methyl 2,3-di-O-benzyl-4,6-O-(2,3,4-tri-O-benzyl-L-rhamnopyranosylidene)-α-D-galactopyranoside | 313640-18-5

• 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-benzyl-4,6-O-(2,3,4-tri-O-benzyl-L-rhamnopyranosylidene)-α-D-galactopyranoside
• 英文别名: (2S,3'R,4'R,4aR,5'S,6S,6'S,7R,8S,8aS)-6-methoxy-6'-methyl-3',4',5',7,8-pentakis(phenylmethoxy)spiro[4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxine-2,2'-oxane]
• CAS: 313640-18-5
• 化学式: C₄₈H₅₂O₁₀
• 分子量: 788.935
• InChiKey: SELNNOQRSPNSES-CMHCWASUSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.7
• 重原子数：
  58
• 可旋转键数：
  16
• 环数：
  8.0
• sp3杂化的碳原子比例：
  0.38
• 拓扑面积：
  92.3
• 氢给体数：
  0
• 氢受体数：
  10

反应信息

• 作为反应物：
  描述：

  methyl 2,3-di-O-benzyl-4,6-O-(2,3,4-tri-O-benzyl-L-rhamnopyranosylidene)-α-D-galactopyranoside 在 lithium aluminium tetrahydride 、 三氯化铝 作用下， 以 乙醚 、 二氯甲烷 为溶剂， 反应 1.0h， 以99%的产率得到methyl 2,3-di-O-benzyl-4-O-(2,3,4-tri-O-benzyl-β-L-rhamnopyranosyl)-α-D-galactopyranoside
  参考文献：
  名称：

  通过对环状糖原酸酯的还原性切割，β-糖基键具有高度立体选择性。

  摘要：

  在该报告中描述了通过螺糖原酸酯的还原裂解制备β-糖苷。该程序基于与其他糖基化方法完全不同的概念。LiAlH（4）/ AlCl（3）还原了分子中通常具有全氢螺[2H-吡喃-2,2'-吡喃并[3,2-d] [1,3]二恶英]环系统的十二个糖原酸酯或NaCNBH（3）/ AlCl（3）。在这些原酸酯中，由D-糖内酯（1-4）和2、3-二-O-苄基-α-D-吡喃葡萄糖苷（7）制得的那些（9a-12a）或由（19a，20a）制得的那些。由L-糖内酯（5、6）和2,3-二-O-苄基-α-D-吡喃半乳糖苷（8）选择性地转化为β-（1-> 4）-糖苷（9b-12b或19b，20b）通过处理LiAlH（4）/ AlCl（3）具有极好的收率。相反，原酸酯（13a-16a或17a，用NaBH（3）CN / AlCl（3）有效还原D-糖内酯和8糖或L-糖内酯和7的组合制备的18a），得到β-（1-> 6） -糖苷

  DOI：

  10.1021/jo0005870
• 作为产物：
  描述：

  2,3,4-三-O-苄基-L-吡喃鼠李糖 在 甲氧基三甲基硅烷 、 三氟甲磺酸三甲基硅酯 、 二甲基亚砜 作用下， 以 乙酸酐 、 甲苯 为溶剂， 反应 1.5h， 生成 methyl 2,3-di-O-benzyl-4,6-O-(2,3,4-tri-O-benzyl-L-rhamnopyranosylidene)-α-D-galactopyranoside
  参考文献：
  名称：

  Synthesis and Structure of 4-O,6-O-Glycosylidene Glycosides

  摘要：

  Interglycosidic spiro ortho esters (9-20) were efficiently prepared from methyl 2,6-di-O-benzylgluco-or galactopyranoside and various sugar lactones in the presence of methoxytrimethylsilane and a catalytic amount of trimethylsilyl triflate; All of the prepared sugar ortho esters possess perhydrospiro[2H-pyran-2,2'-pyrano[3,2-d] [1,3]dioxin] ring systems commonly in their molecules and, remarkably, were afforded as single isomers. The configurations of the spiro centers in their molecules were determined or estimated by X-ray single crystallographic analysis and molecular modeling studies. By comparing the conformations of prepared ortho esters, we revealed that the difference in the stability between two possible isomers was principally caused from that between the spiro ring systems in their molecules in each case.

  DOI：

  10.1021/jo0005868

文献信息

• Synthesis and Structure of 4-<i>O</i>,6-<i>O</i>-Glycosylidene Glycosides
  作者：Hiro Ohtake、Naoto Ichiba、Moto Shiro、Shiro Ikegami

  DOI：10.1021/jo0005868

  日期：2000.12.1

  Interglycosidic spiro ortho esters (9-20) were efficiently prepared from methyl 2,6-di-O-benzylgluco-or galactopyranoside and various sugar lactones in the presence of methoxytrimethylsilane and a catalytic amount of trimethylsilyl triflate; All of the prepared sugar ortho esters possess perhydrospiro[2H-pyran-2,2'-pyrano[3,2-d] [1,3]dioxin] ring systems commonly in their molecules and, remarkably, were afforded as single isomers. The configurations of the spiro centers in their molecules were determined or estimated by X-ray single crystallographic analysis and molecular modeling studies. By comparing the conformations of prepared ortho esters, we revealed that the difference in the stability between two possible isomers was principally caused from that between the spiro ring systems in their molecules in each case.
• A Highly Stereoselective Construction of β-Glycosyl Linkages by Reductive Cleavage of Cyclic Sugar Ortho Esters
  作者：Hiro Ohtake、Naoto Ichiba、Shiro Ikegami

  DOI：10.1021/jo0005870

  日期：2000.12.1

  The preparation of beta-glycosides by the reductive cleavage of spiro sugar ortho esters is described in this report. This procedure is based on a concept completely different from those of other methods for glycosylation. Twelve sugar ortho esters that commonly possess perhydrospiro[2H-pyran-2,2'-pyrano[3,2-d][1,3]dioxin] ring systems in their molecules were reduced by LiAlH(4)/AlCl(3) or NaCNBH(3)/AlCl(3)

  在该报告中描述了通过螺糖原酸酯的还原裂解制备β-糖苷。该程序基于与其他糖基化方法完全不同的概念。LiAlH（4）/ AlCl（3）还原了分子中通常具有全氢螺[2H-吡喃-2,2'-吡喃并[3,2-d] [1,3]二恶英]环系统的十二个糖原酸酯或NaCNBH（3）/ AlCl（3）。在这些原酸酯中，由D-糖内酯（1-4）和2、3-二-O-苄基-α-D-吡喃葡萄糖苷（7）制得的那些（9a-12a）或由（19a，20a）制得的那些。由L-糖内酯（5、6）和2,3-二-O-苄基-α-D-吡喃半乳糖苷（8）选择性地转化为β-（1-> 4）-糖苷（9b-12b或19b，20b）通过处理LiAlH（4）/ AlCl（3）具有极好的收率。相反，原酸酯（13a-16a或17a，用NaBH（3）CN / AlCl（3）有效还原D-糖内酯和8糖或L-糖内酯和7的组合制备的18a），得到β-（1-> 6） -糖苷