α-tocopherol-o-quinonemethide | 335199-67-2

• 分子结构分类: 有机化合物 - 脂质和类脂质分子 - 异戊烯醇脂质
• 英文名称: α-tocopherol-o-quinonemethide
• 英文别名: (2R)-2,7,8-trimethyl-5-methylidene-2-[(4R,8R)-4,8,12-trimethyltridecyl]-3,4-dihydrochromen-6-one
• CAS: 335199-67-2
• 化学式: C₂₉H₄₈O₂
• 分子量: 428.699
• InChiKey: FRSFJEMUYOFZSC-IEOSBIPESA-N

物化性质

• 沸点：
  514.6±30.0 °C(Predicted)
• 密度：
  0.94±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  9.3
• 重原子数：
  31
• 可旋转键数：
  12
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.76
• 拓扑面积：
  26.3
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  {(E)-2-甲氧基-2-[(三甲基硅烷基)氧基]乙烯基}(三甲基)硅烷 、 α-tocopherol-o-quinonemethide 在 zinc(II) chloride 作用下， 以 乙腈 为溶剂， 生成 (R)-3-Methoxy-5,6,8-trimethyl-2-trimethylsilanyl-3-trimethylsilanyloxy-8-((4R,8R)-4,8,12-trimethyl-tridecyl)-1,2,3,8,9,10-hexahydro-pyrano[3,2-f]chromene
  参考文献：
  名称：

  Novel Tocopherol Compounds XI. Synthesis, Bromination and Oxidation Reactions of 3-(5-Tocopheryl)propionic Acid

  摘要：

  3-(5-生育酚)丙酸 (γ-生育酚-5-丙酸，13) 通过多步反应合成，其中异构-Diels-Alder反应是关键步骤，该反应涉及O-甲基-C,O-双(三甲基硅基)酮醇醚(10)与α-生育酚(5)的邻位醌烯烃。该化合物是首个5a取代的生育酚，显示出与α-生育酚非常相似的氧化行为。

  DOI：

  10.1055/s-1999-2594
• 作为产物：
  描述：

  天然维生素E 在 N-甲基吗啉氧化物 、 silver(l) oxide 作用下， 以 二氯甲烷 为溶剂， 生成 α-tocopherol-o-quinonemethide
  参考文献：
  名称：

  Stabilization and First Direct Spectroscopic Evidence of the o-Quinone Methide Derived from Vitamin E

  摘要：

  graphicThe o-quinone methide (2) derived from vitamin E (1) can be stabilized at low temperatures in a complex with the highly polar N-methylmorpholine-N-oxide (5). The lifetime of 2 can thus be prolonged from less than 10 s to several minutes. In the complex formed, 2 adopts a zwitterionic, aromatic structure with the exocyclic methylene group in perpendicular arrangement to the ring plane, stabilized by the negatively charged oxygen in 5.

  DOI：

  10.1021/ol026917f

文献信息

• Formation and Decay Dynamics of Vitamin E Radical in the Antioxidant Reaction of Vitamin E
  作者：Kazuo Mukai、Aya Ouchi、Akiko Mitarai、Keishi Ohara、Chihiro Matsuoka

  DOI：10.1246/bcsj.82.494

  日期：2009.3.15

  understand the dynamics of antioxidant actions of vitamin E (α-, β-, γ-, and δ-tocopherols, TocH) in biological systems, kinetic study of the formation and decay reactions of vitamin E radicals (α-, β-, γ-, and δ-tocopheroxyls, Toc•) has been performed in organic solvents, using stopped-flow spectrophotometry. By mixing α-, β-, γ-, and δ-TocH with aryloxyl radical (ArO•) in ethanol, the peaks of the UV-vis

  为了了解维生素 E（α-、β-、γ-和 δ-生育酚，TocH）在生物系统中的抗氧化作用动力学，对维生素 E 自由基（α-、β -、γ- 和 δ-生育酚 (Toc•) 已在有机溶剂中使用停流分光光度法进行了分析。通过将 α-、β-、γ- 和 δ-TocH 与芳氧基 (ArO•) 在乙醇中混合，α-、β-、γ- 和 δ-Toc• 自由基引起的 UV-vis 吸收峰迅速出现在ca。430-340 nm，出现最大值，然后逐渐衰减。α-Toc• 的形成和衰变（即双分子歧化）反应的二级速率常数（kf 和 2k d ）是通过将观测曲线与通过相关微分方程数值计算获得的模拟曲线进行比较来确定的。对上述反应。根据结果​​，确定了α-Toc•自由基的光谱的最大吸收波长(λ max i) 和摩尔消光系数(ei ) (i = 1-4)。已经观察到显着的溶剂效应对于 α-Toc• 自由基的反应速率（kf 和 2k d
• Rosenau, Thomas; Kosma, Paul, European Journal of Organic Chemistry, 2001, # 5, p. 947 - 956
  作者：Rosenau, Thomas、Kosma, Paul

  DOI：——

  日期：——
• Extraordinary Kinetic Behavior of the .alpha.-Tocopheroxyl (Vitamin E) Radical
  作者：Vincent W. Bowry、K. U. Ingold

  DOI：10.1021/jo00122a026

  日期：1995.9

  Rate constants which have been reported for the bimolecular self-reaction of alpha-tocopheroxyl radicals vary by about 5 orders of magnitude. We have found that the observed bimolecular rate constant can vary by about a factor of 7 during a single, but typical experiment, e.g., in chlorobenzene at 37 degrees C from ca. 7 x 10(3) M(-1) s(-1) initially to ca. 1 x 10(3) M(-1) s(-1) finally. The overall reaction involves a disproportionation with the transfer of a hydrogen atom from the 5-methyl group of one radical to the phenoxyl oxygen atom of the other radical forming alpha-tocopherol and an o-quinone methide. In the slow regime (which corresponds to the true reaction of two alpha-tocopheroxyl radicals) this disproportionation has a deuterium kinetic isotope effect of 3.7. The bizarre kinetic behavior observed with alpha-tocopheroxyl radicals has been traced to a very minor impurity which will be present in any normal sample of alpha-tocopherol. The impurity in question is a bisphenol in which two alpha-tocopherol moieties have become linked through their 5-methyl carbon atoms. This bisphenol is a ''natural'' impurity in alpha-tocopherol since it will be formed upon exposure of alpha-tocopherol to air. The coupling of two o-quinone methide molecules yields a spiro-dimer which is then reduced to the bisphenol, probably by unoxidized alpha-tocopherol.