title: Conversion of 2-deoxy-D-ribose into 2-amino-5-(2-deoxy-beta-D-ribofuranosyl)pyridine, 2'-deoxypseudouridine, and other C-(2'-deoxyribonucleosides).
abstract: The synthesis of 2-amino-5-(2-deoxy-beta-D-ribofuranosyl)pyridine 2a, 2-amino-5-(2-deoxy-alpha-D-ribofuranosyl)-pyridine 23, 2-amino-5-(2-deoxy-beta-D-ribofuranosyl)-3-methylpyridine 2b, 2-amino-5-(2-deoxy-alpha-D-ribofuranosyl)-3-methylpyridine 29 and 5-(2-deoxy-beta-D-ribofuranosyl)-2,4-dioxopyrimidine [2'-deoxypseudouridine] 30a is described. These C-nucleosides are prepared either from 2-deoxy-3,5-O-(1,1,3,3-tetraisopropyldisiloxan-1,3-diyl)-D-ribofuranose 15 or from 2-deoxy-3,5-O-(1,1,3,3-tetraisopropyldisiloxan-1,3-diyl)-D-ribono-1,4-lactone 16, which are themselves prepared from 2-deoxy-D-ribose 13. The sugar derivatives are first allowed to react with the appropriate 5-lithio-pyridine or 5-lithio-pyrimidine derivatives, which are prepared from 5-bromo-2-(dibenzylamino)pyridine 12a, 5-bromo-2-[bis(4-methoxybenzyl)amino]pyridine 12b, 5-bromo-2-dibenzylamino-3-methylpyridine 25 and 5-bromo-2,4-bis(4-methoxybenzyloxy)pyrimidine 33. The products from the reactions between the lithio-derivatives and the lactol 15 are cyclized under Mitsunobu conditions; the products from the reactions between the lithio-derivatives and the lactone 16 are first reduced with L-Selectride before cyclization, also under Mitsunobu conditions. In all cases, the beta-anomers of the protected C-nucleosides are the predominant products. Finally, the separation of the alpha- and beta-anomers and the removal of all of the protecting groups are described.
authors.affiliation: Department of Chemistry, King's College London, Strand, London, UK WC2R 2LS. colin.reese@kcl.ac.uk
authors.forename: Colin B
authors.initials: CB
authors.lastname: Reese
authors.forename: Qinpei
authors.initials: Q
authors.lastname: Wu
mesh_terms: D002241:Carbohydrates / Q000737:chemistry; D003853:Deoxyribonucleosides / Q000737:chemistry*; D003854:Deoxyribonucleotides / Q000737:chemistry*; D003855:Deoxyribose / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry*; D013696:Temperature
chemical_list: D002241:Carbohydrates; D003853:Deoxyribonucleosides; D003854:Deoxyribonucleotides; D011725:Pyridines; D003855:Deoxyribose