2,2'-dicarboxy-5,5',6,6'-tetrahydroxy-4,4'-biindolyl | 133991-54-5

• 分子结构分类: 有机化合物 - 苯类化合物 - 苯和取代衍生物
• 英文名称: 2,2'-dicarboxy-5,5',6,6'-tetrahydroxy-4,4'-biindolyl
• 英文别名: 5,5',6,6'-tetrahydroxy-2,2'-carboxy-4,4'-biindolyl；4-(2-carboxy-5,6-dihydroxy-1H-indol-4-yl)-5,6-dihydroxy-1H-indole-2-carboxylic acid
• CAS: 133991-54-5
• 化学式: C₁₈H₁₂N₂O₈
• 分子量: 384.302
• InChiKey: FXOYAOLSFLTAPO-UHFFFAOYSA-N

物化性质

• 沸点：
  957.8±65.0 °C(Predicted)
• 密度：
  1.937±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.1
• 重原子数：
  28
• 可旋转键数：
  3
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  187
• 氢给体数：
  8
• 氢受体数：
  8

反应信息

• 作为反应物：
  描述：

  2,2'-dicarboxy-5,5',6,6'-tetrahydroxy-4,4'-biindolyl 在 双氧水 、 potassium carbonate 作用下， 生成 2,3,5-三羧酸吡咯
  参考文献：
  名称：

  Oxidative degradation of melanins to pyrrole acids: A model study

  摘要：

  The origin of pyrrole-2,3,5-tricarboxylic acid (PTCA), the most characteristic degradation product of melanins, was investigated by use of synthetic pigments prepared from the major biosynthetic precursors, 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA). Under the reported conditions, i.e. acidic permanganate, oxidative degradation of DHI- and DHICA-melanins afforded PTCA in 0.15 and 3.0% w/w yield, respectively. A significant improvement of PTCA yields up to 7% was obtained using alkaline hydrogen peroxide as the oxidising agent. Under these conditions pyrrole-2,3-dicarboxylic acid (PDCA) was also obtained in significant yields. Investigation of the oxidative degradation of some model indole oligomers (1-4) provided unambiguous evidence that PTCA may originate from 2-linked DHI-units in the pigment polymer as well as from DHICA-derived units, whereas PDCA arises from DHI-units not substituted at 2-position. Monitoring of the oxidation of dimer 1 to PTCA showed the intermediate formation of DHICA. Accordingly, a mechanistic route is proposed for the degradation of 2-substituted DHI-units in melanin polymer to PTCA which also accounts for the observed yields of formation of the pyrrole acid from the model oligomers.

  DOI：

  10.1016/0040-4020(95)00259-b
• 作为产物：
  描述：

  5,6-二羟基-2-吲哚甲酸 在 Tris buffer 、 氧气 、 copper(II) sulfate 作用下， 反应 0.17h， 以95%的产率得到2,2'-dicarboxy-5,5',6,6'-tetrahydroxy-4,4'-biindolyl
  参考文献：
  名称：

  Synthesis of optically active tetrameric melanin intermediates by oxidation of the melanogenic precursor 5,6-dihydroxyindole-2-carboxylic acid under biomimetic conditions

  摘要：

  In a recent work addressing the structural characterization of melanin pigments, we reported the isolation and characterization of trimeric oligomers of 5,6-dihydroxyindole-2-carboxylic acid (DHICA), a key intermediate in the biosynthesis of the dark brown eumelanins, by tyrosine catalyzed oxidation of the indole under biomimetic conditions. These oligomers feature atropisomerism and consequently, we wished to investigate chirality in such systems. Herein, we report two significant steps forward in this study: The isolation of a regiosymmetric DHICA tetramer by means of a model approach involving oxidation of the main DHICA dimer, namely 4,4'-biindolyl and the first resolution of eumelanin intermediates. This also allowed the absolute stereochemistry of the newly isolated tetramer to be defined by applying the exiton chirality method. (C) 2003 Elsevier Science Ltd. All rights reserved.

