(3aR,4R,6R,7S,7aS)-4-[[(2R,3R,4S,5R,6S)-6-methoxy-3,4,5-tris(phenylmethoxy)oxan-2-yl]methoxy]-7-phenylmethoxy-6-(phenylmethoxymethyl)-4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-2-one | 1380234-17-2

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (3aR,4R,6R,7S,7aS)-4-[[(2R,3R,4S,5R,6S)-6-methoxy-3,4,5-tris(phenylmethoxy)oxan-2-yl]methoxy]-7-phenylmethoxy-6-(phenylmethoxymethyl)-4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-2-one
• CAS: 1380234-17-2
• 化学式: C₄₉H₅₂O₁₂
• 分子量: 832.945
• InChiKey: SVCPEZIJNUXLFO-RJEPJANDSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.8
• 重原子数：
  61
• 可旋转键数：
  20
• 环数：
  8.0
• sp3杂化的碳原子比例：
  0.37
• 拓扑面积：
  119
• 氢给体数：
  0
• 氢受体数：
  12

反应信息

• 作为产物：
  描述：

  p-tolyl 4,6-O-benzylidene-1-thio-β-D-galactopyranoside 在 吡啶 、 吗啉,4-(苯基亚硫酰基)- 、 sodium hydride 、 2,3-二氯-5,6-二氰基-1,4-苯醌 作用下， 以 甲醇 、 二氯甲烷 、 水 、 N,N-二甲基甲酰胺 、 mineral oil 为溶剂， 反应 16.5h， 生成 (3aR,4R,6R,7S,7aS)-4-[[(2R,3R,4S,5R,6S)-6-methoxy-3,4,5-tris(phenylmethoxy)oxan-2-yl]methoxy]-7-phenylmethoxy-6-(phenylmethoxymethyl)-4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-2-one 、 methyl (4,6-di-O-benzyl-2,3-O-carbonyl-α-D-galactopyranosyl)-(1->6)-2,3,4-tri-O-benzyl-α-D-glucopyranoside
  参考文献：
  名称：

  Lewis Acids as α-Directing Additives in Glycosylations by Using 2,3-O-Carbonate-Protected Glucose and Galactose Thioglycoside Donors Based on Preactivation Protocol

  摘要：

  Catalytic or stoichiometric amounts of Lewis acids were found to be very effective a-directing additives in the stereoselective glycosylations of diverse 2,3-O-carbonate-protected glucose and galactose thioglycoside donors by preactivation protocol. The poor stereoselectivities of 4,6-di-O-acetyl-2,3-O-carbonate protected thioglycoside donors in glycosyl coupling reactions were greatly improved, and excellent alpha-stereoselectivities were achieved by the addition of 0.2 equiv of BF3 center dot OEt2. On the other hand, the beta-selectivities of 4,6-di-O-benzyl-2,3-O-carbonate-protected thioglucoside donor toward glycosylations were reversed completely to the alpha-selectivities by the use of 1 equiv of SnCl4, making the stereoselectivity controllable. Furthermore, the poor stereoselectivities of 4,6-di-O-benzyl-2,3-O-carbonate-protected thiogalactoside donor in glycosylations were also improved by using SnCl4 as additive.

  DOI：

  10.1021/jo3002084

文献信息

• Lewis Acids as α-Directing Additives in Glycosylations by Using 2,3-<i>O</i>-Carbonate-Protected Glucose and Galactose Thioglycoside Donors Based on Preactivation Protocol
  作者：Yiqun Geng、Qi Qin、Xin-Shan Ye

  DOI：10.1021/jo3002084

  日期：2012.6.15

  Catalytic or stoichiometric amounts of Lewis acids were found to be very effective a-directing additives in the stereoselective glycosylations of diverse 2,3-O-carbonate-protected glucose and galactose thioglycoside donors by preactivation protocol. The poor stereoselectivities of 4,6-di-O-acetyl-2,3-O-carbonate protected thioglycoside donors in glycosyl coupling reactions were greatly improved, and excellent alpha-stereoselectivities were achieved by the addition of 0.2 equiv of BF3 center dot OEt2. On the other hand, the beta-selectivities of 4,6-di-O-benzyl-2,3-O-carbonate-protected thioglucoside donor toward glycosylations were reversed completely to the alpha-selectivities by the use of 1 equiv of SnCl4, making the stereoselectivity controllable. Furthermore, the poor stereoselectivities of 4,6-di-O-benzyl-2,3-O-carbonate-protected thiogalactoside donor in glycosylations were also improved by using SnCl4 as additive.