4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidin-1-oxyl radical

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 喹啉及其衍生物
• 英文名称: 4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidin-1-oxyl radical
• 英文别名: 4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidine-1-oxyl；4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidine-1-oxyl free radical；4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidin-1-oxyl
• 化学式: C₂₀H₂₅N₂O₄
• 分子量: 357.429
• InChiKey: MZOSCDGBLCHWLL-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  4
• 重原子数：
  26
• 可旋转键数：
  3
• 环数：
  3.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  63.7
• 氢给体数：
  1
• 氢受体数：
  5

反应信息

• 作为反应物：
  描述：

  4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidin-1-oxyl radical 在 维生素 C 作用下， 生成 (1-Hydroxy-2,2,6,6-tetramethylpiperidin-4-yl) 3-hydroxy-2-methylquinoline-4-carboxylate
  参考文献：
  名称：

  预荧光氮氧化物探针 QT 和 C343T 的光物理特性

  摘要：

  氮氧化物预荧光探针4-(3-羟基-2-甲基-4-喹啉氧基)-2,2,6,6-四甲基-哌啶-4-基)酯自由基(QT)和2,3的光物理性质,4,6,7,8-六氢-喹啉基 [1,10,9-gh] 香豆素-3-羧酸（1-氧基-2,2,6,6-四甲基-哌啶-4-基）酯自由基 (C343T) 作为 pH 值和溶剂性质的函数进行评估。QT 的吸光度显示出高 pH 敏感性。涉及喹啉发色团酸碱平衡的不同电离形式的 pKa 值是在基态和激发态下确定的。QT、N-羟胺（QTH）和喹啉甲酯（QMe）衍生物的荧光寿命表明，硝基氧部分的分子内猝灭效率与喹啉电离形式无关。C343T 的荧光和吸光度对溶剂极性高度敏感，与生色团的带电转移激发态一致。然而，我们注意到当将溶剂的极性从己烷变为水时，硝基氧部分会降低分子内荧光猝灭效率。这种行为归因于在极极性溶剂中氮氧化合物淬灭过程中能量转移机制的抑制。在胶束中获得的结果使我们能够建议

  DOI：

  10.1111/j.1751-1097.2008.00381.x
• 作为产物：
  描述：

  2-甲基-3-羟基喹啉-4-羧酸 、 阻聚剂701 在 4-二甲氨基吡啶 、 盐酸-N-乙基-Nˊ-(3-二甲氨基丙基)碳二亚胺 作用下， 以 二氯甲烷 为溶剂， 反应 6.0h， 生成 4-(3-hydroxy-2-methyl-4-quinolinoyloxy)-2,2,6,6-tetramethylpiperidin-1-oxyl radical
  参考文献：
  名称：

  使用荧光前喹啉-TEMPO传感器监测的聚甲基丙烯酸甲酯薄膜中的自由基反应

  摘要：

  研究了4-（3-羟基-2-甲基-4-喹啉基氧基）-2,2,6,6-四甲基哌啶-1-氧基自由基（QT）的光化学和光物理性质，以监测游离聚合物膜中的自由基过程。该方法利用顺磁性氮氧化物对喹啉荧光进行有效的分子内淬灭，当TEMPO与以碳为中心的自由基反应时，该方法将被禁用。在聚甲基丙烯酸甲酯（PMMA）薄膜中2,2'-偶氮二异丁腈（AIBN）的热分解中观察到的荧光强度-时间曲线表明，随着时间的推移，荧光随时间的变化出现了初始增加。通过QT使自由基在聚合物膜中居中。在氮和氧饱和条件下的数据比较表明，在90°C时，以碳为中心的自由基的氧捕获比与氮氧化物的反应快约20倍。在PMMA中用于AIBN分解的活化能被测量为34.1kcal / mol。荧光寿命分布的分析确定了AIBN对反磁性反应产物的静态和动态荧光猝灭的参与。

  DOI：

  10.1021/ma0212994

文献信息

• Novel Excited Quintet State in Porphyrin:  Bis(quinoline−TEMPO)−yttrium−tetraphenylporphine Complex
  作者：Luca Maretti、Saiful S. M. Islam、Yasunori Ohba、Takashi Kajiwara、Seigo Yamauchi

