trolox c radical | 105868-72-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 苯并吡喃
• 英文名称: trolox c radical
• 英文别名: trolox radical
• CAS: 105868-72-2
• 化学式: C₁₄H₁₇O₄
• 分子量: 249.287
• InChiKey: YUVLYDMRYVSVTE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  2.8
• 重原子数：
  18
• 可旋转键数：
  1
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  47.5
• 氢给体数：
  1
• 氢受体数：
  3

反应信息

• 作为反应物：
  描述：

  trolox c radical 在 potassium bromide 、 一氧化二氮 作用下， 以 水 为溶剂， 生成 4,5-Dihydro-3,6,8,9-tetramethyl-2H-3,9a-epoxy-1-benzoxepin-2,7-(3H)-dione
  参考文献：
  名称：

  trolox c（一种生育酚类似物）在水溶液中的氧化和反应。脉冲辐射研究

  摘要：

  Trolox c, 3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carb acid, 1，一种水溶性的 {α}-tocopherol 类似物，被氧化Br{sub 2}{sup {minus}} 得到苯氧基自由基 2。这些自由基通过二阶、pH 依赖性过程歧化得到 1 和不稳定的中间体 3，鉴定为 4,5-二氢-3， 6,8,9-四甲基-2H-3,9a-epoxy-1-benzoxepin-2,7(3H)-dione，在 235 nm 处有很强的紫外吸收。歧化速率常数随着 pH 值的增加而降低，最大的变化发生在 pH 值 2 和 9 之间，在那里它降低了 10{sup 4}。速率常数与 pH 值关系图与涉及质子化和非质子化形式 2 的三个反应的方案一致。中间体 3 经历缓慢的 pH 依赖性分解为 2-羟基-2-甲基-4-(2

  DOI：

  10.1021/ja00191a031
• 作为产物：
  描述：

  奎诺二甲基丙烯酸酯 在 potassium bromide 、 一氧化二氮 作用下， 以 水 为溶剂， 生成 trolox c radical
  参考文献：
  名称：

  trolox c（一种生育酚类似物）在水溶液中的氧化和反应。脉冲辐射研究

  摘要：

  Trolox c, 3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-carb acid, 1，一种水溶性的 {α}-tocopherol 类似物，被氧化Br{sub 2}{sup {minus}} 得到苯氧基自由基 2。这些自由基通过二阶、pH 依赖性过程歧化得到 1 和不稳定的中间体 3，鉴定为 4,5-二氢-3， 6,8,9-四甲基-2H-3,9a-epoxy-1-benzoxepin-2,7(3H)-dione，在 235 nm 处有很强的紫外吸收。歧化速率常数随着 pH 值的增加而降低，最大的变化发生在 pH 值 2 和 9 之间，在那里它降低了 10{sup 4}。速率常数与 pH 值关系图与涉及质子化和非质子化形式 2 的三个反应的方案一致。中间体 3 经历缓慢的 pH 依赖性分解为 2-羟基-2-甲基-4-(2

  DOI：

  10.1021/ja00191a031
• 作为试剂：
  描述：

  抗坏血酸 在 trolox c radical 作用下， 以 水 为溶剂， 生成 ascorbyl radical
  参考文献：
  名称：

  使用Marcus交叉关系预测有机氢原子的传输速率常数。

  摘要：

  从抗氧化剂到工业和金属酶的催化作用，涉及净氢原子转移（HAT）的化学反应在化学和生物学中无处不在。该报告开发并验证了一种程序，可以预测各种介质中羟基自由基（RO（*））的HAT反应的速率常数。我们的过程使用了Marcus交叉关系（CR），并包括对溶剂氢键对反应动力学和热力学的影响的调整。通过使用Ingold模型包括了动力学溶剂效应（KSE），并使用由Abraham开发的经验模型解释了热力学溶剂效应。这些调整对于我们称为CR / KSE模型的组合模型的成功至关重要。作为CR / KSE模型的初始测试，我们测量了2,4,6-三叔丁基苯氧基自由基与羟胺2,2'-6,6'的反应在不同溶剂中的自交换和交叉速率常数-四甲基哌啶-1-醇。在计算出的交叉速率常数和直接确定的交叉速率常数之间观察到极好的一致性。然后，我们将模型扩展到具有OH或CH键的30多个已知的HAT自由基反应，包括抗坏血酸酯，过氧自由基和α-生育酚的生物学相关反应。CR

  DOI：

  10.1073/pnas.0910347107

文献信息

• Flavonoids as Antioxidants
  作者：Slobodan V. Jovanovic、Steen Steenken、Mihajlo Tosic、Budimir Marjanovic、Michael G. Simic

