ethyl 2,3,4,7-tetra-O-benzyl-1-thio-6-O-trimethylsilyl-L-glycero-α-D-manno-heptopyranoside | 215381-15-0

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: ethyl 2,3,4,7-tetra-O-benzyl-1-thio-6-O-trimethylsilyl-L-glycero-α-D-manno-heptopyranoside
• 英文别名: Bn(-2)[Bn(-3)][Bn(-4)][TMS(-6)][Bn(-7)]LDManHep(a)-SEt；[(1S)-1-[(2S,3S,4S,5S,6R)-6-ethylsulfanyl-3,4,5-tris(phenylmethoxy)oxan-2-yl]-2-phenylmethoxyethoxy]-trimethylsilane
• CAS: 215381-15-0
• 化学式: C₄₀H₅₀O₆SSi
• 分子量: 686.985
• InChiKey: IQFACTKDNUMQAO-MYKKKZLNSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  8.66
• 重原子数：
  48
• 可旋转键数：
  18
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.4
• 拓扑面积：
  80.7
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  ethyl 2,3,4,7-tetra-O-benzyl-1-thio-6-O-trimethylsilyl-L-glycero-α-D-manno-heptopyranoside 在 N-碘代丁二酰亚胺 、 三氟甲磺酸 作用下， 以 乙醚 、 二氯甲烷 为溶剂， 反应 0.42h， 以85%的产率得到1,6-anhydro-2,3,4,7-tetra-O-benzyl-L-glycero-β-D-manno-heptopyranose
  参考文献：
  名称：

  Synthesis of a Branched Heptose- and Kdo-Containing Common Tetrasaccharide Core Structure of Haemophilus influenzae Lipopolysaccharides via a 1,6-Anhydro-l-glycero-β-d-manno-heptopyranose Intermediate

  摘要：

  The synthesis of a common tetrasaccharide core structure of Haemophilus influenzae lipopolysaccharides, beta-D-glucopyranosyl-(1-->4)-[L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)]-L-glycero-alpha-D-manno-heptopyranosyl-(1-->5)-3-deoxy-alpha-D-manno-octulopyranoside and the trisaccharide beta-D-glucopyranosyl-(1-->4)-[L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)]-L-glycero-alpha-D-manno-heptopyranoside is described. The oligosaccharides are synthesized as glycosides of a bifunctional spacer, 2-(4-aminophenyl)ethanol, to allow the subsequent formation of immunogenic glycoconjugates, which will be evaluated as well-defined glycoconjugate vaccine candidates. The syntheses of the 3,4-branched structures were accomplished using a 1,6-anhydro-L-glycero-beta-D-manno-heptopyranose intermediate to diminish the steric crowding between the 3- and 1-substituent. This intermediate was effectively synthesized from a mannose precursor via a stereoselective one-carbon elongation using a Barbier reaction (which was found to be more convenient than a Grignard reaction) and anhydro bridge formation through an internal glycosylation of a 6-O-trimethylsilylated ethyl thioheptoside using NIS/TfOH as a promoter. The 3- and 4-substituent were readily introduced into the 1,6-anhydro intermediate by glycosylation reactions using thioglycosides as donors and NIS/TfOH as a promoter, a task which has not been possible using accepters with equatorial 3,4-substituents. Acetolysis of the anhydro bridge followed by conversion into the ethyl thioglycoside afforded a trisaccharide donor, which, in NIS/TfOH-promoted couplings to the spacer and to a Kdo acceptor followed by deprotection, efficiently gave the two target compounds.

  DOI：

  10.1021/jo9808573
• 作为产物：
  描述：

  ethyl 2,3,4-tri-O-benzyl-1,6-dialdo-1-thio-α-D-manno-pyranoside 在 吡啶 、 magnesium 、 mercury dibromide 作用下， 以 四氢呋喃 为溶剂， 反应 1.5h， 生成 ethyl 2,3,4,7-tetra-O-benzyl-1-thio-6-O-trimethylsilyl-L-glycero-α-D-manno-heptopyranoside
  参考文献：
  名称：

  Synthesis of a Branched Heptose- and Kdo-Containing Common Tetrasaccharide Core Structure of Haemophilus influenzae Lipopolysaccharides via a 1,6-Anhydro-l-glycero-β-d-manno-heptopyranose Intermediate

