methyl 2,3-di-O-benzyl-4,6-O-(benzylidene)-β-D-galactopyranoside | 162426-14-4

• 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-(benzylidene)-β-D-galactopyranoside
• 英文别名: methyl 4,6-O-benzylidene-β-D-galactopyranoside 2,3-di-O-benzoate；methyl 2,3-di-O-benzyl-4,6-O-benzylidene-β-D-glalactopyranoside；methyl 2,3-di-O-benzyl-4,6-O-benzylidene-β-D-galactopyranoside；methyl-[O²,O³-dibenzyl-O⁴,O⁶-((S)-benzylidene)-β-D-galactopyranoside]；Methyl-[O²,O³-dibenzyl-O⁴,O⁶-((S)-benzyliden)-β-D-galactopyranosid]；Methyl-2.3-di-O-benzyl-4.6-O-benzyliden-β-D-galactopyranosid
• CAS: 162426-14-4
• 化学式: C₂₈H₃₀O₆
• 分子量: 462.543
• InChiKey: CVHUOBYFXKHVJR-QZKLAINISA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4.64
• 重原子数：
  34.0
• 可旋转键数：
  8.0
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.36
• 拓扑面积：
  55.38
• 氢给体数：
  0.0
• 氢受体数：
  6.0

反应信息

• 作为反应物：
  描述：

  methyl 2,3-di-O-benzyl-4,6-O-(benzylidene)-β-D-galactopyranoside 在 水 、 苯酸四丁基铵 、 溶剂黄146 作用下， 以 乙腈 为溶剂， 生成 methyl 2,3-di-O-benzyl-6-O-benzoyl-β-D-galactopyranoside
  参考文献：
  名称：

  A green and convenient method for regioselective mono and multiple benzoylation of diols and polyols

  摘要：

  An efficient method for regioselective benzoylation of diols and polyols was developed. The benzoylation is catalyzed by only 0.2 equiv of benzoate anion in acetonitrile with the addition of a stoichiometric amount of benzoic anhydride under very mild condition, leading to high yields. Compared with all other methods, this method shows particular advantage in regioselective multiple benzoylation of polyols, and in avoiding the use of any metal-based catalysts and any amine bases, which is more environment friendly. (C) 2015 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2015.12.074
• 作为产物：
  描述：

  甲基-Β-D-吡喃半乳糖苷 在 sodium hydride 、 对甲苯磺酸 作用下， 以 N,N-二甲基甲酰胺 、 乙腈 为溶剂， 生成 methyl 2,3-di-O-benzyl-4,6-O-(benzylidene)-β-D-galactopyranoside
  参考文献：
  名称：

  A green and convenient method for regioselective mono and multiple benzoylation of diols and polyols

  摘要：

  An efficient method for regioselective benzoylation of diols and polyols was developed. The benzoylation is catalyzed by only 0.2 equiv of benzoate anion in acetonitrile with the addition of a stoichiometric amount of benzoic anhydride under very mild condition, leading to high yields. Compared with all other methods, this method shows particular advantage in regioselective multiple benzoylation of polyols, and in avoiding the use of any metal-based catalysts and any amine bases, which is more environment friendly. (C) 2015 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.tet.2015.12.074

文献信息

• Automated Quantification of Hydroxyl Reactivities: Prediction of Glycosylation Reactions
  作者：Chun‐Wei Chang、Mei‐Huei Lin、Chieh‐Kai Chan、Kuan‐Yu Su、Chia‐Hui Wu、Wei‐Chih Lo、Sarah Lam、Yu‐Ting Cheng、Pin‐Hsuan Liao、Chi‐Huey Wong、Cheng‐Chung Wang

  DOI：10.1002/anie.202013909

  日期：2021.5.25

  (Aka) to quantify the nucleophilicity of hydroxyl groups in glycosylation influenced by the steric, electronic and structural effects, providing a connection between experiments and computer algorithms. The subtle reactivity differences among the hydroxyl groups on various carbohydrate molecules can be defined by Aka, which is easily accessible by a simple and convenient automation system to assure

  糖基化反应的立体选择性和产率至关重要，但不可预测。我们已经开发了一个亲核亲核常数（Aka）数据库，用于量化受空间，电子和结构效应影响的糖基化中羟基的亲核性，从而在实验和计算机算法之间建立联系。各种碳水化合物分子上的羟基之间的细微反应性差异可以由Aka定义，Aka可以通过简单便捷的自动化系统轻松访问，以确保高重现性和准确性。通过设计的软件程序“ GlycoComputer”可以组织和处理各种具有明确反应性和启动子的糖基化供体和受体，从而无需复杂的计算过程即可预测糖基化反应。通过随机森林算法进一步验证了Aka的重要性，并通过合成Lewis A骨架测试了适用性，表明可以准确估计立体选择性和产率。
• Establishment of Guidelines for the Control of Glycosylation Reactions and Intermediates by Quantitative Assessment of Reactivity
  作者：Chun‐Wei Chang、Chia‐Hui Wu、Mei‐Huei Lin、Pin‐Hsuan Liao、Chun‐Chi Chang、Hsiao‐Han Chuang、Su‐Ching Lin、Sarah Lam、Ved Prakash Verma、Chao‐Ping Hsu、Cheng‐Chung Wang

