Intramolecular Nitrone Cycloaddition Reaction on Carbohydrate-Based Precursors: Application in the Synthesis of Spironucleosides and Spirobisnucleosides
作者:Kaushik Singha、Atanu Roy、Pradeep K. Dutta、Subhankar Tripathi、Sk. Sahabuddin、Basudeb Achari、Sukhendu B. Mandal
DOI:10.1021/jo035813v
日期:2004.9.1
A simple synthesis of chiral spironucleosides and spirobisnucleosides is described. Intramolecular 1,3-dipolar nitrone cycloaddition reaction of d-glucose-derived precursors having olefin at C-3 and nitrone at C-5, C-1, or C-2 (in nor-series) furnished bisisoxazolidinospirocycles 4−7, 11, and 12 in good yields. Reductive ring opening of the isoxazolidine moieties in 4−6 followed by construction of
描述了手性螺核苷和螺双核苷的简单合成。分子内的1,3-偶极环加成硝酮反应d具有烯烃在C-3和硝酮在C-5,C-1或C-2 -葡萄糖衍生的前体(在也不系列)布置bisisoxazolidinospirocycles 4 - 7,11和12个高产。在异恶唑烷部分的还原性开环4 - 6所生成的氨基基团,然后结构的核苷碱基的顺利产生spirobisnucleosides 17和18和spironucleosides 20和21。