ethyl 2,3,4-tri-O-benzyl-6-O-chloroacetyl-1-thio-α/β-D-galactopyranoside

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: ethyl 2,3,4-tri-O-benzyl-6-O-chloroacetyl-1-thio-α/β-D-galactopyranoside
• 英文别名: [(2R,3S,4S,5R)-6-ethylsulfanyl-3,4,5-tris(phenylmethoxy)oxan-2-yl]methyl 2-chloroacetate
• 化学式: C₃₁H₃₅ClO₆S
• 分子量: 571.134
• InChiKey: KEEPGKQBJOZDFV-IWHCUQKTSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.8
• 重原子数：
  39
• 可旋转键数：
  15
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.39
• 拓扑面积：
  88.5
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  ethyl 2,3,4-tri-O-benzyl-6-O-chloroacetyl-1-thio-α/β-D-galactopyranoside 、 扁桃酸苄酯 在 N-碘代丁二酰亚胺 、 三氟甲磺酸 作用下， 以 二氯甲烷 为溶剂， 反应 0.08h， 以70%的产率得到benzyl (2S)-2-O-(2,3,4-tri-O-benzyl-6-O-chloroacetyl-α-D-galactopyranosyl)-2-phenylacetate
  参考文献：
  名称：

  The effect of electron withdrawing protecting groups at positions 4 and 6 on 1,2-cis galactosylation

  摘要：

  Ethyl 2,3,4-O-tribenzyl-6-O-chloroacetyl-1-D-thiogalactoside, phenyl 4,6-O-diacetyl-2,3-dibenzyl-1-D-thiogalactoside and phenyl 2,3-O-dibenzyl-4,6-O-dichloroacetyl-1-D-thiogalactoside were employed in the study of the stereoselectivity of the glycosylation reaction with several acceptors, ranging from unhindered linear primary alcohols to other sugars, using NIS/TfOH as activator. Higher alpha-selectivities were obtained in the glycosylation reactions with phenyl 2,3-O-dibenzyl-4,6-O-dichloroacetyl-1-D-thiogalactoside as the donor, showing that a stronger electron withdrawing 4-O-ester group had an influence in the anomeric selectivity favouring the formation of 1,2-cis galactosides. (C) 2013 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2013.06.038

文献信息

• The effect of electron withdrawing protecting groups at positions 4 and 6 on 1,2-cis galactosylation
  作者：Eva C. Lourenço、M. Rita Ventura

  DOI：10.1016/j.tet.2013.06.038

  日期：2013.8

  Ethyl 2,3,4-O-tribenzyl-6-O-chloroacetyl-1-D-thiogalactoside, phenyl 4,6-O-diacetyl-2,3-dibenzyl-1-D-thiogalactoside and phenyl 2,3-O-dibenzyl-4,6-O-dichloroacetyl-1-D-thiogalactoside were employed in the study of the stereoselectivity of the glycosylation reaction with several acceptors, ranging from unhindered linear primary alcohols to other sugars, using NIS/TfOH as activator. Higher alpha-selectivities were obtained in the glycosylation reactions with phenyl 2,3-O-dibenzyl-4,6-O-dichloroacetyl-1-D-thiogalactoside as the donor, showing that a stronger electron withdrawing 4-O-ester group had an influence in the anomeric selectivity favouring the formation of 1,2-cis galactosides. (C) 2013 Elsevier Ltd. All rights reserved.