Acetylation and cleavage of purine nucleosides. Synthesis of 6-azauridine, 5-fluorouridine, and 5-methyluridine.
AUTOR(ES)
Beránek, J
RESUMO
Inosine (I) when acetylated with acetic anhydride in the presence of acetyl chloride in acetic acid solution (the so called "acid acetylation"), affords an acetylated nucleoside III (75%) along with cleavage products of the nucleoside (hypoxanthine, 19%). The reaction of I with acetyl chloride (7 days) results in the formation of hypoxanthine (95%) and triacetylribofuranosyl chloride (IV) isolated in the form of tetraacetylribofuranose (47%). The acetylated purine nucleoside affords a similar result by reaction with acetyl chloride or acetyl bromide. 2'-Deoxyuridine gives a diacetyl derivative (80%) by reaction with acetyl bromide. On treatment with acetyl bromide, the nucleoside bond of purine nucleosides is quantitatively cleavaged (4 h, 20 degrees C) with the formation of tri-O-acetyl-D-ribofuranosyl bromide (X). The halogenose X affords pure beta-anomers, namely, 1,2,3,5-tetra-O-acetyl-beta-D-ribofuranose (75%), the triacetyl derivatives of 5-methyluridine (XVIIa; 75%, referred to guanosine), 6-azauridine (XVIII; 71%), and 5-fluorouridine (XIXa; 75%).
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=342993Documentos Relacionados
- 5'-Halogeno-2',3'-cyclic sulphite isomers in the preparation of 5'-halogeno nucleosides. Synthesis of 5'-deoxyuridine and 5'-deoxy-5-fluorouridine.
- Comparative study by circular dichroism of the conformation of deazapurine nucleosides and that of common purine nucleosides.
- Glycosyl conformational and inductive effects on the acid catalysed hydrolysis of purine nucleosides.
- A new synthesis of 5'-deoxy-8,5'-cyclo-adenosine and -inosine: conformationally-fixed purine nucleosides (nucleosides and nucleotides. XVI).
- A convenient synthesis of 6-amino-1-beta-D-ribofuranosylpyrazolo[3,4-d]pyrimidin-4-one and related 4,6-disubstituted pyrazolopyrimidine nucleosides.