| Autor: |
Dimitri Komiotis, Niki Tzioumaki, Stella Manta, Evangelia Tsoukala, Christos Kiritsis |
| Rok vydání: |
2011 |
| Předmět: |
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| Zdroj: |
Carbohydrate Research. 346:2011-2015 |
| ISSN: |
0008-6215 |
| Popis: |
A novel series of fluorinated keto-β- d -5-thioxylopyranonucleosides bearing thymine as the heterocyclic base have been designed and synthesized. Deprotection of 3-deoxy-3-fluoro-5- S -acetyl-5-thio- d -xylofuranose ( 1 ) and selective acetalation gave the desired isopropylidene 5-thioxylopyranose precursor 3 . Acetylation and isopropylidene removal followed by benzoylation led to 3-deoxy-3-fluoro-1,2-di- Ο -benzoyl-4- O -acetyl-5′-thio- d -xylopyranose ( 6 ). This was condensed with silylated thymine and selectively deacetylated to afford 1-(2′- Ο -benzoyl-3′-deoxy-3′-fluoro-5′-thio-β- d -xylopyranosyl)thymine ( 8 ). Oxidation of the free hydroxyl group in the 4′-position of the sugar led to the formation of the target 4′-keto compound together with the concomitant displacement of the benzoyl group by an acetyl affording, 1-(2′- O -acetyl-3′-deoxy-3′-fluoro-β- d -xylopyranosyl-4′-ulose)thymine ( 9 ). Benzoylation of 3 and removal of the isopropylidene group followed by acetylation, furnished 3-deoxy-3-fluoro-1,2-di- Ο -acetyl-4- O -benzoyl-5′-thio- d -xylopyranose ( 12 ). Condensation of thiosugar 12 with silylated thymine followed by selective deacetylation led to the 1-(4′- Ο -benzoyl-3′-fluoro-5′-thio-β- d -xylopyranosyl)thymine ( 14 ). Oxidation of the free hydroxyl group in the 2′-position and concomitant displacement of the benzoyl group by an acetyl gave target 1-(4′- O -acetyl-3′-deoxy-3′-fluoro-β- d -xylopyranosyl-2′-ulose)thymine ( 15 ). |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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