2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl-(1→3)-methyl-2-O-benzyl-α-D-glucopyranosyl-4,6-benzylidene acetal

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: 2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl-(1→3)-methyl-2-O-benzyl-α-D-glucopyranosyl-4,6-benzylidene acetal
• 英文别名: methyl 4,6-O-benzylidene-3-O-(2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl)-α-D-glucopyranoside；(2R,4aR,6S,7R,8R,8aR)-6-methoxy-2-phenyl-8-[(2S,3R,4S,5R,6R)-3,4,5-tris(phenylmethoxy)-6-(phenylmethoxymethyl)oxan-2-yl]oxy-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxin-7-ol
• 化学式: C₄₈H₅₂O₁₁
• 分子量: 804.934
• InChiKey: QDQFTFVPVMLVAJ-AMBRVHPWSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  5.8
• 重原子数：
  59
• 可旋转键数：
  17
• 环数：
  8.0
• sp3杂化的碳原子比例：
  0.38
• 拓扑面积：
  113
• 氢给体数：
  1
• 氢受体数：
  11

反应信息

• 作为产物：
  描述：

  alpha-甲基葡萄糖甙 在 四甲基乙二胺 、 三氟甲磺酸三甲基硅酯 、 4 A molecular sieve 、 tetrathiomolybdate(VI) 、 对甲苯磺酸 作用下， 以 二氯甲烷 、 N,N-二甲基甲酰胺 、 乙腈 为溶剂， 反应 3.0h， 生成 2,3,4,6-tetra-O-benzyl-β-D-glucopyranosyl-(1→3)-methyl-2-O-benzyl-α-D-glucopyranosyl-4,6-benzylidene acetal
  参考文献：
  名称：

  炔丙氧基羰基（Poc）作为碳水化合物合成中羟基功能的保护基。

  摘要：

  [反应：参见文本]炔丙氧基羰基（Poc）可用于选择性保护碳水化合物中的羟基功能，并可在中性条件下使用CH（3）中的四硫代钼酸盐MoS（4）（2-）（1）除去CN在室温下。在去保护的条件下，苄基乙缩醛，苄基醚，乙酰基和乙酰丙酸酯，以及烯丙基碳酸酯和碳酸苄酯保持不变。还已经表明，新的保护基团（Poc）与酸性，碱性以及糖基化条件相容。

  DOI：

  10.1021/ol027220x

文献信息

• Glycosylidene Carbenes. Part 14. Glycosidation of partially protected galactopyranose-, glucopyranose-, and mannopyranose-derived vicinal diols
  作者：Pulla Reddy Muddasani、Eva Bozó、Bruno Bernet、Andrea Vasella

  DOI：10.1002/hlca.19940770128

  日期：1994.2.9

  respectively (Scheme 1, Table 3). The disaccharides derived from 4, 5, and 7 were characterized as their acetates 18/19/22/23, 26/27/30/31, and 38/39/42/43, respectively. Glycosidation of the galacto-configurated diequatorial 2,3-diols 8 and 9 and the manno-configurated diequatorial 3,4-diol 10 by 1 (Scheme 2, Table 3) also proceeded in fair yields to give the disaccharides 44–47 (69–80%;1,2-/1,3-linked products

  考察了在赤道反式-1，2和轴向赤道顺式1，2-二醇中的H键与二嗪1的糖基化的区域选择性之间的关系。根据FT-IR和1 H-NMR光谱分配H键（图1）。苷化由1所述的葡糖-构型diequatorial反式-2,3-二醇4-7，得到单-葡糖产品16/17/20/21（69-89％）; 1,2- / 1,3-链接产品（37-46：63-54），24 /25/28/ 29（60-63％； 1,2- / 1,3-链接产品46-51：54 –49），32–35（69-94％； 1,2- / 1,3-链接的产品45-52：55-48）和36/37/40/41（59-63％； 1,2- / 1,3-链接的产品产品52–59：48–41）（方案1，表3）。衍生自4、5和7的二糖的特征分别是其乙酸盐18/19/22 / 23、26 / 27/30/31和38/39/42/43。所述的糖苷化半乳-构型diequatorial
• Reciprocal donor acceptor selectivity (RDAS): A new concept for "matching" donors with acceptors
  作者：Bert Fraser-Reid、J Cristobal Lopez、K V Radhakrishnan、Mateusz Mach、Urs Schlueter、Ana Gomez、Clara Uriel

