Synthesis of C-glycosides via radical cyclization reactions with a vinylsilyl tether. Control of the reaction course by a change in the conformation of the pyranose ring due to steric repulsion between adjacent bulky protecting groups
作者:Yumi Yahiro、Satoshi Ichikawa、Satoshi Shuto、Akira Matsuda
DOI:10.1016/s0040-4039(99)01026-6
日期:1999.7
and 1β-postions of d-glucose and d-mannose, respectively, via a radical cyclization reaction with vinylsilyl group as a temporary connecting tether, was developed. The radical cyclization of d-glucose substrates was effectively facilitated by a change in the conformation of the pyranose ring into a 1C4-form due to steric repulsion between adjacent bulky TBS-protecting groups.
开发了一种立体选择性的方法,该方法通过乙烯基乙烯基作为临时连接链的自由基环化反应,分别在d-葡萄糖和d-甘露糖的1α-和1β-位引入C2-单元。通过由于相邻的大体积TBS-保护基团之间的空间排斥而使吡喃糖环的构型改变为1 C 4-形式,有效地促进了d-葡萄糖底物的自由基环化。