  DOI：10.1002/anie.201906297

  日期：2019.11.18

  Stereocontrolled chemical glycosylation remains a major challenge despite vast efforts reported over many decades and so far still mainly relies on trial and error. Now it is shown that the relative reactivity value (RRV) of thioglycosides is an indicator for revealing stereoselectivities according to four types of acceptors. Mechanistic studies show that the reaction is dominated by two distinct intermediates:

  尽管数十年来进行了大量的努力，但立体控制的化学糖基化仍然是一个主要挑战，到目前为止，仍然主要依靠反复试验。现在表明，硫糖苷的相对反应性值（RRV）是根据四种受体揭示立体选择性的指标。机理研究表明，该反应由两种不同的中间体控制：糖基三氟甲磺酸酯和来自N-卤代琥珀酰亚胺（NXS）/ TfOH的糖基卤化物。糖基卤化物的形成与α-糖苷的产生高度相关。这些发现使得能够通过使用RRV作为α/β-选择性指示剂来预见糖基化反应，并且为立体控制糖基化开发了指导方针和规则。
• Reductive Openings of Benzylidene Acetals Revisited: A Mechanistic Scheme for Regio- and Stereoselectivity
  作者：Richard Johnsson、Markus Ohlin、Ulf Ellervik

  DOI：10.1021/jo101184d

  日期：2010.12.3

  stereoselectivities. The regioselectivity in these reactions is directed by the interaction between the Lewis acid and the most nucleophilic oxygen of the acetal, thus yielding a free 6-hydroxyl group. Finally, boranes such as BH3·NMe3 are activated by Lewis acid, which results in the borane being the most electrophilic species, and consequently the reaction shows inversed regioselectivity to give a free 4-hydroxyl

  尽管环状乙缩醛的区域选择性还原性开口很重要，但机械细节却很少。在本研究中4,6- O-亚苄基乙缩醛用作模型化合物，使用多种还原剂来解释区域选择性开口的机理。针对主要和次要同位素效应以及缺乏电子的底物的竞争性同位素研究用于评估立体选择性和区域选择性。我们表明存在三种截然不同的机制途径。在非极性溶剂（如甲苯）中，乙缩醛被反应性强的裸露路易斯酸活化，生成完全发展的氧碳鎓离子，然后被硼烷还原，立体选择性低。在THF中，路易斯酸的反应性通过与溶剂的络合物形成而得以缓和。因此，这些反应要慢得多，并且通过紧密的离子对进行，从而显示出高的立体选择性。这些反应中的区域选择性是由路易斯酸和乙缩醛中最亲核的氧之间的相互作用所决定的，因此产生了一个游离的6-羟基基团。最后，诸如BH之类的硼烷3 ·NMe 3被路易斯酸活化，这导致硼烷是最亲电子的物种，因此该反应显示出反转的区域选择性，从而得到游离的4-羟基。这些反
• Iodine–sodium cyanoborohydride-mediated reductive ring opening of 4,6-O-benzylidene acetals of hexopyranosides
  作者：Kaki Venkata Rao、Premanand R. Patil、Sridhar Atmakuri、K.P. Ravindranathan Kartha

  DOI：10.1016/j.carres.2010.10.013

  日期：2010.12

  A quick, efficient and convenient method for the regiospecific reductive ring opening of 4,6-O-benzylidene acetals of O-/S-alkyl/aryl glycosides of mono- and disaccharides, leading to the exclusive formation of the corresponding 6-O-benzyl ethers, using sodium cyanoborohydride in the presence of molecular iodine, is reported. It has been observed that common protecting groups such as ethers and esters

  快速，有效和方便的方法，用于单糖和二糖的O- / S-烷基/芳基糖苷的4,6-O-亚苄基缩醛的区域特异性还原开环，从而导致相应的6-O-排他性形成报道了在分子碘存在下使用氰基硼氢化钠的苄基醚。已经观察到，在所研究的条件下，常见的保护基如醚和酯具有良好的耐受性。当应用于葡糖胺衍生的亚苄基乙缩醛时，该反应被证明是不成功的。
• Nickel(II) Chloride-Mediated Regioselective Benzylation and Benzoylation of Diequatorial Vicinal Diols
  作者：Alexei V. Demchenko、Umesh B. Gangadharmath

  DOI：10.1055/s-2004-831318

  日期：——

  Ni(II)-chelates of monosaccharide vicinal diols were found to be useful intermediates in regioselective monobenzylation and monobenzoylation. It was observed that the substitution occurs exclusively at the position adjacent to the axially oriented substituent of the pyranose ring, for example, at C-2 of α-D-gluco and at C3 of β-D-galacto.

  发现单糖邻二醇的 Ni(II)-螯合物是区域选择性单苄基化和单苯甲酰化的有用中间体。观察到取代仅发生在与吡喃糖环的轴向取代基相邻的位置，例如，在α-D-葡萄糖的C-2和β-D-半乳糖的C3。