Vinyl glycosides in oligosaccharide synthesis .2. The use of allyl and vinyl glycosides in oligosaccharide synthesis
Vinyl glycosides in oligosaccharide synthesis .2. The use of allyl and vinyl glycosides in oligosaccharide synthesis
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DOI：
10.1021/jo960131b
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发表时间：
1996-06-28
影响因子：
3.6
通讯作者：
Isles, S
中科院分区：
文献类型：
--
作者：
Boons, GJ;Isles, S
已经描述了一种新的潜在活性糖基化策略，其依赖于取代的烯丙基糖苷的异构化以得到相应的乙烯基糖苷，其随后可用于刘易斯酸介导的糖基化。异构化反应通过用正丁基锂处理三（三苯基膦）氯化铑（I）得到的铑催化剂进行。该催化剂具有许多优于使用常规威尔金森催化剂的优点。糖基化反应得到了高收率的伯和仲糖醇，和异头选择性可以控制的糖基供体的组成和反应条件。新的异构化和糖基化方法使具有生物重要性的复杂寡糖能够以高度收敛的方式制备。
A novel latent-active glycosylation strategy has been described that relies on the isomerization of substituted allyl glycosides to give the corresponding vinyl glycosides, which can subsequently be used in Lewis acid-mediated glycosylations. The isomerization reaction was performed by a rhodium catalyst obtained by treating tris(triphenylphosphine)rhodium(I) chloride with n-butyllithium. This catalyst has many advantageous properties over the use of conventional Wilkinson's catalyst. The glycosylation reactions gave high yields for both primary and secondary sugar alcohols, and the anomeric selectivity could be controlled by the constitution of the glycosyl donor and reaction conditions. The new isomerization and glycosylation approach enables complex oligosaccharides of biological importance to be prepared in a highly convergent manner.