p-chloranil dianion | 55976-90-4

• 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: p-chloranil dianion
• 英文别名: 2,3,5,6-Tetrachlorobenzene-1,4-bis(olate)；2,3,5,6-tetrachlorobenzene-1,4-diolate
• CAS: 55976-90-4
• 化学式: C₆Cl₄O₂
• 分子量: 245.877
• InChiKey: STOSPPMGXZPHKP-UHFFFAOYSA-L

计算性质

• 辛醇/水分配系数(LogP)：
  5
• 重原子数：
  12
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  46.1
• 氢给体数：
  0
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  乙醇 、 p-chloranil dianion 以 乙腈 为溶剂， 生成 2,3,5,6-Tetrachloro-[1,4]benzoquinone; compound with ethanol
  参考文献：
  名称：

  非质子溶剂中醌类电化学中的氢键和质子化效应

  摘要：

  氢键和质子化是控制醌还原电位和机制的基本因素。在苯甲腈、乙腈和二甲亚砜溶液中，在增加氢键能力的羟基添加剂（叔丁醇到六氟 - 2）的存在下，通过一系列碱度增加的醌（氯苯醌到杜罗醌）的循环伏安法系统地研究了这些-丙醇）或酸度（三氟乙酸）。电化学效应在整个相互作用范围内得到证明，从还原二价阴离子的氢键到未还原醌的质子化。随着添加剂浓度的增加，对于弱（I）、中度（II）和强（III）相互作用的醌-添加剂对观察到三种明显不同类型的电化学行为，如下所示：(I) 两个分离良好的还原波，对应于醌单阴离子和二阴离子的形成，正向移动，不损失可逆性。第二波是小...

  DOI：

  10.1021/ja970028j
• 作为产物：
  描述：

  p-chloranilate(1-) 在 1-苯甲基-1,4-二氢烟酰胺 作用下， 以 乙腈 为溶剂， 生成 四氯氰醌 、 p-chloranil dianion
  参考文献：
  名称：

  NADH 类似物对半醌自由基阴离子的 Na+ 催化还原

  摘要：

  NADH 类似物、1-苄基-1,4-二氢烟酰胺 (BNAH) 和 10-甲基-9,10-二氢吖啶 (AcrH2) 可还原对氯苯醌自由基阴离子 (Cl4Q−•) 等稳定的自由基阴离子，从而生成相应的氢醌阴离子。将 NaClO4 添加到 BNAH-Cl4Q-• 系统导致 Cl4Q-• 的单电子还原速率显着增加，而通过添加 Bu4NClO4 没有观察到加速效果。

  DOI：

  10.1246/cl.1992.1497

文献信息

• A Previously Unrecognized Step in Pentachlorophenol Degradation in <i>Sphingobium chlorophenolicum</i> Is Catalyzed by Tetrachlorobenzoquinone Reductase (PcpD)
  作者：MingHua Dai、Julie Bull Rogers、Joseph R. Warner、Shelley D. Copley

  DOI：10.1128/jb.185.1.302-310.2003

  日期：2003.1

  The first step in the pentachlorophenol (PCP) degradation pathway in Sphingobium chlorophenolicum has been believed for more than a decade to be conversion of PCP to tetrachlorohydroquinone. We show here that PCP is actually converted to tetrachlorobenzoquinone, which is subsequently reduced to tetrachlorohydroquinone by PcpD, a protein that had previously been suggested to be a PCP hydroxylase reductase. pcpD is immediately downstream of pcpB , the gene encoding PCP hydroxylase (PCP monooxygenase). Expression of PcpD is induced in the presence of PCP. A mutant strain lacking functional PcpD has an impaired ability to remove PCP from the medium. In contrast, the mutant strain removes tetrachlorophenol from the medium at the same rate as does the wild-type strain. These data suggest that PcpD catalyzes a step necessary for degradation of PCP, but not for degradation of tetrachlorophenol. Based upon the known mechanisms of flavin monooxygenases such as PCP hydroxylase, hydroxylation of PCP should produce tetrachlorobenzoquinone, while hydroxylation of tetrachlorophenol should produce tetrachlorohydroquinone. Thus, we proposed and verified experimentally that PcpD is a tetrachlorobenzoquinone reductase that catalyzes the NADPH-dependent reduction of tetrachlorobenzoquinone to tetrachlorohydroquinone.

