methyl 2,3-di-O-benzyl-4,6-O-methylidene-α-D-glucopyranoside | 82206-48-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡喃二恶英
• 英文名称: methyl 2,3-di-O-benzyl-4,6-O-methylidene-α-D-glucopyranoside
• 英文别名: (4aR,6S,7R,8S,8aR)-6-methoxy-7,8-bis(phenylmethoxy)-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxine
• CAS: 82206-48-2
• 化学式: C₂₂H₂₆O₆
• 分子量: 386.445
• InChiKey: BYODMCLFXIGNES-BDHVOXNPSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.4
• 重原子数：
  28
• 可旋转键数：
  7
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.45
• 拓扑面积：
  55.4
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为反应物：
  描述：

  methyl 2,3-di-O-benzyl-4,6-O-methylidene-α-D-glucopyranoside 在 palladium on activated charcoal 氢气 作用下， 以 甲醇 为溶剂， 生成 methyl 4,6-O-methylidene-α-D-glucopyranoside
  参考文献：
  名称：

  Structure and Reactions of Glycopyranoside Derived Dialdehydes

  摘要：

  Several 4- protected D-glucopyranosides were synthesized and cleaved by sodium metaperiodate. Depending on the protection pattern the resulting dialdehydes showed different types of structures. Predominantly dioxane structures of the hemiacetal or hemialdal type were obtained with preferred trans orientation of the exo oxygen groups at C-1 and C-2. The dialdehyde derived from methyl 4-O-methyl-alpha-D-glucopyranoside was treated with various C-nucleophiles. A higher reactivity of the aldehyde function at the former C-3 in comparison to C-2 and a special stability of dioxane type structures for glycol cleavage dialdehydes derived was observed.

  DOI：

  10.1002/prac.19983400305
• 作为产物：
  描述：

  甲基2,3,6-三-O-苄基-ALPHA-D-吡喃葡萄糖苷 、 MeSO2(CH2)2OCH2OAc 在 三氟甲磺酸 作用下， 生成 methyl 2,3-di-O-benzyl-4,6-O-methylidene-α-D-glucopyranoside
  参考文献：
  名称：

  The methylsulfonylethoxymethyl (Msem) as a hydroxyl protecting group in oligosaccharide synthesis

  摘要：

  The methylsulfonylethoxymethyl (Msem) is introduced as a base-labile, non-participating protecting group in carbohydrate chemistry. Conditions to introduce the Msem on primary and secondary alcohols are described. Removal of the Msem is best achieved using a catalytic amount of tetrabutylammonium fluoride (TBAF), with or without a nucleophilic scavenger. Applicability of the Msem group is illustrated in the assembly of an all 1,3-cis-linked mannotrioside. (c) 2010 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2010.06.007

文献信息

• A New and More Efficient Synthesis of Methylene Acetals
  作者：Chunbao Li、Guobiao Chu、Yanqiao Zhang、Yuqing Zhang

  DOI：10.1055/s-0029-1216992

  日期：2009.11

  A new and efficient synthesis of benzyl chlorides and methylene acetals by use of 2,4-dichloro-6-methoxy[1,3,5]triazine (MeOTCT) and dimethyl sulfoxide has been developed. Chlorides are the major products for benzyl alcohols, while methylene acetals are the major products for secondary alcohols. This procedure provides the highest yields so far for methylene acetals of steroids. A plausible mechanism

  已开发出一种新的有效的合成苄基氯和亚甲基​​乙缩醛的方法，是使用2,4-二氯-6-甲氧基[1,3,5]三嗪（MeOTCT）和二甲基亚砜。氯化物是苯甲醇的主要产品，而亚甲基缩醛是仲醇的主要产品。迄今为止，该方法为类固醇的亚甲基缩醛提供了最高的收率。在实验的基础上提出了一个合理的机制。 2,4-二氯-6-甲氧基[1,3,5]三嗪-二甲基亚砜-醇-苄基氯-亚甲基缩醛
• Hydrogenolysis of the 4,6-O-Ketals of Glucopyranosides. Configuration-Dependent High Regio- and Stereo-Selectivity of the Diastereoisomeric Acetophenone Derivatives
  作者：J Hajko、G Szabovik、J Kerekgyarto、M Kajtar、A Liptak

  DOI：10.1071/ch9960357

  日期：——

  Hydrogenolysis (reductive cleavage) of the (R) isomers of the acetophenone 4,6-O-derivatives of glucopyranosides with LiAlH4/AlCl3 gives the 4-O-(1'-phenylethyl) ethers with (R) configuration; the corresponding (S) isomers produce the respective (R) 6-O-(1'-phenylethyl ) ethers are produced. The hydrogenolysis of other 4,6-O-ketals affords O 4 ether derivatives; the two diastereoisomeric 4,6-O-s-butylidene derivatives (cyclic ketals ) give O 4-ethers with the opposite absolute configuration. The stereoselectivity of these reactions is explained by the development of a four-centre transition state. The absolute configuration of the ethers has been determined by means of circular dichroism measurements.

  用 LiAlH4/AlCl3 对葡萄糖苷的苯乙酮 4,6-O 衍生物的 (R) 异构体进行氢解（还原裂解），可得到 (R) 构型的 4-O-(1'-苯基乙基) 醚；相应的 (S) 异构体可生成相应的 (R) 6-O-(1'-苯基乙基 ) 醚。其他 4,6-O-酮的氢解反应会产生 O 4 醚衍生物；两种非对映异构的 4,6-O-亚丁基衍生物（环酮）会产生绝对构型相反的 O 4 醚。这些反应的立体选择性可通过四中心过渡态的发展来解释。醚的绝对构型是通过圆二色性测量确定的。
• A Convenient Synthesis of Carbohydrate Methylene Acetals
  作者：András Lipták、V. Anna Oláh、János Kerékgyártó

  DOI：10.1055/s-1982-29822

  日期：——
• Structure and Reactions of Glycopyranoside Derived Dialdehydes
  作者：Thorsten Heidelberg、Joachim Thiem

  DOI：10.1002/prac.19983400305

  日期：——

  Several 4- protected D-glucopyranosides were synthesized and cleaved by sodium metaperiodate. Depending on the protection pattern the resulting dialdehydes showed different types of structures. Predominantly dioxane structures of the hemiacetal or hemialdal type were obtained with preferred trans orientation of the exo oxygen groups at C-1 and C-2. The dialdehyde derived from methyl 4-O-methyl-alpha-D-glucopyranoside was treated with various C-nucleophiles. A higher reactivity of the aldehyde function at the former C-3 in comparison to C-2 and a special stability of dioxane type structures for glycol cleavage dialdehydes derived was observed.
• The methylsulfonylethoxymethyl (Msem) as a hydroxyl protecting group in oligosaccharide synthesis
  作者：Asghar Ali、Richard J.B.H.N. van den Berg、Herman S. Overkleeft、Gijsbert A. van der Marel、Jeroen D.C. Codée

  DOI：10.1016/j.tet.2010.06.007

  日期：2010.8

  The methylsulfonylethoxymethyl (Msem) is introduced as a base-labile, non-participating protecting group in carbohydrate chemistry. Conditions to introduce the Msem on primary and secondary alcohols are described. Removal of the Msem is best achieved using a catalytic amount of tetrabutylammonium fluoride (TBAF), with or without a nucleophilic scavenger. Applicability of the Msem group is illustrated in the assembly of an all 1,3-cis-linked mannotrioside. (c) 2010 Elsevier Ltd. All rights reserved.