phenyl 2-O-benzyl-3,4-O-(2,3-dimethoxybutane-2,3-diyl)-1-thio-β-L-rhamnopyranoside | 629627-25-4

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: phenyl 2-O-benzyl-3,4-O-(2,3-dimethoxybutane-2,3-diyl)-1-thio-β-L-rhamnopyranoside
• 英文别名: (2R,3R,4aS,5S,7R,8R,8aR)-2,3-dimethoxy-2,3,5-trimethyl-8-phenylmethoxy-7-phenylsulfanyl-5,7,8,8a-tetrahydro-4aH-pyrano[3,4-b][1,4]dioxine
• CAS: 629627-25-4
• 化学式: C₂₅H₃₂O₆S
• 分子量: 460.591
• InChiKey: JGCROGOYBCBYGT-CETHTKBZSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.1
• 重原子数：
  32
• 可旋转键数：
  7
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.52
• 拓扑面积：
  80.7
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  phenyl 2-O-benzyl-3,4-O-(2,3-dimethoxybutane-2,3-diyl)-1-thio-β-L-rhamnopyranoside 在 三氟乙酸 作用下， 以 水 为溶剂， 反应 0.67h， 以4.1 g的产率得到phenyl 2-O-benzyl-1-thio-β-L-rhamnopyranoside
  参考文献：
  名称：

  The 3,4-O-Carbonate Protecting Group as a β-Directing Group in Rhamnopyranosylation in Both Homogeneous and Heterogeneous Glycosylations As Compared to the Chameleon-like 2,3-O-Carbonates

  摘要：

  It is demonstrated that the beta-selectivity observed in the insoluble silver salt mediated couplings of 2,3-O-carbonate-protected rhamnosyl bromides is uniquely due to the heterogeneous nature of the reaction. In homogeneous solution these same donors are alpha-selective, a fact that is attributed to the half-chair conformation of these substances which reduces the energy barrier to oxacarbenium ion formation. It is suggested that the 2,3-O-carbonate group be dubbed torsionally arming in the manno- and rhamnopyranose series. When the carbonate group is removed to the 3,4-O-position a beta-selective system is formed, in both homogeneous and heterogeneous conditions, and it is demonstrated that this selectivity arises from the combination of the electron-withdrawing nature of the carbonate and its inability to take part in neighboring participation.

  DOI：

  10.1021/jo035003j
• 作为产物：
  描述：

  phenyl 1-thio-β-L-rhamnopyranoside 在 camphor-10-sulfonic acid 、 sodium hydride 作用下， 以 四氢呋喃 、 甲醇 为溶剂， 反应 8.0h， 生成 phenyl 2-O-benzyl-3,4-O-(2,3-dimethoxybutane-2,3-diyl)-1-thio-β-L-rhamnopyranoside
  参考文献：
  名称：

  The 3,4-O-Carbonate Protecting Group as a β-Directing Group in Rhamnopyranosylation in Both Homogeneous and Heterogeneous Glycosylations As Compared to the Chameleon-like 2,3-O-Carbonates

  摘要：

  It is demonstrated that the beta-selectivity observed in the insoluble silver salt mediated couplings of 2,3-O-carbonate-protected rhamnosyl bromides is uniquely due to the heterogeneous nature of the reaction. In homogeneous solution these same donors are alpha-selective, a fact that is attributed to the half-chair conformation of these substances which reduces the energy barrier to oxacarbenium ion formation. It is suggested that the 2,3-O-carbonate group be dubbed torsionally arming in the manno- and rhamnopyranose series. When the carbonate group is removed to the 3,4-O-position a beta-selective system is formed, in both homogeneous and heterogeneous conditions, and it is demonstrated that this selectivity arises from the combination of the electron-withdrawing nature of the carbonate and its inability to take part in neighboring participation.

  DOI：

  10.1021/jo035003j

文献信息

• The 3,4-<i>O</i>-Carbonate Protecting Group as a β-Directing Group in Rhamnopyranosylation in Both Homogeneous and Heterogeneous Glycosylations As Compared to the Chameleon-like 2,3-<i>O</i>-Carbonates
  作者：David Crich、A. U. Vinod、John Picione

  DOI：10.1021/jo035003j

  日期：2003.10.1

  It is demonstrated that the beta-selectivity observed in the insoluble silver salt mediated couplings of 2,3-O-carbonate-protected rhamnosyl bromides is uniquely due to the heterogeneous nature of the reaction. In homogeneous solution these same donors are alpha-selective, a fact that is attributed to the half-chair conformation of these substances which reduces the energy barrier to oxacarbenium ion formation. It is suggested that the 2,3-O-carbonate group be dubbed torsionally arming in the manno- and rhamnopyranose series. When the carbonate group is removed to the 3,4-O-position a beta-selective system is formed, in both homogeneous and heterogeneous conditions, and it is demonstrated that this selectivity arises from the combination of the electron-withdrawing nature of the carbonate and its inability to take part in neighboring participation.