methyl 2,3-di-O-acetyl-6-O-benzyl-4-iodo-α-D-galactopyranoside | 262301-21-3

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: methyl 2,3-di-O-acetyl-6-O-benzyl-4-iodo-α-D-galactopyranoside
• 英文别名: [(2S,3R,4R,5S,6R)-3-acetyloxy-5-iodo-2-methoxy-6-(phenylmethoxymethyl)oxan-4-yl] acetate
• CAS: 262301-21-3
• 化学式: C₁₈H₂₃IO₇
• 分子量: 478.281
• InChiKey: UIMSUKMPIPRCES-ICUGJSFKSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.2
• 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：
  80.3
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  methyl 2,3-di-O-acetyl-6-O-benzyl-4-iodo-α-D-galactopyranoside 在 2,6-二叔丁基-4-甲基吡啶 、 三氟甲磺酸酐 、 一水合肼 、 溶剂黄146 作用下， 以 二氯甲烷 、 N,N-二甲基甲酰胺 为溶剂， 反应 8.83h， 生成 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-glucopyranoside
  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 咪唑 、 碘 、 三苯基膦 作用下， 以 四氢呋喃 为溶剂， 以90%的产率得到methyl 2,3-di-O-acetyl-6-O-benzyl-4-iodo-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

文献信息

• Synthesis of S-linked carbohydrate analogues via a Ferrier reaction
  作者：David Ellis、Sarah E. Norman、Helen M.I. Osborn

  DOI：10.1016/j.tet.2008.01.042

  日期：2008.3

  In this work, the synthetic utility of the Ferrier reaction to access S-linked disaccharides and S-linked glycoamino acids has been probed. Significantly, entry to a range of 1,4- and 1,6-S-linked disaccharides has been achieved using glycals derived from glucose and galactose, and sulfur containing coupling partners derived from methyl alpha-D-glucopyranoside. Access to S-linked glycoamino acids and glycopeptides has also been achieved using protected cysteine and homocysteine coupling partners within the Ferrier reaction. Functionalisation of the Ferrier products, for example, via dihydroxylation using OsO4 or amino acid coupling, and deprotection of the targets have also been achieved. In this way, entry to materials of interest as mimics of biologically interesting disaccharides and glycopeptides has been realised, including targets derived from rare sugars such as talopyranose and gulopyranose. (C) 2008 Elsevier Ltd. All rights reserved.