p-tolyl 4,6-di-O-benzyl-2,3-O-carbonyl-1-thio-β-D-galactopyranoside | 1380233-81-7

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: p-tolyl 4,6-di-O-benzyl-2,3-O-carbonyl-1-thio-β-D-galactopyranoside
• 英文别名: (3aR,4S,6R,7S,7aS)-4-(4-methylphenyl)sulfanyl-7-phenylmethoxy-6-(phenylmethoxymethyl)-4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-2-one
• CAS: 1380233-81-7
• 化学式: C₂₈H₂₈O₆S
• 分子量: 492.593
• InChiKey: MYYKGAFFOJKHJP-KQZFZZGISA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.6
• 重原子数：
  35
• 可旋转键数：
  9
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.32
• 拓扑面积：
  88.5
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  p-tolyl 4,6-di-O-benzyl-2,3-O-carbonyl-1-thio-β-D-galactopyranoside 在 吗啉,4-(苯基亚硫酰基)- 作用下， 以 二氯甲烷 为溶剂， 生成 methyl (4,6-di-O-benzyl-2,3-O-carbonyl-α-D-galactopyranosyl)-(1->3)-2,4,6-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
• 作为产物：
  描述：

  (2R,3S,4S,5R,6S)-3-(benzyloxy)-2-((benzyloxy)methyl)-4,5-bis((4-methoxybenzyl)oxy)-6-(p-tolylthio)tetrahydro-2H-pyran 在 吡啶 、 2,3-二氯-5,6-二氰基-1,4-苯醌 作用下， 以 二氯甲烷 、 水 为溶剂， 反应 1.5h， 生成 p-tolyl 4,6-di-O-benzyl-2,3-O-carbonyl-1-thio-β-D-galactopyranoside
  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