(E)-phenylthio 2,3-di-O-benzyl-4-O-pivaloyl-6,7-dideoxy-8-C-phenyl-α-D-manno-oct-6-eno-8-ulo-pyranoside | 1421832-65-6

• 分子结构分类: 有机化合物 - 有机氧化合物
• 英文名称: (E)-phenylthio 2,3-di-O-benzyl-4-O-pivaloyl-6,7-dideoxy-8-C-phenyl-α-D-manno-oct-6-eno-8-ulo-pyranoside
• 英文别名: [(2R,3R,4S,5S,6R)-2-[(E)-3-oxo-3-phenylprop-1-enyl]-4,5-bis(phenylmethoxy)-6-phenylsulfanyloxan-3-yl] 2,2-dimethylpropanoate
• CAS: 1421832-65-6
• 化学式: C₃₉H₄₀O₆S
• 分子量: 636.809
• InChiKey: SDGICDRMSNSDCQ-WPYLFUFTSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  8.1
• 重原子数：
  46
• 可旋转键数：
  14
• 环数：
  5.0
• sp3杂化的碳原子比例：
  0.28
• 拓扑面积：
  96.4
• 氢给体数：
  0
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  (E)-phenylthio 2,3-di-O-benzyl-4-O-pivaloyl-6,7-dideoxy-8-C-phenyl-α-D-manno-oct-6-eno-8-ulo-pyranoside 在 Stryker's reagent 、 水 作用下， 以 苯 为溶剂， 反应 0.5h， 以86%的产率得到phenylthio 2,3-di-O-benzyl-4-O-pivaloyl-6,7-dideoxy-8-C-phenyl-α-D-manno-oct-8-ulopyranoside
  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：

  S-phenyl 2,3-di-O-benzyl-α-D-thiomannopyranoside 在 吡啶 、 4-二甲氨基吡啶 、 戴斯-马丁氧化剂 、 三氟乙酸 、 三氟乙酸酐 作用下， 以 二氯甲烷 为溶剂， 反应 73.5h， 生成 (E)-phenylthio 2,3-di-O-benzyl-4-O-pivaloyl-6,7-dideoxy-8-C-phenyl-α-D-manno-oct-6-eno-8-ulo-pyranoside
  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