido-3-deoxy-2,3-secothymidine and several 2,3-secouridine analogues have been tested for their ability to prevent infection of cells by HIV. None showed any significant toxicity or antiviral activity.
PARTIAL PROTECTION OF CARBOHYDRATE DERIVATIVES. PART 18. SIMPLE, PREPARATIVE PROCEDURE FOR 5'-O-ACYLRIBONUCLEOSIDES; HIGHLY REGIOSELECTIVE O-DEACyLATION AT 2' AND 3' POSITIONS OF FULLY ACYLATED PURINE AND PYRIMIDINE RIBONUCLEOSIDE THROUGH SODIUM METHOXYDE-THF SYSTEM
Nishino, Shigeyoshi,Rahman, MD. Azizur,Takamura, Hatsuko,Ishido, Yoshiharu
, p. 5503 - 5506 (2007/10/02)
A treatment of fully acylated purine and pyrimidine ribonucleosides with a small excess amount of sodium methoxide in THF at room temperature gave the corresponding 5'-acylates in excellent yields; N-acyl groups on the nucleic acid base moieties of adenosine and cytidine in addition to guanosine derivatives satisfactorily survived under the conditions used.
Partial Protection of Carbohydrate Derivatives. Part 4. Regioselective 2'-O-Deacylation of Fully Acylated Purine and Pyrimidine Ribonucleosides with Hydroxylaminium Acetate
Ishido, Yoshiharu,Sakairi, Nobuo,Okazaki, Kei,Nakazaki, Nobuo
, p. 563 - 573 (2007/10/02)
Like hydrazine hydrate, hydroxylamine was found to be useful for the regioselective 2'-O-deacylation of fully acylated purine and pyrimidine ribonucleosides as its salt with acetic acid; the partial O-deacylation reactions (which were not accompanied by undesirable discolouration as happens with hydrazine hydrate) gave the corresponding di-O-acylribonucleosides in superior yields; e.g. 2',3'-di-O-benzoyladenosine (74percent yield), 3',5'- (64percent yield) and 2',5'-di-O-benzoyl-N6-benzyladenosine (63percent yield on performing the reaction in ethanol), N2,3',5'-tri-O-benzoylguanosine (66percent yield), N2,2',5'-tri-isobutyrylguanosine (48percent yield), and 3',5'-di-O-benzoyluridine (61percent yield) were obtained using hydroxylaminium acetate in pyridine.Treatment of fully acetylated ribonucleosides with an excess of hydroxylaminium acetate gave the corresponding 5'-O-acetylribonucleosides in quantitative yields.The excellent regioselectivity observed in the present partial O-decyclation was confirmed on the basis of chromatographic separation; the mixtures of di-O-acylribonucleosides, which had already been equilibrated in pyridine, were re-equilibrated on the silica gel during separation, e.g. a 70 : 30 mixture of 3',5'- and 2',5'-di-O-benzoyladenosine was completely converted into the former based on 1H n.m.r spectroscopy.The acetates of 9-β-D-xylo- and -arabino-furanosyladenine were also found to give predominantly the corresponding 3',5'-diacetates on hydroxylaminolysis.