  摘要 五氯苯酚（PCP）降解途径中的第一步是 Sphingobium chlorophenolicum 十多年来，人们一直认为五氯苯酚降解途径的第一步是将五氯苯酚转化为四氯对苯二酚。我们在此发现，五氯苯酚实际上转化成了四氯苯醌，随后被 PcpD 还原成四氯氢醌，而 PcpD 蛋白以前曾被认为是五氯苯酚羟化酶还原酶。 pcpD 的下游 pcpB 是编码五氯苯酚羟化酶（五氯苯酚单氧化酶）的基因。PcpD 的表达在五氯苯酚存在时被诱导。缺乏功能性 PcpD 的突变株从培养基中清除五氯苯酚的能力受损。相反，突变株从培养基中清除四氯苯酚的速度与野生型菌株相同。这些数据表明，PcpD 催化了降解五氯苯酚的一个必要步骤，但没有催化降解四氯苯酚的一个必要步骤。根据五氯苯酚羟化酶等黄素单加氧酶的已知机制，五氯苯酚羟化后应产生四氯苯醌，而四氯苯酚羟化后应产生四氯氢醌。因此，我们提出并通过实验验证了 PcpD 是一种四氯对苯醌还原酶，可催化 NADPH 依赖性还原四氯对苯醌为四氯氢醌。
• Verification of the Role of PCP 4-Monooxygenase in Chlorine Elimination from Pentachlorophenol byFlavobacteriumsp. Strain ATCC 39723
  作者：Cleston C. Lange、B.John Schneider、Cindy S. Orser

  DOI：10.1006/bbrc.1996.0196

  日期：1996.2

  bacterial enzyme PCP 4-monooxygenase from Flavobacterium sp. strain ATCC 39723 catalyzes the oxygenolytic removal of the first chlorine from pentachlorophenol. PCP 4-monooxygenase is an FAD binding, NADPH requiring oxygenase, with similar functional domains as other bacterial flavoprotein monooxygenases specific for phenolic substrates. However, the definitive proof for the singular role of an oxygenolytic

  黄杆菌属细菌PCP 4-单加氧酶。菌株ATCC 39723催化从五氯苯酚中氧解除去第一氯。PCP 4-单加氧酶是一种FAD结合，需要加氧酶的NADPH，其功能域与其他对酚类底物特异的细菌黄素蛋白单加氧酶相似。但是，有关黄杆菌属物种从五氯苯酚中氧分解消除伯氯的奇异作用的确凿证据。已经等到了遗传系统的发展，可以通过等位基因交换进行定向诱变，用来自PCP 4-单加氧酶pcpB的相应基因进行诱变。我们报告了黄杆菌属sp的遗传系统的发展。ATCC 39723株
• Confirmation of oxidative dehalogenation of pentachlorophenol by a Flavobacterium pentachlorophenol hydroxylase
  作者：L Xun、E Topp、C S Orser

  DOI：10.1128/jb.174.17.5745-5747.1992

  日期：1992.9

  Pentachlorophenol (PCP) hydroxylase purified from Flavobacterium sp. strain ATCC 39723 converted PCP or 2,3,5,6-tetrachlorophenol to tetrachloro-p-hydroquinone (TeCH) with the co-consumption of O2 and NADPH. The purified enzyme incorporated 18O from 18O2 but not from H218O into the reaction end product TeCH. The results clearly demonstrate that PCP is oxidatively converted to TeCH by a monooxygenase-type

  从Flavobacterium sp。纯化的五氯酚（PCP）羟化酶。菌株ATCC 39723将PCP或2,3,5,6-四氯苯酚转化为四氯对对苯二酚（TeCH），同时消耗O2和NADPH。纯化的酶将18O2中的18O而不是H218O中的18O掺入反应终产物TeCH中。该结果清楚地表明，PCP被黄杆菌属物种的单加氧酶型酶氧化转化为TeCH。株ATCC 39723。
• Diverse substrate range of a Flavobacterium pentachlorophenol hydroxylase and reaction stoichiometries
  作者：L Xun、E Topp、C S Orser

  DOI：10.1128/jb.174.9.2898-2902.1992

  日期：1992.5

  An understanding of the enzymatic reactions catalyzing the degradation of substituted phenols, a major group of environmental pollutants, is required for the development of biological methods for the decontamination of halophenol-polluted sites. We found that a flavomonooxygenase, pentachlorophenol hydroxylase, isolated from a Flavobacterium sp., catalyzed a primary attack on a broad range of substituted phenols, hydroxylating the para position and removing halogen, nitro, amino, and cyano groups to produce halide, nitrite, hydroxylamine, and cyanide, respectively. Elimination of 1 mol of a halogen, nitro, or cyano group required 2 mol of NADPH, while only 1 mol of NADPH was required to remove 1 mol of an amino group or hydrogen.

