Additive Pummerer Reaction of 3,5-O-(Di-tert-butyl)silylene-4-thiofuranoid Glycal: A High-Yield and β-Selective Entry to 4′-Thioribonucleosides

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• 作者：Kazuhiro Haraguchi* ; Hiromitsu Matsui ; Shin Takami ; Hiromichi Tanaka
• 刊名：Journal of Organic Chemistry
• 出版年：2009
• 出版时间：March 20, 2009
• 年：2009
• 卷：74
• 期：6
• 页码：2616-2619
• 全文大小：170K
• 年卷期：v.74,no.6(March 20, 2009)
• ISSN：1520-6904

文摘

Upon reacting 3,5-O-(di-tert-butyl)silylene-4-thiofuranoid glycal S-oxide (6) with Ac₂O/TMSOAc/BF₃·OEt₂ in CH₂Cl₂, the additive Pummerer reaction proceeded to furnish the corresponding 1,2-di-O-acetyl-4-thioribofuranose 7. Compound 7 serves as a highly β-selective glycosyl donor in the Vorbrggen condensation carried out in the presence of TMSOTf. Thus, the 4-thio-β-d-ribofuranosyl derivatives of uracil, thymine, N(4)-acetylcytosine, 6-chloropurine, and 2-amino-6-chloropurine were synthesized. The use of 7 can be extended to the β-selective synthesis of 4′-thio-C-ribonucleosides.