5,5',6,6'-tetrahydroxy-2,4'-biindolyl | 133991-50-1

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吲哚及其衍生物
• 英文名称: 5,5',6,6'-tetrahydroxy-2,4'-biindolyl
• 英文别名: 5,5',6,6'-tetrahydoxy-2,4'-biindolyl；5,5',6,6'-tetrahydroxy-2,4'biindolyl；2-(5,6-dihydroxy-1H-indol-4-yl)-1H-indole-5,6-diol；4-(5,6-dihydroxy-1H-indol-2-yl)-1H-indole-5,6-diol
• CAS: 133991-50-1
• 化学式: C₁₆H₁₂N₂O₄
• 分子量: 296.282
• InChiKey: KXVRIZRVTJPCMG-UHFFFAOYSA-N

物化性质

• 沸点：
  741.1±60.0 °C(Predicted)
• 密度：
  1.709±0.06 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.4
• 重原子数：
  22
• 可旋转键数：
  1
• 环数：
  4.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  113
• 氢给体数：
  6
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  5,5',6,6'-tetrahydroxy-2,4'-biindolyl 在 potassium dihydrogenphosphate 、 双氧水 、 horseradish peroxidase 作用下， 以 甲醇 、 phosphate buffer 为溶剂， 反应 0.01h， 生成 3,5,5',6,6'-tetrahydroxy-2,4'biindolyl
  参考文献：
  名称：

  从 5,6-二羟基吲哚二聚体到真黑素聚合物的短寿命醌类物质：综合化学、脉冲辐射分解和量子力学研究

  摘要：

  已经研究了由 5,6-二羟基吲哚 (1) 的三个二聚体氧化形成的瞬态物种，这是天然生物聚合物真黑色素的主要组成部分。5,5',6,6'-四羟基-2,4'-二吲哚基 (3) 和 5,5',6,6'-四羟基-2,7'-二吲哚基 (4) 的脉冲辐解氧化导致半醌吸收大约 450 nm，它以二级动力学（分别为 2k=2.8x10(9) 和 1.4x10(9) M-1 s-1）衰减，得到相应的醌（500-550 nm）。另一方面，5,5',6, 6'-四羟基-2,2'-二吲哚基 (2) 提供了一种半醌 (lamdamax=480 nm)，其歧化速率相当 (2k=3x10(9) M -1 s-1) 得到相对稳定的醌 (lamdamax=570 nm)。邻醌、醌亚胺的量子力学研究 2-4 的醌甲基化物结构表明氧化的 2-4 主要以 2-取代的扩展醌甲基化物互变异构体形式存在。最后，首次分离出 3 的氧化产物，并将其配制成羟基化衍生物

  DOI：

  10.1021/ja0650246
• 作为产物：
  描述：

  5,5',6,6'-tetraacetoxy-2,4'-biindolyl 在 sodium phosphate 、 potassium bromide 作用下， 以 甲醇 为溶剂， 反应 0.02h， 生成 5,5',6,6'-tetrahydroxy-2,4'-biindolyl
  参考文献：
  名称：

  从 5,6-二羟基吲哚二聚体到真黑素聚合物的短寿命醌类物质：综合化学、脉冲辐射分解和量子力学研究

  摘要：

  已经研究了由 5,6-二羟基吲哚 (1) 的三个二聚体氧化形成的瞬态物种，这是天然生物聚合物真黑色素的主要组成部分。5,5',6,6'-四羟基-2,4'-二吲哚基 (3) 和 5,5',6,6'-四羟基-2,7'-二吲哚基 (4) 的脉冲辐解氧化导致半醌吸收大约 450 nm，它以二级动力学（分别为 2k=2.8x10(9) 和 1.4x10(9) M-1 s-1）衰减，得到相应的醌（500-550 nm）。另一方面，5,5',6, 6'-四羟基-2,2'-二吲哚基 (2) 提供了一种半醌 (lamdamax=480 nm)，其歧化速率相当 (2k=3x10(9) M -1 s-1) 得到相对稳定的醌 (lamdamax=570 nm)。邻醌、醌亚胺的量子力学研究 2-4 的醌甲基化物结构表明氧化的 2-4 主要以 2-取代的扩展醌甲基化物互变异构体形式存在。最后，首次分离出 3 的氧化产物，并将其配制成羟基化衍生物

  DOI：

  10.1021/ja0650246

文献信息

• 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.
• 5,6-Dihydroxyindole Oxidation in Phosphate Buffer/Polyvinyl Alcohol: A New Model System for Studies of Visible Chromophore Development in Synthetic Eumelanin Polymers
  作者：Alessandro Pezzella、Veronica Ambrogi、Marianna Arzillo、Alessandra Napolitano、Cosimo Carfagna、Marco D’Ischia

