ethyl 3-O-benzyl-2-O-chloroacetyl-4-O-methyl-1-thio-α-L-rhamnopyranoside | 176039-84-2

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: ethyl 3-O-benzyl-2-O-chloroacetyl-4-O-methyl-1-thio-α-L-rhamnopyranoside
• CAS: 176039-84-2
• 化学式: C₁₈H₂₅ClO₅S
• 分子量: 388.913
• InChiKey: DJQSHELMKZUOCI-IHXXTUNLSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.24
• 重原子数：
  25.0
• 可旋转键数：
  8.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.61
• 拓扑面积：
  53.99
• 氢给体数：
  0.0
• 氢受体数：
  6.0

反应信息

• 作为反应物：
  描述：

  methyl 4-O-acetyl-2-O-methyl-α-L-fucopyranoside 、 ethyl 3-O-benzyl-2-O-chloroacetyl-4-O-methyl-1-thio-α-L-rhamnopyranoside 在 N-碘代丁二酰亚胺 、 三氟甲磺酸 、 4 A molecular sieve 作用下， 以 乙醚 、 1,2-二氯乙烷 为溶剂， 反应 0.25h， 以75%的产率得到methyl 4-O-acetyl-3-O-(3-O-benzyl-2-O-chloroacetyl-4-O-methyl-α-L-rhamnopyranosyl)-2-O-methyl-α-L-fucopyranoside
  参考文献：
  名称：

  Iodonium ion-assisted synthesis of a tetrameric fragment corresponding to the cell wall phenolic glycolipids of Mycobacterium kansasii serovar I

  摘要：

  Two procedures are described towards the assembly of the tyramine spacer-containing tetramer 5, a derivative of the phenolic glycolipid of Mycobacterium kansasii serovar I. First, iodonium ion-mediated glycosylation of trimeric acceptor 2a with D-rhamnopyranoside donor 10 gave fully protected tetramer 17. Selective removal of the chloroacetyl group of 17, subsequent deoxygenation and removal of the protective groups, led to target 5. The potential occurrence of double stereodifferentiation (DSD) was examined by condensation of L-fucopyranoside model acceptor 14 with both the enantiomeric rhamnopyranoside donors 10 and 13. The second procedure involves elongation of trimeric acceptor 2b with 6-deoxy-D-glucopyranoside 28. Desulfurisation of the resulting tetrameric fragment 36 followed by hydrogenation of 37 gave 38, the phenylacetyl (PhAc) of which was enzymatically removed to yield target tetramer 5.

  DOI：

  10.1016/0040-4020(96)00035-x
• 作为产物：
  描述：

  ethyl 4-O-methyl-1-thio-α-L-rhamnopyranoside 在 二正丁基氧化锡 、 碳酸氢钠 、 cesium fluoride 作用下， 以 N,N-二甲基甲酰胺 为溶剂， 反应 20.0h， 生成 ethyl 3-O-benzyl-2-O-chloroacetyl-4-O-methyl-1-thio-α-L-rhamnopyranoside
  参考文献：
  名称：

  Iodonium ion-assisted synthesis of a tetrameric fragment corresponding to the cell wall phenolic glycolipids of Mycobacterium kansasii serovar I

  摘要：

  Two procedures are described towards the assembly of the tyramine spacer-containing tetramer 5, a derivative of the phenolic glycolipid of Mycobacterium kansasii serovar I. First, iodonium ion-mediated glycosylation of trimeric acceptor 2a with D-rhamnopyranoside donor 10 gave fully protected tetramer 17. Selective removal of the chloroacetyl group of 17, subsequent deoxygenation and removal of the protective groups, led to target 5. The potential occurrence of double stereodifferentiation (DSD) was examined by condensation of L-fucopyranoside model acceptor 14 with both the enantiomeric rhamnopyranoside donors 10 and 13. The second procedure involves elongation of trimeric acceptor 2b with 6-deoxy-D-glucopyranoside 28. Desulfurisation of the resulting tetrameric fragment 36 followed by hydrogenation of 37 gave 38, the phenylacetyl (PhAc) of which was enzymatically removed to yield target tetramer 5.

  DOI：

  10.1016/0040-4020(96)00035-x