Revisiting the Armed−Disarmed Concept Rationale: <i>S</i>-Benzoxazolyl Glycosides in Chemoselective Oligosaccharide Synthesis
作者:Medha N. Kamat、Alexei V. Demchenko
DOI:10.1021/ol050969y
日期:2005.7.1
2-O-benzyl-3,4,6-tri-O-acyl SBox glycosides are significantly less reactive than even "disarmed" peracylated derivatives. This finding has been applied to the synthesis of various oligosaccharides, the monomeric units of which are connected via cis-cis, trans-cis, and cis-trans sequential glycosidic linkages. Two-stage activation of the armed (benzylated) donor over moderately (dis)armed (acylated) and, subsequently
[反应:请参见文字]。已经发现2-O-苄基-3,4,6-三-O-酰基SBox糖苷的反应性甚至比“解除武装的”过酰化衍生物低得多。该发现已应用于合成各种寡糖,其单体单元通过顺式-顺式,反式-顺式和顺式-顺式顺序的糖苷键连接。事实证明,在中等程度的(解除)武装(酰化)以及随后的解除武装的(2-O-苄基-3,4-O-二酰化)受体上的两步活化(苄基化)供体也是可行的。