methyl 2,3,6-tri-O-benzyl-4-O-(2-O-benzyl-3,4-O-carbonyl-β-L-rhamnopyranosyl)-α-D-glucopyranoside

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl 2,3,6-tri-O-benzyl-4-O-(2-O-benzyl-3,4-O-carbonyl-β-L-rhamnopyranosyl)-α-D-glucopyranoside
• 英文别名: (3aS,4S,6R,7R,7aR)-6-[(2R,3R,4S,5R,6S)-6-methoxy-4,5-bis(phenylmethoxy)-2-(phenylmethoxymethyl)oxan-3-yl]oxy-4-methyl-7-phenylmethoxy-4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-2-one
• 化学式: C₄₂H₄₆O₁₁
• 分子量: 726.821
• InChiKey: OAAOICCEXOYQRT-RUJTVOINSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.9
• 重原子数：
  53
• 可旋转键数：
  16
• 环数：
  7.0
• sp3杂化的碳原子比例：
  0.4
• 拓扑面积：
  109
• 氢给体数：
  0
• 氢受体数：
  11

上下游信息

• 上游原料

  中文名称	英文名称	CAS号	化学式	分子量
  甲基2,3,6-三-O-苄基-ALPHA-D-吡喃葡萄糖苷	methyl O-2,3,6-tri-O-benzyl-α-D-glucopyranoside	19488-48-3	C28H32O6	464.558
  ——	phenyl 2-O-benzyl-3,4-O-carbonyl-1-thio-β-L-rhamnopyranoside	629627-27-6	C20H20O5S	372.442

反应信息

• 作为产物：
  描述：

  phenyl 2-O-benzyl-1-thio-β-L-rhamnopyranoside 在 4-二甲氨基吡啶 、 1-(苯基亚硫酰基)哌啶 、 三氟甲磺酸酐 、 2,4,6-三叔丁基嘧啶 作用下， 以 二氯甲烷 、 甲苯 为溶剂， 反应 1.83h， 生成 methyl 2,3,6-tri-O-benzyl-4-O-(2-O-benzyl-3,4-O-carbonyl-β-L-rhamnopyranosyl)-α-D-glucopyranoside
  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

• On the nitrile effect in l-rhamnopyranosylation
  作者：David Crich、Mitesh Patel

  DOI：10.1016/j.carres.2006.03.036

  日期：2006.7

  It is shown that the use of 5% acetonitrile or propionitrile in dichloromethane functions to increase the beta-selectivity of a number of L-rhamnopyranosylation reactions conducted by the thioglycoside method with activation by the 1-benzenesulfinyl piperidine/trifluoromethanesulfonic anhydride couple. The use of more significant quantities of acetonitrile or propionitrile results in the formation of complex reaction mixtures containing little coupled product, but from which Ritter-type products can be isolated. (c) 2006 Elsevier Ltd. All rights reserved.
• 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.