methyl 3,4-O-isopropylidene-5-C-methoxy-β-D-galactopyranoside | 218913-76-9

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 二氧吡喃
• 英文名称: methyl 3,4-O-isopropylidene-5-C-methoxy-β-D-galactopyranoside
• 英文别名: (3aR,4R,6R,7R,7aR)-4-(hydroxymethyl)-4,6-dimethoxy-2,2-dimethyl-3a,6,7,7a-tetrahydro-[1,3]dioxolo[4,5-c]pyran-7-ol
• CAS: 218913-76-9
• 化学式: C₁₁H₂₀O₇
• 分子量: 264.276
• InChiKey: GKIGYRXIRYHVAZ-UEWQFTGXSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -1.3
• 重原子数：
  18
• 可旋转键数：
  3
• 环数：
  2.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  86.6
• 氢给体数：
  2
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  methyl 3,4-O-isopropylidene-5-C-methoxy-β-D-galactopyranoside 在 sodium tetrahydroborate 、 N-甲基吲哚酮 、 molecular sieve 、 四丙基高钌酸铵 、 Amberlist 15 ion-exchange resin 、 Dowex 50 WX₂ 、 Novozym N₄₃₅ lipase 、 水 作用下， 以 甲醇 、 二氯甲烷 为溶剂， 反应 250.0h， 生成 L-ribo-hexos-5-ulose
  参考文献：
  名称：

  The First Synthesis of aRibo-Hexos-5-Ulose: the L-Enantiomer

  摘要：

  The title compound, previously unreported in either enantioform, and its 2,6-di-O-benzyl derivative have been synthesized through a stereocontrolled epimerization at C-2 of 6-O-protected methyl 3,4-O-isopropylidene-5-C-methoxy-beta-D-galactopyranosides The epimerization, performed through a high yielding sequence of oxidation-reduction owing to the cooperative role of the equatorial C-l aglycon and the steric hindrance of the isopropylidene group, turned out to be completely diastereoselective. Whereas the unprotected L-ribo-hexos-5-ulose exists, as proved by NMR in D2O, in five main tautomeric forms in a ratio of about 4:2:2:1:1, only two anomeric 1,4-furanosic forms are present at equilibrium in its 2,6-di-O-benzyl derivative, in ratios ranging from 10:1 to 7:3, depending on the prevalence of D2O or CD3CN in the solvent mixture.

  DOI：

  10.1080/07328309908544053
• 作为产物：
  描述：

  methyl 2,6-di-O-benzyl-5-C-methoxy-β-D-galactopyranoside 在 palladium dihydroxide 氢气 、 对甲苯磺酸 作用下， 以 乙酸乙酯 为溶剂， 反应 6.0h， 生成 methyl 3,4-O-isopropylidene-5-C-methoxy-β-D-galactopyranoside
  参考文献：
  名称：

  The First Synthesis of aRibo-Hexos-5-Ulose: the L-Enantiomer

  摘要：

  The title compound, previously unreported in either enantioform, and its 2,6-di-O-benzyl derivative have been synthesized through a stereocontrolled epimerization at C-2 of 6-O-protected methyl 3,4-O-isopropylidene-5-C-methoxy-beta-D-galactopyranosides The epimerization, performed through a high yielding sequence of oxidation-reduction owing to the cooperative role of the equatorial C-l aglycon and the steric hindrance of the isopropylidene group, turned out to be completely diastereoselective. Whereas the unprotected L-ribo-hexos-5-ulose exists, as proved by NMR in D2O, in five main tautomeric forms in a ratio of about 4:2:2:1:1, only two anomeric 1,4-furanosic forms are present at equilibrium in its 2,6-di-O-benzyl derivative, in ratios ranging from 10:1 to 7:3, depending on the prevalence of D2O or CD3CN in the solvent mixture.

  DOI：

  10.1080/07328309908544053

文献信息

• The acetonation of methyl 5-C-methoxy-β-d-galactopyranoside1The nomenclature for these bis-glycosides is still somewhat ambiguous, since the introduction of a substituent at C-5, according to the Cahn, Ingold, Prelog rules, may invert its absolute configuration. We have preferred to use the Fischer nomenclature, since it is simpler and directly correlated with the name of the base compound, which undergoes a substitution of a hydrogen atom with a MeO group. This nomenclature has been previously used by us and by other authors, and is reported without change in Chemical Abstract. According to the more recent rules, the name would be methyl (5R)-5-methoxy-α-l-arabino-hexopyranoside.1 with 2,2-dimethoxypropane
  作者：Maria Camilla Bergonzi、Giorgio Catelani、Felicia D’Andrea、Francesco De Rensis

  DOI：10.1016/s0008-6215(98)00211-0

  日期：1998.10

  Abstract The acetonation of methyl 5- C -methoxy- β - d -galactopyranoside ( 1a ), masked bis-glycoside form of l - arabino -hexos-5-ulose, with a large excess of 2,2-dimethoxypropane and catalytic amounts of p -toluenesulfonic acid gives a mixture of five acetonides. The most abundant isolated product was the mixed acetal methyl 6- O -(1–methoxy-1-methylethyl)-3,4- O -isopropylidene-5- C -methoxy-

  摘要甲基5-C-甲氧基-β-d-吡喃半乳糖苷（1a）的乙酰化反应，掩蔽了1-阿拉伯糖-己-5-糖的双糖苷形式，大量过量的2,2-二甲氧基丙烷和催化量的对甲苯磺酸得到五种丙酮化物的混合物。分离出的产物最多的是混合的缩醛甲基6-O-（1-甲氧基-1-甲基乙基）-3,4- O-异亚丙基-5- C-甲氧基-β-d-吡喃半乳糖苷（44％收率）。
• The First Synthesis of a<i>Ribo</i>-Hexos-5-Ulose: the L-Enantiomer
  作者：Pier Luigi Barili、Maria Camilla Bergonzi、Giancarlo Berti、Giorgio Catelani、Felicia D'Andrea、Francesco De Rensis

  DOI：10.1080/07328309908544053

  日期：1999.1

  The title compound, previously unreported in either enantioform, and its 2,6-di-O-benzyl derivative have been synthesized through a stereocontrolled epimerization at C-2 of 6-O-protected methyl 3,4-O-isopropylidene-5-C-methoxy-beta-D-galactopyranosides The epimerization, performed through a high yielding sequence of oxidation-reduction owing to the cooperative role of the equatorial C-l aglycon and the steric hindrance of the isopropylidene group, turned out to be completely diastereoselective. Whereas the unprotected L-ribo-hexos-5-ulose exists, as proved by NMR in D2O, in five main tautomeric forms in a ratio of about 4:2:2:1:1, only two anomeric 1,4-furanosic forms are present at equilibrium in its 2,6-di-O-benzyl derivative, in ratios ranging from 10:1 to 7:3, depending on the prevalence of D2O or CD3CN in the solvent mixture.