  DOI：10.1139/v02-137

  日期：2002.8.1

  Lemieux's extensive work on replacement reactions at the anomeric center helped to establish the fact that the O-2-protecting group of a donor exerts powerful control over stereoselectivity in glycoside coupling reactions. This manuscript shows that the O-2-protecting group of a donor also exerts powerful, indeed sometimes total, control over regioselectivity in glycosidation of diols. The latter acceptors also exhibit preferences over the donor, thereby providing evidence for the concept of reciprocal donor acceptor selectivity (RDAS). The latter concept is put to the test by simultaneously presenting an acceptor diol with equivalent amounts of two donors, in the hope of achieving double differential glycosidation leading to one-pot assembly of a trisaccharide. When the pair of donors did not conform to RDAS principles the reaction did not proceed beyond a dissacharide. However, when the pair was RDAS sanctioned, a single trisaccharide (out of four possibilities) was obtained.Key words: regiocontrolled glycosidation, armed and disarmed donors, di- and trioxolenium ions, oxocarbenium ion.

  Lemieux在异构中心的替代反应方面的广泛研究有助于确立这样一个事实：供体的O-2保护基在糖苷偶联反应中对立体选择性具有强大的控制作用。本文表明，供体的O-2保护基对二醇的糖苷化反应的位置选择性也具有强大的、有时甚至是完全的控制作用。后一种受体对供体也表现出偏好，从而为相互供体受体选择性（RDAS）概念提供了证据。后一概念通过同时将一个受体二醇与等量的两个供体呈现，希望实现双重差异糖苷化，从而实现三糖的一锅法组装。当这对供体不符合RDAS原则时，反应无法超过二糖。然而，当这对供体符合RDAS原则时，获得了一个单一的三糖（四种可能性中的一种）。关键词：位置控制的糖苷化，武装和非武装供体，二和三氧杂环丙阳离子，羰基离子。
• O-Glycoside Synthesis with Glycosyl Iodides under Neutral Conditions in 1 M LiClO4 in CH2Cl2
  作者：Uschi Schmid、Herbert Waldmann

  DOI：10.1002/jlac.199719971223

  日期：1997.12

  Glycosyl phosphates, imidates, trifluoroacetates, chlorides, and bromides are converted into the respective glycosyl iodides by treatment with LiI or NaI in 1 M solutions of LiClO4 in CH2Cl2. Under these neutral conditions the reactive glycosyl iodides are activated, and react with different glycosyl acceptors to give O-glycosides in moderate yields, with the α-anomers predominating. The glycosylation

  通过在1 M LiClO 4的CH 2 Cl 2溶液中用LiI或NaI处理，将糖基磷酸酯，酰亚胺基，三氟乙酸基酯，氯化物和溴化物转化为相应的糖基碘化物。在这些中性条件下，反应性糖基碘被活化，并与不同的糖基受体反应，以中等收率得到O-糖苷，其中α-端基异构体占主导。糖基化反应很可能通过从α构型的前体开始形成β构型的糖基碘化物，以及随后从轴向方向在糖基碘上攻击糖基受体而进行。
• Combined Lewis acid and Brønsted acid-mediated reactivity of glycosyl trichloroacetimidate donors
  作者：Nathan D. Gould、C. Liana Allen、Brandon C. Nam、Alanna Schepartz、Scott J. Miller

  DOI：10.1016/j.carres.2013.09.011

  日期：2013.12

  Biomimetic conditions for a synthetic glycosylation reaction, inspired by the highly conserved functionality of carbohydrate active enzymes, were explored. At the outset, we sought to generate proof of principle for this approach to developing catalytic systems for glycosylation. However, control reactions and subsequent kinetic studies showed that a stoichiometric, irreversible reaction of the catalyst and glycosyl donor was occurring, with a remarkable rate variance depending upon the structure of the carboxylic acid. It was subsequently found that a combination of Bronsted acid (carboxylic acid) and Lewis acid (MgBr2) was unique in catalyzing the desired glycosylation reaction. Thus, it was concluded that the two acids act synergistically to catalyze the desired transformation. The role of the catalytic components was tested with a number of control reactions and based on these studies a mechanism is proposed herein. (C) 2013 Elsevier Ltd. All rights reserved.
• Unexpected Role of O-2 “Protecting” Groups of Glycosyl Donors in Mediating Regioselective Glycosidation
  作者：Bert Fraser-Reid、J. Cristobal Lopez、K. V. Radhakrishnan、Mateusz Mach、Urs Schlueter、Ana M. Gomez、Clara Uriel

  DOI：10.1021/ja012383m

  日期：2002.4.1

  Glycosidation of several vicinal diols reveals that exquisite regioselectivity can be achieved by using 2-O-benzoyl n-pentenyl glycoside donors and/or their cyclic 1,2-ortho ester counterparts. The regioselective preferences for both are the same, although ratios and yields may differ. In stark contrast, glycosidation of the diols with the corresponding 2-O-benzylated donors gives poor, if any, regioselectivity.