  DOI：10.1021/ja00090a032

  日期：1994.6

  Spectral, acid-base, and redox properties of the phenoxyl radicals derived from 3,4-dihydroxybenzene derivatives and selected flavonoids were studied by pulse radiolysis of aqueous solutions. From the pH-dependent changes in the phenoxyl spectra, the dissociation constants were derived. The pK(a), values for the deprotonation of the 3'-OH group in the catechin (pK(a) = 4.6) and rutin (pK(a) = 4.3) radicals are similar to the pK(a) value of the 3,4-dihydroxybenzoate radicals, pK(a) = 4.2, which is expected from their similar electronic structures. Deprotonation of 5- and 7-OH in the catechin and rutin and of 5-OH in the hesperidin radicals has no effect on the radical spectra, which is explained by the inefficient coupling of the A-ring of the flavonoid radicals with the unpaired electron. Because of favorable reduction potentials of the phenoxyl radicals, E(7) = 0.56-0.7 V vs NHE, flavonoids may act as efficient antioxidants of alkylperoxyl and superoxide/hydroperoxyl radicals. The ac kinetic conductivity method was developed for the measurements of the low reaction rate constants of the superoxide radical reactions with flavonoids and phenols in aqueous solutions at pH 10. The rates of the superoxide radical reactions with flavonoids, k = 3 X 10(2)-5.1 X 10(4) M(-1) s(-1), depend on the redox properties and the charge of the flavonoids. The highest rates are measured for the oxidation of quercetin and rutin, whereas the lowest are those for the B-ring monosubstituted derivatives, with substantially higher redox potentials. Uncharged catechin at pH 7 reacts at k = 6.6 X 10(4) M(-1) s(-1), whereas the rate at pH 10, where catechin is doubly negatively charged, is approximately 4 times lower, k = 1.8 x 10(4) M(-1) s(-1). The activation parameters of the oxidation of rutin and trolox at pH 10 and methyl gallate at pH 7 were determined in an attempt to understand why the rates of the superoxide reactions are low despite high driving forces of Delta E greater than or equal to 0.4 V. Low activation enthalpies, Delta H-double dagger = 2.3-3.6 kcal/mol, and negative activation entropies, Delta S-double dagger = -25-28 cal/(mol K), point to an inner-sphere electron-transfer mechanism.
• One-electron redox potentials of phenols. Hydroxy- and aminophenols and related compounds of biological interest
  作者：S. Steenken、P. Neta

  DOI：10.1021/j100215a033

  日期：1982.9
• Antioxidant activity of phenols related to vitamin E. Are there chain-breaking antioxidants better than .alpha.-tocopherol?
  作者：Graham W. Burton、Lise Hughes、Keith U. Ingold

  DOI：10.1021/ja00356a057

  日期：1983.9
• Free radical combination reactions involving phenoxyl radicals
  作者：M. Jonsson、J. Lind、T. Reitberger、T. E. Eriksen、G. Merenyi

  DOI：10.1021/j100133a018

  日期：1993.8

  The rates of phenoxyl radical reactions with the superoxide anion radical, O2.-, a peroxyl radical, HOC(CH3)2CH2OO., and an alkyl radical, HOC(CH3)2CH2., in aqueous solution have been measured for 15 different phenoxyl radicals by means of pulse radiolysis. In addition, the one-electron reduction potentials of 10 phenoxyl radicals have been determined. The fraction of electron transfer in the reaction of phenoxyl radicals with O2.-was determined by analysis of gamma-irradiated samples. The experimental data can be accommodated by the Marcus theory for electron transfer, with the reorganization energy lambda-degrees = 155 kJ/mol for the reaction between O2.- and phenoxyl radicals.
• Rate constants for reactions of iodine atoms in solution
  作者：Z. B. Alfassi、R. E. Huie、S. Marguet、E. Natarajan、P. Neta

  DOI：10.1002/kin.550270208

  日期：1995.2

  AbstractLaser flash photolysis (at 248 or 308 nm) or aryl iodides in water or water/methanol solutions produces iodine atoms and phenyl radicals. Iodine atoms react rapidly with added I− to form I2− but do not react rapidly with O2 (k ⩽ 107 L mol−1 s−1). Iodine atoms oxidize phenols to phenoxyl radicals, with rate constants that vary from 1.6 × 107 L mol−1 s−1 for phenol to about 6 × 109 L mol−1 s−1 for 4‐methoxyphenol and hydroquinone. Ascorbate and a Vitamin E analogue are also oxidized very rapidly. N‐Methylindole is oxidized by I atoms to its radical cation with a diffusion‐controlled rate constant, 1.9 × 1010 L mol−1 s−1. Iodine atoms also oxidize sulfite and ferrocyanide ions rapidly but do not add to double bonds. The phenyl radicals, produced along with the I atoms, react with O2 to give phenylperoxyl radicals, which react with phenols much more slowly than I atoms. © 1995 John Wiley & Sons, Inc.