title: Synthesis of 5-hydroxy-2-(beta-D-ribofuranosyl)pyran-4-one from a pyranulose glycoside.
abstract: The synthesis of 5-hydroxy-2-(beta-D-ribofuranosyl)pyran-4-one (9) is described. Treatment of pyranulose glycoside with bromine in carbon tetrachloride afforded brompyranulose glycoside in 90% yield. The reaction of (6S)- and (6R)-4-bromo-6-hydroxy-6-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)-6H- pyran-3-one (2) in acidic media was examined with the following results: the reaction of 2 with trifluoroacetic acid (TFA) in dioxane afforded a mixture of 5-hydroxy-2-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)pyran-4-one (3) and its furan derivative 5-hydroxy-2-{5-(benzoyloxy)methyl]furan-2-yl}pyran-4-one (4), but the use of hydrochloric acid formed the bromofurfural, 3-bromo-5-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)-2-furancarboxyal dehyde only. Acetylation of a mixture (3 and 4) with acetic anhydride facilitated product separation to give the corresponding acetates 5-acetoxy-2-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)pyran-4-one (5) and 5-acetoxy-2-{5-[(benzoyloxy)methyl]furan-2-yl}pyran-4-one (6). Treatment of 5 with hydrazine afforded 3-hydroxymethyl-6-(beta-D-ribofuranosyl)-1H-pyridazin-4-one in 43% yield. Debenzoylation of 5 with aq ammonia gave 9 in 50% yield.
authors.affiliation: Faculty of Pharmacy, Meijo University, Nagoya, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kanazawa
authors.forename: S
authors.initials: S
authors.lastname: Mizuno
authors.forename: R
authors.initials: R
authors.lastname: Yamauchi
authors.forename: N
authors.initials: N
authors.lastname: Nishimura
authors.forename: I
authors.initials: I
authors.lastname: Maeba
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002867:Chromones / Q000737:chemistry; D006027:Glycosides; D007202:Indicators and Reagents; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010080:Oxazoles / Q000737:chemistry; D011753:Pyrones / Q000138:chemical synthesis* / Q000737:chemistry; D012266:Ribose / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D016339:Spectrometry, Mass, Fast Atom Bombardment
chemical_list: C122026:5-hydroxy-2-(beta-ribofuranosyl)pyran-4-one; D000900:Anti-Bacterial Agents; D002867:Chromones; D006027:Glycosides; D007202:Indicators and Reagents; D010080:Oxazoles; D011753:Pyrones; C077638:phenoxan; D012266:Ribose; C012198:aureothin