  DOI：10.1111/j.1751-1097.2010.00730.x

  日期：——

  AbstractThe determinants of the broadband absorption spectrum of eumelanins are still largely unknown. Herein we report a novel approach to investigate eumelanin chromophore which is based on the biomimetic oxidation of the key monomer precursor, 5,6‐dihydroxyindole (DHI, 1), with peroxidase/hydrogen peroxide in phosphate buffer, pH 7, containing 1–5% polyvinylalcohol (PVA, 27 000 Da). This approach relies on the discovery that as low as 1% PVA can prevent precipitation of the growing melanin polymer thus allowing investigation of the chromophoric phases accompanying oxidation of DHI without confounding scattering effects. Spectrophotometric monitoring showed the initial development of a band around 530 nm persisting for about 1 h before gradually changing into the typical broadband spectrum of eumelanin. Reductive treatment caused a significant absorbance decrease in the visible region without affecting an absorption band around 320 nm. Initial product analysis indicated an altered formation ratio of 2,4′‐biindolyl (2) and 2,7′‐biindolyl (3) relative to control experiments. Overall, these results demonstrate for the first time that the development in solution of visible chromophores since the early oligomer stages is independent of strong aggregation/precipitation phenomena.
• Short-Lived Quinonoid Species from 5,6-Dihydroxyindole Dimers en Route to Eumelanin Polymers:  Integrated Chemical, Pulse Radiolytic, and Quantum Mechanical Investigation
  作者：Alessandro Pezzella、Lucia Panzella、Orlando Crescenzi、Alessandra Napolitano、Suppiah Navaratman、Ruth Edge、Edward J. Land、Vincenzo Barone、Marco d'Ischia

  DOI：10.1021/ja0650246

  日期：2006.12.1

  The transient species formed by oxidation of three dimers of 5,6-dihydroxyindole (1), a major building block of the natural biopolymer eumelanin, have been investigated. Pulse radiolytic oxidation of 5,5',6,6'-tetrahydroxy-2,4'-biindolyl (3) and 5,5',6,6'-tetrahydroxy-2,7'-biindolyl (4) led to semiquinones absorbing around 450 nm, which decayed with second-order kinetics (2k=2.8x10(9) and 1.4x10(9)

  已经研究了由 5,6-二羟基吲哚 (1) 的三个二聚体氧化形成的瞬态物种，这是天然生物聚合物真黑色素的主要组成部分。5,5',6,6'-四羟基-2,4'-二吲哚基 (3) 和 5,5',6,6'-四羟基-2,7'-二吲哚基 (4) 的脉冲辐解氧化导致半醌吸收大约 450 nm，它以二级动力学（分别为 2k=2.8x10(9) 和 1.4x10(9) M-1 s-1）衰减，得到相应的醌（500-550 nm）。另一方面，5,5',6, 6'-四羟基-2,2'-二吲哚基 (2) 提供了一种半醌 (lamdamax=480 nm)，其歧化速率相当 (2k=3x10(9) M -1 s-1) 得到相对稳定的醌 (lamdamax=570 nm)。邻醌、醌亚胺的量子力学研究 2-4 的醌甲基化物结构表明氧化的 2-4 主要以 2-取代的扩展醌甲基化物互变异构体形式存在。最后，首次分离出 3 的氧化产物，并将其配制成羟基化衍生物
• The First 5,6-Dihydroxyindole Tetramer by Oxidation of 5,5‘,6,6‘-Tetrahydroxy- 2,4‘-biindolyl and an Unexpected Issue of Positional Reactivity en Route to Eumelanin-Related Polymers
  作者：Lucia Panzella、Alessandro Pezzella、Alessandra Napolitano、Marco d'Ischia

  DOI：10.1021/ol070268w

  日期：2007.3.1

  The first tetramer of the eumelanin precursor 5,6-dihydroxyindole has been obtained, as the acetyl derivative, by peroxidase/H2O2-induced oxidative coupling of 5,5',6,6'-tetrahydroxy-2,4'-biindolyl (2) in the presence of Zn2+ ions. The tetramer, 5,5',5' ',5' '',6,6',6' ',6' ''-octaacetoxy-2,4':2',3' ':2' ',4' ''-tetraindolyl (acetylated 7), incorporates an unprecedented 2,3'-biindolyl substructure suggestive of a different positional reactivity of the 5,6-dihydroxyindole system when framed into a dimeric scaffold.