methyl 3,4-di-O-benzyl-6-O-pivaloyl-α-D-mannopyranoside | 173778-32-0

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl 3,4-di-O-benzyl-6-O-pivaloyl-α-D-mannopyranoside
• 英文别名: [(2R,3R,4R,5S,6S)-5-hydroxy-6-methoxy-3,4-bis(phenylmethoxy)oxan-2-yl]methyl 2,2-dimethylpropanoate
• CAS: 173778-32-0
• 化学式: C₂₆H₃₄O₇
• 分子量: 458.552
• InChiKey: FYIQUDZGMGCPBY-HUUMMWPTSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.4
• 重原子数：
  33
• 可旋转键数：
  11
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  83.4
• 氢给体数：
  1
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  2-甲氧基丙烯 、 methyl 3,4-di-O-benzyl-6-O-pivaloyl-α-D-mannopyranoside 在 溴 、 N,N-二甲基苯胺 作用下， 生成 methyl 3,4-di-O-benzyl-2-O-(1-bromo-2-methoxy-2-propyl)-6-O-pivaloyl-α-D-mannopyranoside
  参考文献：
  名称：

  Chemistry of 1-Alkoxy-1-glycosyl Radicals:  The Manno- and Rhamnopyranosyl Series. Inversion of α- to β-Pyranosides and the Fragmentation of Anomeric Radicals

  摘要：

  The formation and stereoselective quenching of 1-mannopyranosyl radicals by a tributyltin hydride-mediated intramolecular 1,5-hydrogen abstraction sequence is described. A competing process is 1,4-hydrogen atom abstraction leading principally to glucopyran-2-ulosides. Fragmentation of the anomeric radical resulting in the formation of ring opened products is a problem in certain series. The chemistry is dictated to a considerable extent by the nature of the protecting groups employed with the 4,6-benzylidene series and, for rhamnose, the Ley 3,4-dispiroketal, being particularly susceptible to the 1,4-hydrogen atom abstraction but less to the fragmentation. Photochemical conditions are described, in which these side reactions are practically eliminated, and applied to the inversion of an alpha- to a beta-mannoside in a disaccharide.

  DOI：

  10.1021/jo951194h
• 作为产物：
  描述：

  3,4,6-tri-O-acetyl-1,2-O-(1-methoxyethylidene)-β-D-mannopyranose 在 吡啶 、 2,6-二甲基吡啶 、 甲醇 、 三氟化硼乙醚 、 sodium 、 sodium hydride 、 三氟乙酸 作用下， 以 二氯甲烷 为溶剂， 反应 6.0h， 生成 methyl 3,4-di-O-benzyl-6-O-pivaloyl-α-D-mannopyranoside
  参考文献：
  名称：

  Chemistry of 1-Alkoxy-1-glycosyl Radicals:  The Manno- and Rhamnopyranosyl Series. Inversion of α- to β-Pyranosides and the Fragmentation of Anomeric Radicals

  摘要：

  The formation and stereoselective quenching of 1-mannopyranosyl radicals by a tributyltin hydride-mediated intramolecular 1,5-hydrogen abstraction sequence is described. A competing process is 1,4-hydrogen atom abstraction leading principally to glucopyran-2-ulosides. Fragmentation of the anomeric radical resulting in the formation of ring opened products is a problem in certain series. The chemistry is dictated to a considerable extent by the nature of the protecting groups employed with the 4,6-benzylidene series and, for rhamnose, the Ley 3,4-dispiroketal, being particularly susceptible to the 1,4-hydrogen atom abstraction but less to the fragmentation. Photochemical conditions are described, in which these side reactions are practically eliminated, and applied to the inversion of an alpha- to a beta-mannoside in a disaccharide.

  DOI：

  10.1021/jo951194h