methyl 2,3-di-O-acetyl-6-O-benzyl-4-thio-α-D-galactopyranoside | 262301-20-2

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: methyl 2,3-di-O-acetyl-6-O-benzyl-4-thio-α-D-galactopyranoside
• 英文别名: [(2S,3R,4R,5S,6R)-3-acetyloxy-2-methoxy-6-(phenylmethoxymethyl)-5-sulfanyloxan-4-yl] acetate
• CAS: 262301-20-2
• 化学式: C₁₈H₂₄O₇S
• 分子量: 384.45
• InChiKey: RHWPFRYYTHCYPO-DZVNLGKHSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  1.5
• 重原子数：
  26
• 可旋转键数：
  9
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.56
• 拓扑面积：
  81.3
• 氢给体数：
  1
• 氢受体数：
  8

反应信息

• 作为反应物：
  描述：

  methyl 2,3-di-O-acetyl-6-O-benzyl-4-thio-α-D-galactopyranoside 、 S-phenyl 2,3-O-benzyl-4,6-O-benzylidene-1-deoxy-1-thia-α-D-mannopyranoside S-oxide 在 2,6-二叔丁基-4-甲基吡啶 、 三氟甲磺酸酐 作用下， 以 二氯甲烷 为溶剂， 反应 2.5h， 以61%的产率得到methyl 2,3-di-O-acetyl-6-O-benzyl-4-S-(2,3-di-O-benzyl-4,6-O-benzylidene-β-D-mannopyranosyl)-4-thio-α-D-galactopyranoside
  参考文献：
  名称：

  Direct Stereoselective Synthesis of β-Thiomannosides

  摘要：

  A highly diastereoselective synthesis of beta-thiomannopyranosides is described in which S-phenyl 2,3-di-0-benzyl-4,6-O-benzylidene-1-deoxy-1-thia-alpha-D-mannopyranoside S-oxide is treated with triflic anhydride and 2,6-di-tert-butyl-4-methylpyridine in CH2Cl2 at -78 degrees C leading to the formation of an intermediate alpha-mannosyl triflate. Addition of primary, secondary, or tertiary thiols then leads to the beta-thiomannosides, by an S(N)2-like displacement, in good yield and with excellent stereoselectivity. Deprotection is achieved either by Birch reduction or by Zemplen deacetylation, of the acetyl protected aglycons, followed by hydrogenolysis over Pearlman's catalyst. The assignment of configuration of the beta-thiomannopyranosides is discussed in terms of the chemical shift of the mannose H5 resonance and the (1)J(CH) of the mannose anomeric carbon.

  DOI：

  10.1021/jo9914667
• 作为产物：
  描述：

  methyl 2,3-di-O-acetyl-6-O-benzyl-α-D-galactopyranoside 在 一水合肼 、 溶剂黄146 、 三苯基膦 、 偶氮二甲酸二乙酯 作用下， 以 四氢呋喃 、 N,N-二甲基甲酰胺 为溶剂， 反应 4.33h， 生成 methyl 2,3-di-O-acetyl-6-O-benzyl-4-thio-α-D-galactopyranoside
  参考文献：
  名称：

  Direct Stereoselective Synthesis of β-Thiomannosides

  摘要：

  A highly diastereoselective synthesis of beta-thiomannopyranosides is described in which S-phenyl 2,3-di-0-benzyl-4,6-O-benzylidene-1-deoxy-1-thia-alpha-D-mannopyranoside S-oxide is treated with triflic anhydride and 2,6-di-tert-butyl-4-methylpyridine in CH2Cl2 at -78 degrees C leading to the formation of an intermediate alpha-mannosyl triflate. Addition of primary, secondary, or tertiary thiols then leads to the beta-thiomannosides, by an S(N)2-like displacement, in good yield and with excellent stereoselectivity. Deprotection is achieved either by Birch reduction or by Zemplen deacetylation, of the acetyl protected aglycons, followed by hydrogenolysis over Pearlman's catalyst. The assignment of configuration of the beta-thiomannopyranosides is discussed in terms of the chemical shift of the mannose H5 resonance and the (1)J(CH) of the mannose anomeric carbon.

  DOI：

  10.1021/jo9914667