  摘要：

  The synthesis of a common tetrasaccharide core structure of Haemophilus influenzae lipopolysaccharides, beta-D-glucopyranosyl-(1-->4)-[L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)]-L-glycero-alpha-D-manno-heptopyranosyl-(1-->5)-3-deoxy-alpha-D-manno-octulopyranoside and the trisaccharide beta-D-glucopyranosyl-(1-->4)-[L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)]-L-glycero-alpha-D-manno-heptopyranoside is described. The oligosaccharides are synthesized as glycosides of a bifunctional spacer, 2-(4-aminophenyl)ethanol, to allow the subsequent formation of immunogenic glycoconjugates, which will be evaluated as well-defined glycoconjugate vaccine candidates. The syntheses of the 3,4-branched structures were accomplished using a 1,6-anhydro-L-glycero-beta-D-manno-heptopyranose intermediate to diminish the steric crowding between the 3- and 1-substituent. This intermediate was effectively synthesized from a mannose precursor via a stereoselective one-carbon elongation using a Barbier reaction (which was found to be more convenient than a Grignard reaction) and anhydro bridge formation through an internal glycosylation of a 6-O-trimethylsilylated ethyl thioheptoside using NIS/TfOH as a promoter. The 3- and 4-substituent were readily introduced into the 1,6-anhydro intermediate by glycosylation reactions using thioglycosides as donors and NIS/TfOH as a promoter, a task which has not been possible using accepters with equatorial 3,4-substituents. Acetolysis of the anhydro bridge followed by conversion into the ethyl thioglycoside afforded a trisaccharide donor, which, in NIS/TfOH-promoted couplings to the spacer and to a Kdo acceptor followed by deprotection, efficiently gave the two target compounds.

  DOI：

  10.1021/jo9808573

文献信息

• Synthesis of a Branched Heptose- and Kdo-Containing Common Tetrasaccharide Core Structure of <i>Haemophilus </i><i>i</i><i>nfluenzae</i> Lipopolysaccharides via a 1,6-Anhydro-<scp>l</scp>-<i>g</i><i>lycero</i>-β-<scp>d</scp>-<i>m</i><i>anno-</i>heptopyranose Intermediate
  作者：Christian Bernlind、Stefan Oscarson

  DOI：10.1021/jo9808573

  日期：1998.10.1

  The synthesis of a common tetrasaccharide core structure of Haemophilus influenzae lipopolysaccharides, beta-D-glucopyranosyl-(1-->4)-[L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)]-L-glycero-alpha-D-manno-heptopyranosyl-(1-->5)-3-deoxy-alpha-D-manno-octulopyranoside and the trisaccharide beta-D-glucopyranosyl-(1-->4)-[L-glycero-alpha-D-manno-heptopyranosyl-(1-->3)]-L-glycero-alpha-D-manno-heptopyranoside is described. The oligosaccharides are synthesized as glycosides of a bifunctional spacer, 2-(4-aminophenyl)ethanol, to allow the subsequent formation of immunogenic glycoconjugates, which will be evaluated as well-defined glycoconjugate vaccine candidates. The syntheses of the 3,4-branched structures were accomplished using a 1,6-anhydro-L-glycero-beta-D-manno-heptopyranose intermediate to diminish the steric crowding between the 3- and 1-substituent. This intermediate was effectively synthesized from a mannose precursor via a stereoselective one-carbon elongation using a Barbier reaction (which was found to be more convenient than a Grignard reaction) and anhydro bridge formation through an internal glycosylation of a 6-O-trimethylsilylated ethyl thioheptoside using NIS/TfOH as a promoter. The 3- and 4-substituent were readily introduced into the 1,6-anhydro intermediate by glycosylation reactions using thioglycosides as donors and NIS/TfOH as a promoter, a task which has not been possible using accepters with equatorial 3,4-substituents. Acetolysis of the anhydro bridge followed by conversion into the ethyl thioglycoside afforded a trisaccharide donor, which, in NIS/TfOH-promoted couplings to the spacer and to a Kdo acceptor followed by deprotection, efficiently gave the two target compounds.