  了解催化降解取代酚的酶反应是开发生物方法进行卤代酚污染场地净化所必需的。我们发现，从一种黄杆菌中分离出的一种黄酮单加氧酶——五氯酚羟化酶，可对广泛范围的取代酚进行初级攻击，对邻位进行羟基化反应，并去除卤素、硝基、氨基和氰基基团，分别产生卤化物、亚硝酸盐、羟胺和氰化物。消除1摩尔的卤素、硝基或氰基基团需要2摩尔NADPH，而只需要1摩尔NADPH去除1摩尔氨基或氢。
• Biochemical Characterization of the Tetrachlorobenzoquinone Reductase Involved in the Biodegradation of Pentachlorophenol
  作者：Lifeng Chen、Jian Yang

  DOI：10.3390/ijms9030198

  日期：——

  Pentachlorophenol (PCP), a xenobiocide used to preserve lumbers, is a major environmental pollutant in North America. In spite of an expected high resistance to biodegradation, a number of aquatic and soil bacteria can degrade PCP. In this study, we cloned, expressed and purified tetrachlorobenzoquinone reductase (PcpD), the second enzyme in the PCP biodegradation pathway in Sphingobium chlorophenolicum. PcpD, present mainly as a homo-trimer, exhibited low but statistically significant activity in the reduction of tetrachlorobenzoquinone to tetrachlorohydroquinone. The optimal pH for PcpD activity was 7.0. PcpD was stimulated by tetrachlorohydroquinone at low concentrations but inhibited at high concentrations. Because of the constitutive expression and relatively high catalytic efficiency of downstream enzyme tetrachlorohydroquinone reductive dehalogenase, tetrachlorohydroquinone was unlikely to accumulate in high concentrations, suggesting that PcpD would only be stimulated by tetrachlorohydroquinone under in vivo conditions. It was also shown that PcpD was inhibited by PCP in a concentration-dependent manner. Therefore, PcpD was regulated by tetrachlorohydroquinone and PCP using a possible “Yin-Yang” mechanism, which maintained tetrachlorobeanzoquinone at a level that would neither significantly decrease the biodegradation of PCP nor cause cytotoxicity in S. chlorophenolicum cells. Structural model of PcpD showed that the putative tetrachlorobenzoquinone binding site, adjacent to the cofactor flavin mononucleotide and the 2Fe2S cluster, was situated in a deep pit on the surface and slightly positively charged.

  五氯苯酚（PCP）是一种用于木材防腐的异生物杀灭剂，也是北美地区的主要环境污染物。尽管五氯苯酚具有很高的抗生物降解性，但一些水生和土壤细菌可以降解它。在这项研究中，我们克隆、表达并纯化了四氯苯醌还原酶（PcpD），它是氯酚鞘氨醇菌（Sphingobium chlorophenolicum）中五氯苯酚生物降解途径中的第二种酶。PcpD主要以同源三聚体的形式存在，在将四氯苯醌还原为四氯氢醌的过程中表现出低但具有统计学意义的活性。PcpD的最佳pH值为7.0。低浓度四氯氢醌可以刺激PcpD，但高浓度四氯氢醌会抑制它。由于下游酶四氯氢醌还原脱卤酶的恒定表达和相对较高的催化效率，四氯氢醌不太可能以高浓度积累，这表明PcpD只有在体内条件下才会被四氯氢醌刺激。研究还表明，PcpD受五氯苯酚的浓度依赖性抑制。因此，PcpD受四氯氢醌和五氯苯酚的调节，可能采用“阴阳”机制，将四氯苯醌维持在既不会显著降低五氯苯酚生物降解性，也不会导致氯