  DOI：10.1021/ic0511827

  日期：2005.12.1

  synthesized, and the properties of the excited states generated by photoexcitation of porphyrin were studied by time-resolved (TR) and pulsed two-dimensional electron paramagnetic resonance (EPR) spectroscopy. A TR-EPR spectrum was observed in the quartet (S=3/2) or quintet (S=2) states generated from interactions of one or two radicals with the photoexcited triplet state of the porphyrin. The zero-field

  合成了新的单和双[4-（3-羟基-2-甲基-4-喹啉基酰氧基）-2,2,6,6-四甲基哌啶-1-氧基]（内消旋四苯基卟啉酮）钇（III）配合物，通过时间分辨（TR）和脉冲二维电子顺磁共振（EPR）光谱研究了卟啉的光激发产生的激发态的性质。在一个或两个自由基与卟啉的光激发三重态相互作用产生的四重态（S = 3/2）或五重态（S = 2）中观察到TR-EPR光谱。根据三重态和自由基-三重态对分析了这些状态的零场分裂D值。通过测量脉冲EPR的突变频率，可以明确分配激发态的自旋态。
• Photophysical Properties of the Prefluorescent Nitroxide Probes QT and C₃₄₃T
  作者：Claudia Bueno、Larisa Mikelsons、Luca Maretti、J. C. Scaiano、Alexis Aspée

  DOI：10.1111/j.1751-1097.2008.00381.x

  日期：2008.11

  properties of the nitroxide prefluorescent probes 4‐(3‐hydroxy‐2‐methyl‐4‐quinolinoyloxy)‐2,2,6,6‐tetramethyl‐piperidin‐4‐yl) ester free radical (QT) and 2,3,4,6,7,8‐hexahydro‐quinolizino [1,10,9‐gh] coumarin‐3‐carboxylic acid (1‐oxyl‐2,2,6,6‐tetramethyl‐piperidin‐4‐yl) ester free radical (C343T) were evaluated as a function of pH and solvent properties. The absorbance of QT showed high pH sensitivity. The

  氮氧化物预荧光探针4-(3-羟基-2-甲基-4-喹啉氧基)-2,2,6,6-四甲基-哌啶-4-基)酯自由基(QT)和2,3的光物理性质,4,6,7,8-六氢-喹啉基 [1,10,9-gh] 香豆素-3-羧酸（1-氧基-2,2,6,6-四甲基-哌啶-4-基）酯自由基 (C343T) 作为 pH 值和溶剂性质的函数进行评估。QT 的吸光度显示出高 pH 敏感性。涉及喹啉发色团酸碱平衡的不同电离形式的 pKa 值是在基态和激发态下确定的。QT、N-羟胺（QTH）和喹啉甲酯（QMe）衍生物的荧光寿命表明，硝基氧部分的分子内猝灭效率与喹啉电离形式无关。C343T 的荧光和吸光度对溶剂极性高度敏感，与生色团的带电转移激发态一致。然而，我们注意到当将溶剂的极性从己烷变为水时，硝基氧部分会降低分子内荧光猝灭效率。这种行为归因于在极极性溶剂中氮氧化合物淬灭过程中能量转移机制的抑制。在胶束中获得的结果使我们能够建议
• Spin Coupling in the Supramolecular Structure of a New Tetra(Quinoline−TEMPO)Yttrium(III) Complex
  作者：Luca Maretti、Marilena Ferbinteanu、Fanica Cimpoesu、Saiful S. M. Islam、Yasunori Ohba、Takashi Kajiwara、Masahiro Yamashita、Seigo Yamauchi

