Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States.
J Org Chem. 2012 Jan 6;77(1):291-9. doi: 10.1021/jo2019174. Epub 2011 Dec 21.
Elaborating on previous studies by Lemieux for highly reactive "armed" bromides, we discovered that β-bromide of the superdisarmed (2-O-benzyl-3,4,6-tri-O-benzoyl) series can be directly obtained from the thioglycoside precursor. When this bromide is glycosidated, α-glycosides form exclusively; however, the yields of such transformations may be low due to the competing anomerization into α-bromide that is totally unreactive under the established reaction conditions.
在 Lemieux 对高反应性“武装”溴化物的先前研究的基础上，我们发现超去保护（2-O-苄基-3,4,6-三-O-苯甲酰基）系列的β-溴化物可以直接从硫代糖苷前体中获得。当这种溴化物进行糖苷化时，只会形成α-糖苷；然而，由于竞争的差向异构化生成完全无反应性的α-溴化物，这种转化的产率可能较低，而这种异构化在既定的反应条件下是无法进行的。