  DOI：

  10.1016/s0957-4166(03)00156-3

文献信息

• 5,6-Dihydroxyindoles in the Fenton Reaction:  A Model Study of the Role of Melanin Precursors in Oxidative Stress and Hyperpigmentary Processes
  作者：Luisa Novellino、Alessandra Napolitano、Giuseppe Prota

  DOI：10.1021/tx990020i

  日期：1999.10.1

  merely as pigment precursors, but may also act as modulators of the responses of the pigmentary cell melanocyte to external stimuli, especially to inflammation. In this study, the effect of melanin precursors 5, 6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) on the Fenton-induced oxidation of deoxyribose was investigated as a model of the oxidative stress processes triggered

  越来越多的证据支持以下观点：可扩散的黑色素相关代谢物不仅充当色素前体，而且还可能充当色素细胞黑素细胞对外部刺激（尤其是对炎症）的反应的调节剂。在这项研究中，作为触发氧化应激过程的模型，研究了黑色素前体5、6-二羟基吲哚（DHI）和5,6-二羟基吲哚-2-羧酸（DHICA）对Fenton诱导的脱氧核糖氧化的影响。通过发炎期间铁的释放。DHICA在有氧和厌氧条件下均对H（2）O（2）-Fe（II）/ EDTA氧化产生了强大的抑制作用，即使在低浓度下也被证明比典型的羟基自由基（HO（*））清除剂更有效关于脱氧核糖。相反，空气中的DHI是低吲哚的促氧化剂：Fe（II）比率，但以较高比率（> 6）转变为抗氧化剂。通过降低培养基的pH值或通过用Fe（III）代替Fe（II），可以增加前氧化作用的强度，但通过排除氧气可以抑制这种作用。分光光度法实验证明，两种吲哚在没有EDTA的情况下都保留了对Fento
• Oxidative polymerisation of 5,6-dihydroxyindole-2-carboxylic acid to melanin: A new insight
  作者：Alessandro Pezzella、Alessandra Napolitano、Marco d'Ischia、Giuseppe Prota

  DOI：10.1016/0040-4020(96)00362-6

  日期：1996.6

  oxidative polymerisation of 5,6-dihydroxyindole-2-carboxylic acid, a key intermediate in the biosynthesis of eumelanins, had delineated a reaction pathway involving mainly repeated coupling of the indole units through the 4- and 7- positions. Using an improved HPLC methodology for the direct analysis of oligomer intermediates, we have now obtained evidence for a more complex mode of polymerisation, involving

  先前关于5，6-二羟基吲哚-2-羧酸（真木兰生物合成中的关键中间体）的氧化聚合的研究已经勾勒出一条反应途径，该途径主要涉及吲哚单元通过4-和7-位的重复偶联。使用改进的HPLC方法直接分析低聚物中间体，我们现已获得证明，除了4,4'和4,7'偶联的二聚体5和6外，还有更复杂的聚合反应模式，包括形成反应。，是三个新的二聚体中的一个，它们已经被分离并鉴定为3,4'-，3,7'-和7,7'-二吲哚7-9。在5,6-二羟基吲哚的氧化聚合反应中，观察到的3-位的含义是空前的，并为今后的研究提供了重要的线索，旨在阐明天然和合成双聚木聚糖的化学组成。
• Lack of Visible Chromophore Development in the Pulse Radiolysis Oxidation of 5,6-Dihydroxyindole-2-carboxylic Acid Oligomers: DFT Investigation and Implications for Eumelanin Absorption Properties
  作者：Alessandro Pezzella、Lucia Panzella、Orlando Crescenzi、Alessandra Napolitano、Suppiah Navaratnam、Ruth Edge、Edward J. Land、Vincenzo Barone、Marco d’Ischia

  DOI：10.1021/jo900250v

  日期：2009.5.15

  The structural factors underlying the peculiar optical properties and visible chromophore of eumelanin biopolymers are largely uncharted. It is known that synthetic eumelanins from 5,6-dihydroxyindole are black and display a featureless UV−visible absorption spectrum, whereas those from 5,6-dihydroxyindole-2-carboxylic acid (1) are lighter in color and exhibit a distinct band around 310 nm, but the origin

