phenyl 4,6-di-O-acetyl-2,3-di-O-benzyl-1-thio-β-D-galactopyranoside | 911684-18-9

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: phenyl 4,6-di-O-acetyl-2,3-di-O-benzyl-1-thio-β-D-galactopyranoside
• 英文别名: [(2R,3S,4S,5R,6S)-3-acetyloxy-4,5-bis(phenylmethoxy)-6-phenylsulfanyloxan-2-yl]methyl acetate
• CAS: 911684-18-9
• 化学式: C₃₀H₃₂O₇S
• 分子量: 536.646
• InChiKey: XHPZPPLBYSFRQP-QBHLCAJUSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5
• 重原子数：
  38
• 可旋转键数：
  13
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.33
• 拓扑面积：
  106
• 氢给体数：
  0
• 氢受体数：
  8

反应信息

• 作为反应物：
  描述：

  phenyl 4,6-di-O-acetyl-2,3-di-O-benzyl-1-thio-β-D-galactopyranoside 在 4-二甲氨基吡啶 、 三氟甲磺酸三甲基硅酯 、 camphor-10-sulfonic acid 、 sodium methylate 、 溶剂黄146 、 三乙胺 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 反应 10.0h， 生成
  参考文献：
  名称：

  Mechanistic Studies and Methods To Prevent Aglycon Transfer of Thioglycosides

  摘要：

  Thioglycosides have been employed extensively for the synthesis of complex oligosaccharides, carbohydrate libraries, and mimetics of O-glycosides. While very useful, aglycon transfer is a problematic side reaction with thioglycosides. In this paper, a series of mechanistic studies are described. The aglycon transfer process is shown to affect both armed and disarmed thioglycosides, cause anomerization of the carbon-sulfur bond of a thioglycoside, and destroy the product of a glycosylation reaction. The results indicate that the aglycon transfer process can be a major problem for a wide range of thioglycosides. This side reaction is especially important to consider when carrying out complex reactions such as solid-phase glycosylations, one-pot or orthogonal multicomponent glycosylations, and construction of carbohydrate libraries. To prevent transfer, a number of modified aglycons were examined. The 2,6-dimethylphenyl ( DMP) aglycon was found to effectively block transfer in a variety of model studies and glycosylation reactions. The DMP group can be installed in one step from a commercially available thiol ( 2,6-dimethylthiophenol) and is useable as a glycosyl donor. On the basis of these features, the DMP group is proposed as a convenient and improved aglycon for thioglycosides.

  DOI：

  10.1021/ja063247q
• 作为产物：
  描述：

  beta-D-半乳糖五乙酸酯 在 盐酸 、 4-二甲氨基吡啶 、 camphor-10-sulfonic acid 、 sodium methylate 、 四氯化锡 、 sodium hydride 、 三乙胺 作用下， 以 甲醇 、 二氯甲烷 、 N,N-二甲基甲酰胺 、 丙酮 、 乙腈 为溶剂， 反应 14.0h， 生成 phenyl 4,6-di-O-acetyl-2,3-di-O-benzyl-1-thio-β-D-galactopyranoside
  参考文献：
  名称：

  Mechanistic Studies and Methods To Prevent Aglycon Transfer of Thioglycosides

  摘要：

  Thioglycosides have been employed extensively for the synthesis of complex oligosaccharides, carbohydrate libraries, and mimetics of O-glycosides. While very useful, aglycon transfer is a problematic side reaction with thioglycosides. In this paper, a series of mechanistic studies are described. The aglycon transfer process is shown to affect both armed and disarmed thioglycosides, cause anomerization of the carbon-sulfur bond of a thioglycoside, and destroy the product of a glycosylation reaction. The results indicate that the aglycon transfer process can be a major problem for a wide range of thioglycosides. This side reaction is especially important to consider when carrying out complex reactions such as solid-phase glycosylations, one-pot or orthogonal multicomponent glycosylations, and construction of carbohydrate libraries. To prevent transfer, a number of modified aglycons were examined. The 2,6-dimethylphenyl ( DMP) aglycon was found to effectively block transfer in a variety of model studies and glycosylation reactions. The DMP group can be installed in one step from a commercially available thiol ( 2,6-dimethylthiophenol) and is useable as a glycosyl donor. On the basis of these features, the DMP group is proposed as a convenient and improved aglycon for thioglycosides.

  DOI：

  10.1021/ja063247q

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.