phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-α-D-mannopyranoside

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-α-D-mannopyranoside
• 英文别名: Phenyl 2-O,3-O-dibenzyl-4-O,6-O-benzylidene-1-thio-alpha-D-mannopyranoside；(4aR,6R,7S,8S,8aR)-2-phenyl-7,8-bis(phenylmethoxy)-6-phenylsulfanyl-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxine
• 化学式: C₃₃H₃₂O₅S
• 分子量: 540.68
• InChiKey: KDTRYCJSIFGZHI-FLQYFCLYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  6.3
• 重原子数：
  39
• 可旋转键数：
  9
• 环数：
  6.0
• sp3杂化的碳原子比例：
  0.27
• 拓扑面积：
  71.4
• 氢给体数：
  0
• 氢受体数：
  6

反应信息

• 作为反应物：
  描述：

  phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-α-D-mannopyranoside 在 咪唑 、 Stryker's reagent 、 四丁基氟化铵 、 水 、 sodium hydride 、 戴斯-马丁氧化剂 、 对甲苯磺酸 、 2,3-二氯-5,6-二氰基-1,4-苯醌 、 2,4,6-三叔丁基嘧啶 作用下， 以 四氢呋喃 、 甲醇 、 二氯甲烷 、 二氯甲烷-D2 、 N,N-二甲基甲酰胺 、 mineral oil 、 苯 为溶剂， 反应 109.67h， 生成 (2R,3S,4S,4aR,6S,8aR)-3,4-bis(benzyloxy)-6-phenyloctahydropyrano[3,2-b]pyran-2-yl trifluoromethanesulfonate
  参考文献：
  名称：

  Influence of O6 in Mannosylations Using Benzylidene Protected Donors: Stereoelectronic or Conformational Effects?

  摘要：

  The stereoselective synthesis of beta-mannosides and the underlying reaction mechanism have been thoroughly studied, and especially the benzylidene-protected mannosides have gained a lot of attention since the corresponding mannosyl triflates often give excellent selectivity. The hypothesis for the enhanced stereoselectivity has been that the benzylidene locks the molecule in a less reactive conformation with the O6 trans to the ring oxygen (O5), which would stabilize the formed alpha-triflate and subsequent give beta-selectivity. In this work, the hypothesis is challenged by using the carbon analogue (C7) of the benzylidene-protected mannosyl donor, which is investigated in terms of diastereoselectivity and reactivity and by low-temperature NMR In terms of diastereoselectivity, the C-7-analogue behaves similarly to the benzylidene-protected donor, but its low-temperature NMR reveals the formation of several reactive intermediate. One of the intermediates was found to be the beta-oxosulfonium ion. The reactivity of the donor was found to be in between that of the "torsional" disarmed and an armed donor.

  DOI：

  10.1021/jo302455d
• 作为产物：
  描述：

  溴甲苯 、 phenyl 4,6-O-benzylidene-1-thio-α-D-mannopyranoside 在 sodium hydride 作用下， 以 N,N-二甲基甲酰胺 为溶剂， 以98 %的产率得到phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-α-D-mannopyranoside
  参考文献：
  名称：

  使用交换 NMR 检测和表征快速平衡的糖基化反应中间体

  摘要：

  糖苷键的立体选择性引入（糖基化）是碳水化合物化学合成中的主要挑战之一。糖基化反应机理难以控制，因为在许多情况下，无法检测到驱动产物形成的确切反应性物质，并且无法通过观察到的初级反应中间体来解释产物结果。在这些情况下，预计反应将通过其他低丰度反应中间体进行，这些中间体通过 Curtin-Hammett 情景与初级反应中间体处于快速平衡状态。尽管这一原理在有机合成中广为人知，但在糖基化反应中研究该模型的机理研究由于检测导致产物形成的极短寿命反应性物质的挑战而变得复杂。在此，我们报道了低丰度反应中间体与稳定的、易于观察的 α-糖基三氟甲磺酸酯中间体之间的化学平衡的利用，以便通过采用交换 NMR 推断前一种物质的结构。使用该技术，我们能够检测反应中间体，例如 β-糖基三氟甲磺酸酯和糖基二恶阳离子。这证明了交换核磁共振在解开反应机制方面的力量，因为我们的目标是建立一个动力学参数目录，从而理解并最终预测糖基化反应。

  DOI：

  10.1021/jacs.3c08709

文献信息

• Direct chemical synthesis of β-mannopyranosides and other glycosides via glycosyl triflates
  作者：David Crich、Sanxing Sun

  DOI：10.1016/s0040-4020(98)00426-8

  日期：1998.7

  High yield, highly stereoselective methods for the synthesis of β-mannopyranosides of primary, secondary, and tertiary alcohols are presented. Activation of mannosyl sulfoxides or mannosyl thioglycosides with trifluoromethanesulfonic anhydride or benzenesulfenyl triflate, respectively, leads to the efficient formation of α-mannosyl triflates at −78 °C in dichloromethane, in the presence of 2,6-di-