  DOI：10.1021/ic0610841

  日期：2007.2.1

  The newly synthesized tetra(quinoline-TEMPO)yttrium(III) potassium salt shows interesting structural features at the molecular and supramolecular levels, revealed by the analysis of the X-ray diffraction data. The magnetic susceptibility and EPR data corroborated with structural considerations showed that the exchange and dipolar spin coupling interactions are taking place at the nodes assembling the supramolecular 2D structure. The Y(III) center shows antiprismatic octacoordination, close to the idealized D-2 symmetry. The diamagnetic transition metal plays no role in mediating the radical interactions since the TEMPO-type fragments are remote from the chelating moieties of the ligand. In turn, significant interaction occurs on the nodes consisting in the quasi-rectangular coordination of potassium counterions by the spin-bearing TEMPO groups coming from four distinct complex units. The antiferromagnetic susceptibility was consistently modeled by a spin Hamiltonian based on the rectangle topology of four spins S = (1)/(2). The fitted exchange parameters are J(a) = -5.1 cm(-1) and J(b) = -3.4 cm(-1) for the edges, imposing J(d) = 0 for the diagonal. These values are in excellent agreement with the ab initio results J(a) = -4.83 cm(-1), J(b) = -3.44 cm(-1), J(d) = -0.07 cm(-1) obtained in a CASSCF(12,8) calculation. Based on the reliability of the ab initio results we were able to select the presented J parameters among several versions of multiple solutions with acceptable goodness of the fit. A methodological caveat about the artifacts of the automatic use of best fit parameters, in the absence of supplementary criteria, in the context of relative blindness of magnetic susceptibility modeling, is raised. The details of the EPR spectrum at 10 K are also consistent, in the frame of dipolar approximation, with the model of four interacting spins at the nodes of the supramolecular assembling.
• Free Radical Reactions in Poly(methyl methacrylate) Films Monitored Using a Prefluorescent Quinoline−TEMPO Sensor
  作者：Alexis Aspée、Olga García、Luca Maretti、Roberto Sastre、J. C. Scaiano

  DOI：10.1021/ma0212994

  日期：2003.5.1

  xy)-2,2,6,6-tetramethylpiperidine-1-oxyl free radical (QT) have been studied as a prefluorescent probe to monitor free radical processes in polymer films. This methodology takes advantage of the efficient intramolecular quenching of the fluorescence of quinoline by the paramagnetic nitroxide, which is disabled when TEMPO reacts with carbon-centered radicals. The fluorescence intensity−time profile

  研究了4-（3-羟基-2-甲基-4-喹啉基氧基）-2,2,6,6-四甲基哌啶-1-氧基自由基（QT）的光化学和光物理性质，以监测游离聚合物膜中的自由基过程。该方法利用顺磁性氮氧化物对喹啉荧光进行有效的分子内淬灭，当TEMPO与以碳为中心的自由基反应时，该方法将被禁用。在聚甲基丙烯酸甲酯（PMMA）薄膜中2,2'-偶氮二异丁腈（AIBN）的热分解中观察到的荧光强度-时间曲线表明，随着时间的推移，荧光随时间的变化出现了初始增加。通过QT使自由基在聚合物膜中居中。在氮和氧饱和条件下的数据比较表明，在90°C时，以碳为中心的自由基的氧捕获比与氮氧化物的反应快约20倍。在PMMA中用于AIBN分解的活化能被测量为34.1kcal / mol。荧光寿命分布的分析确定了AIBN对反磁性反应产物的静态和动态荧光猝灭的参与。
• Antioxidant reactivity toward nitroxide probes anchored into human serum albumin. A new model for studying antioxidant repairing capacity of protein radicals
  作者：Alexis Aspée、Alejandra Orrego、Emilio Alarcón、Camilo López-Alarcón、Horacio Poblete、Danilo González-Nilo

  DOI：10.1016/j.bmcl.2009.09.070

  日期：2009.11

  A new strategy to evaluate accessibility of antioxidants to radical proteins has been developed using nitroxide prefluorescent probes anchored into human serum albumin (HSA). Binding association constants for the nitroxide probes C343T and QT with HSA were 5 x 10(4) and 9 x 10(4) M-1, respectively. Rate constants for the nitroxide reduction by antioxidants in HSA were determined finding k(HSA)/k(buffer) ratio of 0.8, 1.9, and 0.075 for ascorbic acid, Trolox, and caffeic acid, respectively, for the nitroxide C343T reduction. (C) 2009 Elsevier Ltd. All rights reserved.