Stereoselective Synthesis of 2-Deoxy-2-iodo-glycosides from Furanoses. A New Route to 2-Deoxy-glycosides and 2-Deoxy-oligosaccharides of <i>r</i><i>ibo </i>and <i>x</i><i>ylo</i> Configuration
作者:Miguel Ángel Rodríguez、Omar Boutureira、Xavier Arnés、M. Isabel Matheu、Yolanda Díaz、Sergio Castillón
DOI:10.1021/jo051461b
日期:2005.12.1
procedure involves three reactions: Wittig−Horner olefination to give alkenyl sulfanyl derivatives, electrophilic iodine-induced cyclization to give phenyl 2-deoxy-2-iodo-1-thio-hexo-glycosides, and glycosylation. Protected furanoses 1, 3, and 6−11, which include examples of the four possible isomeric configurations of furanoses, were reacted with diphenyl phenylsulfanylmethyl phosphine oxide to give the
据报道从呋喃糖酶立体选择性合成2-脱氧-2-碘-己-和-庚-吡喃糖基糖苷的一般方法。拟议的方法提供了一种获取2-脱氧寡糖的新途径。该程序涉及三个反应:Wittig-Horner烯化生成链烯基硫烷基衍生物,亲电碘诱导的环化生成苯基2-脱氧-2-碘-1-硫代-己糖苷,以及糖基化。保护呋喃糖1,3,和6 - 11,其包括呋喃糖的四种可能的异构体构型的实施例中,与碳酸二苯苯基硫基甲基氧化膦,得到链烯基硫烷基衍生物进行反应2,4,和12− 16。这些化合物,得到苯基2-脱氧-2-碘-1-硫代糖苷的碘诱导的环化18,20,和22 - 27具有实际上完全区域选择性和立体选择性。6-产品内的环化,其中在C-2中的碘是一个顺式在C-3与烷氧基的关系,进行了几乎全部产生。具有核糖或木糖构型的化合物比具有其他构型的化合物获得更好的产率。化合物18,20,和22 - 27已发现在胆固醇和吡喃葡萄糖苷29a的糖基化