methyl 5-acetamido-8,9-O-benzylidene-2,3-didehydro-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate | 133585-58-7

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 二恶烷
• 英文名称: methyl 5-acetamido-8,9-O-benzylidene-2,3-didehydro-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate
• CAS: 133585-58-7
• 化学式: C₁₉H₂₃NO₈
• 分子量: 393.394
• InChiKey: URZTUKOUMKAQHW-WQYJZOQMSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -0.22
• 重原子数：
  28.0
• 可旋转键数：
  5.0
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.47
• 拓扑面积：
  123.55
• 氢给体数：
  3.0
• 氢受体数：
  8.0

反应信息

• 作为反应物：
  描述：

  methyl 5-acetamido-8,9-O-benzylidene-2,3-didehydro-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate 在 氢氧化钾 、 三氯化铝 、 calcium hydride 、 硼烷-三甲胺络合物 、 4 A molecular sieve 、 四丁基碘化铵 作用下， 以 四氢呋喃 为溶剂， 反应 22.5h， 生成 methyl 5-acetamido-4,7,9-tri-O-benzyl-2,3-didehydro-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate
  参考文献：
  名称：

  Studies Directed toward the Synthesis of Polysialogangliosides: The Regio- and Stereocontrolled Synthesis of Rationally Designed Fragments of the Tetrasialoganglioside GQ_1b⁺.

  摘要：

  The synthesis of suitably protected fragments of the tetrasialoganglioside GQ1b (I), i.e., 1 (alpha-NeuAc2 -->-8-alpha-NeuAc2 --> 3-beta-Gal1 --> 4Glc), 2 (alpha-NeuAc2 --> 8-alpha-NeuAc2 --> 3Gal), 3 (GalNAc), 4 (alpha-NeuAc2 --> 8NeuAc), 5 (beta-Gal1 -->- 3GalNAc), and 42 [beta-Gal1 --> 3-beta-GalNAc1 --> 4(alpha-NeuAc2 --> 3)beta-Gal --> 4Glc], is described. All are rationally designed so that the protecting groups can be regioselectively introduced and removed, as needed, before or after the stereoselective coupling of an appropriate pair of fragments. The syntheses of 1, 2, and 4 all feature stereoselective glycosylations by glycosyl donors that bear a C-3 thiophenoxy stereocontrolling auxiliary. Compound 3 was prepared from the D-glucosamine derivative 17 by way of a novel intramolecular nucleophilic displacement with inversion of configuration. Furthermore, model glycosylations of 4-hydroxygalactose derivatives, in which the thioglycoside 3 and the fluoride 40 served as glycosyl donors, were performed. The reaction of 3 with the glycosyl acceptor 30 gave the disaccharide 31 (GalNAc-beta-1 --> 4Gal), whereas that of 40 with 41 afforded the pentasaccharide 42.

  DOI：

  10.1021/jo00032a601
• 作为产物：
  描述：

  5-(乙酰氨基)-2,6-脱水-3,5-二脱氧-D-甘油-D-乳-壬-2-烯糖酸甲酯 、 苯甲醛二甲缩醛 在 camphor-10-sulfonic acid 作用下， 以 N,N-二甲基甲酰胺 为溶剂， 反应 3.0h， 以85%的产率得到methyl 5-acetamido-8,9-O-benzylidene-2,3-didehydro-3,5-dideoxy-D-glycero-D-galacto-2-nonulopyranosonate
  参考文献：
  名称：

  Studies Directed toward the Synthesis of Polysialogangliosides: The Regio- and Stereocontrolled Synthesis of Rationally Designed Fragments of the Tetrasialoganglioside GQ_1b⁺.

  摘要：

  The synthesis of suitably protected fragments of the tetrasialoganglioside GQ1b (I), i.e., 1 (alpha-NeuAc2 -->-8-alpha-NeuAc2 --> 3-beta-Gal1 --> 4Glc), 2 (alpha-NeuAc2 --> 8-alpha-NeuAc2 --> 3Gal), 3 (GalNAc), 4 (alpha-NeuAc2 --> 8NeuAc), 5 (beta-Gal1 -->- 3GalNAc), and 42 [beta-Gal1 --> 3-beta-GalNAc1 --> 4(alpha-NeuAc2 --> 3)beta-Gal --> 4Glc], is described. All are rationally designed so that the protecting groups can be regioselectively introduced and removed, as needed, before or after the stereoselective coupling of an appropriate pair of fragments. The syntheses of 1, 2, and 4 all feature stereoselective glycosylations by glycosyl donors that bear a C-3 thiophenoxy stereocontrolling auxiliary. Compound 3 was prepared from the D-glucosamine derivative 17 by way of a novel intramolecular nucleophilic displacement with inversion of configuration. Furthermore, model glycosylations of 4-hydroxygalactose derivatives, in which the thioglycoside 3 and the fluoride 40 served as glycosyl donors, were performed. The reaction of 3 with the glycosyl acceptor 30 gave the disaccharide 31 (GalNAc-beta-1 --> 4Gal), whereas that of 40 with 41 afforded the pentasaccharide 42.

  DOI：

  10.1021/jo00032a601