- Open-Close Strategy toward the Organocatalytic Generation of 2-Deoxyribosyl Oxocarbenium Ions: Pyrrolidine-Salt-Catalyzed Synthesis of 2-Deoxyribofuranosides
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The reaction of secondary amine salts with 2-deoxy-ribofuranoses under forcible conditions leads to the putative furanosyl oxocarbenium ion that is trapped with various alcohols to provide 2-deoxy-ribofuranosides. The observed anomeric selectivities range from an equimolar mixture to complete α-selectivity in the case of bulky sugar acceptors. Owing to the mechanism and temperature of the transformation, the generated oxocarbenium ion shows little or no facial preference towards the nucleophilic attack of non-carbohydrate acceptors and leads to a mixture of anomers in the case of benzyl and acetyl protected donors. However, the conformationally less flexible tetraisopropylsilyl protected donor reacted with both sugar and non-sugar acceptors in a stereoselective fashion. Besides, the glycosylation with 2-cyanoethanol gave the product with unexpected beta-selectivity presumably due to nitrile effect. The operationally simple organocatalytic protocol provides easy access to otherwise difficult 2-deoxy-ribofuranosides/disaccharides.
- Ghosh, Titli,Mukherji, Ananya,Kancharla, Pavan K.
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supporting information
p. 7488 - 7498
(2019/11/29)
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- Synthesis of 2-deoxy ribose related disaccharide nucleoside and its phosphoramidite
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Synthesis of impurity reference compound of anti-tumor drug ISIS 183750 was achieved. In this process, a general method for synthesis of 2-deoxy ribosyl disaccharide nucleosides was established for the first time.
- Ding, Yili,Deng, Rilie,Wang, Bingyun
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p. 3848 - 3852
(2017/06/13)
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- PROCESS FOR THE PREPARATION OF (2R.3S)-2-(HYDROXYMETHYL) -5-METHOXYTETRAHYDROFURAN-3-OL AND ACETYLATED DERIVATIVES THEREOF, FREE OF PYRANOSE COMPOUNDS
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A method of preparing a ribofuranose derivative essentially free of pyranose compounds includes a step of contacting a solution of MDR containing MDRP as an impurity in a solvent including methanol and/or tetrahydrofuran with at least one alkali metal periodate under conditions sufficient to oxidize at least a portion of the MDRP. MDR containing at most 5 wt% of MDRP based on the total weight of MDR and MDRP may be produced.
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- PREPARATION OF DECITABINE
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The present application relates to processes for the preparation and purification of decitabine, and to processes for the preparation of a crystalline form of decitabine.
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Page/Page column 25-26
(2010/11/18)
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- Indium-Mediated Allylation of Aldehydes: A Convenient Route to 2-Deoxy and 2,6-Dideoxy Carbohydrates
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The allylation of protected polyhydroxy aldehydes 1 and 14 has been achieved by indium metal with ultrasound promotion generating the diastereomeric pair of homoallylic polyols 3, 4 and 16, 17 respectively with moderate to good stereoselectivity.Pursuing this allylation strategy with the corresponding deprotected polyhydroxy aldehydes led to the same pair of homoallylic polyols but with a quite different ratio of the diastereomers generated.The polyols were further transformed to 2-deoxy (5 and 6) and 2,6-dideoxy (18 and 19) carbohydrates by ozonolysis.
- Binder, Wolfgang H.,Prenner, Reinhard H.,Schmid, Walther
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p. 749 - 758
(2007/10/02)
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- Stereocontrolled Synthesis of β-D-2'-Deoxyribonucleosides by Intramolecular Glycosylation
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Intramolecular glycosylation of phenyl 2-deoxy-5-O-(2-pyridyl)- and 2-deoxy-5-O-(4-methoxy-2-pyrimidyl)-1-thio-D-ribofuranoside by activation with dimethyl(methylthio)sulfonium tetrafluoroborate followed by hydrolysis gave the corresponding β-2'-deoxyribo
- Sujino, Keiko,Sugimura, Hideyuki
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p. 1187 - 1190
(2007/10/02)
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- Synthesis and biological activity of 5-(2,2-difluorovinyl)-2'-deoxyuridine
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5-(2,2-Difluorovinyl)uracil (IV) was synthesized from 2,4-dimethoxy-5-bromopyrimidine by sequential formylation, difluoromethylenation, and removal of the 2- and 4-methyl groups. Condensation of the trimethylsilyl derivative of IV with protected D-erythro-pentofuranosyl chloride followed by separation of anomers and deblocking gave 5-(2,2-difluorovinyl)-2'-deoxyuridine (V). Compound V was active against herpes simplex virus type 1 (HSV-1) infection as well as tumor cells transformed by the HSV-1 thymidine kinase gene.
- Bobek,Kavai,De Clercq
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p. 1494 - 1497
(2007/10/02)
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