A Novel Stereospecific Synthesis of Glycosyl Cyanides from 1,2-<i>O</i>-Sulfinyl Derivatives
作者:Abdelhafid Benksim、Daniel Beaupère、Anne Wadouachi
DOI:10.1021/ol0486829
日期:2004.10.1
[reaction: see text] An efficient synthesis of 1,2-trans-glycosyl cyanides via 1,2-O-sulfinyl monosaccharides is described. Such S(N)2-type displacements at the anomeric center are stereospecific and are best performed with sodium cyanide in the presence of ytterbium triflate. Significantly, the resulting 1,2-trans-glycosyl cyanides have a free hydroxyl group at C-2 ready for further modification.
[反应:见正文]描述了通过1,2-O-亚磺酰基单糖有效合成1,2-反式-糖基氰化物。在端基异构中心的此类S(N)2型置换具有立体定向性,最好在三氟f磺酸presence存在下用氰化钠进行。明显地,所得的1,2-反式-糖基氰化物在C-2处具有游离羟基,准备进一步修饰。