  提出了伯醇，仲醇和叔醇的β-甘露吡喃糖苷合成的高产率，高立体选择性的方法。在存在2,6-二叔丁基-4-甲基吡啶。这些三氟甲磺酸酯反应，然后小号Ñ 2样与醇得到的β型甘露糖苷。为了实现高选择性，需要使用4,6- O-亚苄基保护的甘露糖，以及使用O -2和O上的非参与性保护基团-3个捐助者。进一步证明，当耐受武装和解除武装的保护基团时，硫代糖苷/苯磺酰基三氟甲磺酸酯的活化适用于葡糖苷系列。
• Stereocontrolled glycoside synthesis by activation of glycosyl sulfone donors with scandium(<scp>iii</scp>) triflate
  作者：Amandine Xolin、Romain Losa、Aicha Kaid、Cédric Tresse、Jean-Marie Beau、François-Didier Boyer、Stéphanie Norsikian

  DOI：10.1039/c7ob02792c

  日期：——

  The activation of aryl glycosyl sulfone donors has been achieved using scandium(III) triflate and has led to the selective preparation of α-mannosides resulting from a post-glycosylation anomerization.

  使用三氟甲磺酸scan （III）已经实现了芳基糖基砜供体的活化，并导致了由糖基化后的异构化反应产生的α-甘露糖苷的选择性制备。
• Stereospecific Entry to [4.5]Spiroketal Glycosides Using Alkylidenecarbene C−H Insertion
  作者：Duncan J. Wardrop、Wenming Zhang、Joseph Fritz

  DOI：10.1021/ol016975l

  日期：2002.2.1

  stereospecific preparation of [4.5]spiroketal glycosides utilizing the 1,5 C-H bond insertion of alkylidenecarbenes is described. Treatment of 2-oxopropyl beta-pyranosides A with lithium (trimethylsilyl)diazomethane in THF at -78 degrees C afforded 1,6-dioxaspiro[4,5]decenes B in good yield. Submission of the corresponding alpha-glycosides C to the same reagent gave the isomeric insertion products D in moderate

  [反应：见正文]描述了一种新的方法，该方法利用亚烷基卡宾的1,5- CH键插入来立体定向制备[4.5]螺酮糖苷。用-（三甲基甲硅烷基）重氮甲烷在-78℃下于THF中处理2-氧丙基丙基-吡喃二酮A，得到高产率的1,6-二氧杂螺[4,5]癸烯B。将相应的α-糖苷C提交给相同的试剂，以中等至高产率获得了异构体插入产物D。
• Solid-Phase Synthesis of β-Mannosides
  作者：David Crich、Mark Smith

  DOI：10.1021/ja011406u

  日期：2002.7.1

  The linkage of S-phenyl 2,3-di-O-benzyl-alpha-D-thiomannopyranoside to a cross-linked polystyrene support in the form of its 4,6-O-polystyrylborinate ester is described. The activation of this polymer-supported mannosyl donor is achieved at -60 degreesC in dichloromethane in the presence of 2,4,6-tri-tert-butylpyrimidine with the combination 1-benzenesulfinyl piperidine and trifluoromethanesulfonic anhydride. Addition of the donor alcohol at -60 degreesC followed by warming to room temperature and subsequent cleavage from the resin by gentle heating in aqueous acetone yields anomerically pure 2,3-di-O-abenZyl-beta-D-mannopyranosides in excellent yield, Successful, diastereoselective coupling is demonstrated with a range of primary, secondary, and tertiary glycosyl acceptors, including typical carbohydrates and threonine derivatives.
• Influence of O6 in Mannosylations Using Benzylidene Protected Donors: Stereoelectronic or Conformational Effects?
  作者：Tobias Gylling Frihed、Marthe T. C. Walvoort、Jeroen D. C. Codée、Gijs A. van der Marel、Mikael Bols、Christian Marcus Pedersen

  DOI：10.1021/jo302455d

  日期：2013.3.15

  The stereoselective synthesis of beta-mannosides and the underlying reaction mechanism have been thoroughly studied, and especially the benzylidene-protected mannosides have gained a lot of attention since the corresponding mannosyl triflates often give excellent selectivity. The hypothesis for the enhanced stereoselectivity has been that the benzylidene locks the molecule in a less reactive conformation with the O6 trans to the ring oxygen (O5), which would stabilize the formed alpha-triflate and subsequent give beta-selectivity. In this work, the hypothesis is challenged by using the carbon analogue (C7) of the benzylidene-protected mannosyl donor, which is investigated in terms of diastereoselectivity and reactivity and by low-temperature NMR In terms of diastereoselectivity, the C-7-analogue behaves similarly to the benzylidene-protected donor, but its low-temperature NMR reveals the formation of several reactive intermediate. One of the intermediates was found to be the beta-oxosulfonium ion. The reactivity of the donor was found to be in between that of the "torsional" disarmed and an armed donor.