  Eumelanin生物聚合物特有的光学特性和可见生色团的潜在结构因素在很大程度上尚未阐明。已知的是，从5,6-二羟基吲哚的合成真黑素是黑和显示特征的紫外-可见吸收光谱，而那些从5,6-二羟基吲哚-2-羧酸（1）颜色较浅和周围表现出明显的带310 nm，但这种差异的根源尚未得到详细解决。最近，我们发现5,6-二羟基吲哚二聚体在脉冲辐射分解氧化作用下产生，可强烈吸收在500-600 nm区域具有强烈最大值的瞬态，这被归因于平面扩展的醌甲基化物。现在我们报告3个低聚物与1个的出乎意料的不同行为，即4,4'-联吲哚2，所述-4,7'-联吲哚3和4,7'：4'，7'' - terindolyl 4。的脉冲辐解氧化2 - 4最初导致在360-380纳米具有类似的吸收最大值半醌中间体。半醌吸收衰减后跟第二级动力学（2 ķ = 1.4×10 8 3.2×10 8和1.4×10 8中号-1小号-1为2，3，
• Oxidative degradation of melanins to pyrrole acids: A model study
  作者：Alessandra Napolitano、Alessandro Pezzella、M.Rosaria Vincensi、Giuseppe Prota

  DOI：10.1016/0040-4020(95)00259-b

  日期：1995.5

  The origin of pyrrole-2,3,5-tricarboxylic acid (PTCA), the most characteristic degradation product of melanins, was investigated by use of synthetic pigments prepared from the major biosynthetic precursors, 5,6-dihydroxyindole (DHI) and 5,6-dihydroxyindole-2-carboxylic acid (DHICA). Under the reported conditions, i.e. acidic permanganate, oxidative degradation of DHI- and DHICA-melanins afforded PTCA in 0.15 and 3.0% w/w yield, respectively. A significant improvement of PTCA yields up to 7% was obtained using alkaline hydrogen peroxide as the oxidising agent. Under these conditions pyrrole-2,3-dicarboxylic acid (PDCA) was also obtained in significant yields. Investigation of the oxidative degradation of some model indole oligomers (1-4) provided unambiguous evidence that PTCA may originate from 2-linked DHI-units in the pigment polymer as well as from DHICA-derived units, whereas PDCA arises from DHI-units not substituted at 2-position. Monitoring of the oxidation of dimer 1 to PTCA showed the intermediate formation of DHICA. Accordingly, a mechanistic route is proposed for the degradation of 2-substituted DHI-units in melanin polymer to PTCA which also accounts for the observed yields of formation of the pyrrole acid from the model oligomers.
• Synthesis of optically active tetrameric melanin intermediates by oxidation of the melanogenic precursor 5,6-dihydroxyindole-2-carboxylic acid under biomimetic conditions
  作者：Alessandro Pezzella、Davide Vogna、Giuseppe Prota

  DOI：10.1016/s0957-4166(03)00156-3

  日期：2003.5

  In a recent work addressing the structural characterization of melanin pigments, we reported the isolation and characterization of trimeric oligomers of 5,6-dihydroxyindole-2-carboxylic acid (DHICA), a key intermediate in the biosynthesis of the dark brown eumelanins, by tyrosine catalyzed oxidation of the indole under biomimetic conditions. These oligomers feature atropisomerism and consequently, we wished to investigate chirality in such systems. Herein, we report two significant steps forward in this study: The isolation of a regiosymmetric DHICA tetramer by means of a model approach involving oxidation of the main DHICA dimer, namely 4,4'-biindolyl and the first resolution of eumelanin intermediates. This also allowed the absolute stereochemistry of the newly isolated tetramer to be defined by applying the exiton chirality method. (C) 2003 Elsevier Science Ltd. All rights reserved.