820212-19-9Relevant academic research and scientific papers
Efficient synthesis of exo-N-carbamoyl nucleosides: Application to the synthesis of phosphoramidate prodrugs
Cho, Jong Hyun,Coats, Steven J.,Schinazi, Raymond F.
supporting information; experimental part, p. 2488 - 2491 (2012/08/27)
An efficient protection protocol for the 6-exo-amino group of purine nucleosides with various chloroformates was developed utilizing N-methylimidazole (NMI). The reaction of an exo-N6-group of adenosine analogue 1 with alkyl/and aryl chloroformates under optimized conditions provided the N6-carbamoyl adenosines (2a-j) in good to excellent yields. The reaction of N6-Cbz-protected nucleosides (5a-c) with phenyl phosphoryl chloride (7) using t-BuMgCl followed by catalytic hydrogenation afforded the corresponding phosphoramidate pronucleotides (8a-c) in excellent yield.
NOVEL PROTECTING GROUP FOR SYNTHESIZING RNA AND DERIVATIVE THEREOF
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, (2012/07/30)
A protective group represented by the following general formula (I) (the oxygen atom attached with * represents oxygen atom of 2'-hydroxyl group of a ribonucleoside, a ribonucleotide or a derivative thereof, R1 and R2 both represent hydrogen atom, or represent a halogen atom, a C1-6 alkyl group, or a C1-6 halo-substituted alkyl group; R3 and R4 represent hydrogen atom, a halogen atom, a C1-6 alkyl group, or a C1-6 halo-substituted alkyl group; and R5 and R6 represent a halogen atom, a C1-6 halo-substituted alkyl group, cyano group, nitro group, or the like), which is stable under the reaction conditions of the nucleic acid synthetic cycles and has little steric hindrance, and can be removed under mild conditions using fluoride ions as a base.
Efficient synthesis of nucleoside aryloxy phosphoramidate prodrugs utilizing benzyloxycarbonyl protection
Cho, Jong Hyun,Amblard, Franck,Coats, Steven J.,Schinazi, Raymond F.
experimental part, p. 5487 - 5493 (2011/08/06)
An efficient method for the synthesis of nucleoside phosphoramidates prodrugs (6a-f) has been developed that employs a simple protection/deprotection sequence of the nucleoside with benzyloxycarbonyl (Cbz). The coupling reaction of Cbz-protected derivativ
Simultaneous removal of benzyl and benzyloxycarbonyl protective groups in 5′-O-(2-deoxy-α-D-glucopyranosyl)uridine by catalytic transfer hydrogenolysis
Wandzik, Ilona,Bieg, Tadeusz,Kadela, Monika
body text, p. 1250 - 1256 (2009/04/06)
Synthesis of N3,2′,3′-O-tris-(benzyloxycarbonyl)uridine and its use in the synthesis of 5′-O-(2-deoxy-α-d-glucopyranosyl)uridine is described. Simultaneous removal of benzyl and benzyloxycarbonyl groups was accomplished by catalytic transfer hydrogenolysis in the presence of Pearlman′s catalyst without competing side reactions. Copyright Taylor & Francis Group, LLC.
Facile deprotection of O-Cbz-protected nucleosides by hydrogenolysis: An alternative to O-benzyl ether-protected nucleosides
Johnson II, David C.,Widlanski, Theodore S.
, p. 4643 - 4646 (2007/10/03)
(Chemical Equation Presented) Because of side-reactions encountered during hydrogenolysis, benzyl ethers are usually not an effective protecting group for nucleosides. Benzyloxycarbamates provide an alternative to traditional benzyl ethers for protection of nucleoside hydroxyl groups, as they are much more labile to hydrogenolysis. Deprotection conditions using transfer hydrogenolysis are described that avoid the reduction of the pyrimidine nucleobase during deblocking of O-Cbz-protected nucleosides. Additionally, an experiment is described that suggests the nucleobase component of a nucleoside is responsible for the sluggish hydrogenolysis of nucleosides.
