glycine anhydride α-centred radical | 7256-30-6

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: glycine anhydride α-centred radical
• CAS: 7256-30-6
• 化学式: C₄H₅N₂O₂
• 分子量: 113.096
• InChiKey: GOOFZIZXFYXAIL-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  -1.3
• 重原子数：
  8
• 可旋转键数：
  0
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.25
• 拓扑面积：
  58.2
• 氢给体数：
  2
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  glycine anhydride α-centred radical 在 水 、 hexacyanoferrate(III) 作用下， 生成 3-羟基-2,5-哌嗪二酮
  参考文献：
  名称：

  Mieden, Oliver J.; Sonntag, Clemens von, Zeitschrift fur Naturforschung, B: Chemical Sciences, 1989, vol. 44, # 8, p. 959 - 974

  摘要：

  DOI：
• 作为产物：
  描述：

  甘氨酸酐 在 半胱胺自由基 、 异丙醇 作用下， 以 重水 为溶剂， 生成 glycine anhydride α-centred radical
  参考文献：
  名称：

  硫基自由基从模型肽中的 αC-H 键中提取氢原子：绝对速率常数和氨基酸结构的影响

  摘要：

  硫基自由基是生物氧化应激和酶促反应中的重要中间体，例如核糖核苷酸还原酶。仅基于均裂键解离能 (BDE)，肽和蛋白质的 (α)CH 键将成为硫自由基夺氢的合适目标。然而，极性和构象效应等附加参数可能会控制这种氢转移过程。为了评估硫基自由基从 (alpha)CH 键中提取氢的潜力，我们提供了这些与模型肽反应的第一个绝对速率常数。硫基自由基与 (alpha)CH 键反应，速率常数介于 1.7 x 10(3) M(-1) s(-1)（N-乙酰脯氨酸酰胺）和 4 x 10(5) M(-1) s(- 1) (肌氨酸酐)。然而，速率常数与 BDE 的相关性很差。

  DOI：

  10.1021/ja0293599

文献信息

• H-Atom abstraction by C-centered radicals from cyclic and acyclic dipeptides. A theoretical and experimental study of reaction rates
  作者：Darren L. Reid、David A. Armstrong、Arvi Rauk、Chandrasekhar Nese、Man Nien Schuchmann、Ursula Westhoff、Clemens von Sonntag

  DOI：10.1039/b303223j

  日期：——

  Using the pulse radiolysis and other radiation chemical techniques, the reaction kinetics of ˙CH3 and ˙CH2OH radicals with alanine anhydride, glycine anhydride and sarcosine anhydride were examined in aqueous solution. The second order rate constant of reaction of ˙CH3 with alanine anhydride has been determined at 2 × 105 dm3 mol−1 s−1. A very similar value (8 × 104 dm3 mol−1 s−1) has been obtained

  利用脉冲辐解和其他辐射化学技术，研究了˙CH3和˙CH2OH自由基与丙氨酸酐、甘氨酸酐和肌氨酸酐在水溶液中的反应动力学。˙CH3 与丙氨酸酐反应的二级速率常数已确定为 2 × 105 dm3 mol-1 s-1。通过测量甲烷和乙烷产率作为不同剂量率下丙氨酸酐浓度的函数并通过计算机分析评估这些数据，获得了非常相似的值 (8 × 104 dm3 mol-1 s-1)。用甘氨酸酐和肌氨酸酐进行的类似实验对这些化合物产生了相同的速率常数，均为 4 × 104 dm3 mol-1 s-1。发现˙CH2OH自由基不与丙氨酸酐以可观的速率反应（k < 2 × 102 dm3 mol-1 s-1）。通过B3LYP/6-311+G(d,p)理论水平的理论计算研究了˙CH3、˙CH2OH和˙C(CH3)2OH与环状酸酐和无环甘氨酸和丙氨酸肽的反应. 气相中的自由能在经典的谐振子-刚性转子模型中确定，并用于估计肽的αC位点的氢转移反应速率。通过
• Peptide peroxyl radicals: base-induced superoxide radical ion elimination versus bimolecular decay. A pulse radiolysis and product study
  作者：Oliver J. Mieden、Man Nien Schuchmann、Clemens von Sonntag

  DOI：10.1021/j100117a026

  日期：1993.4

  Radiolytically generated OH radicals react with the cyclic dipeptides glycine anhydride (1) and alanine anhydride (2), forming a single type of peptide radical in each case by abstracting a carbon-bound H atom at the ring. In the case of sarcosine anhydride (3), besides the C(3) or C(6) H atoms (78%), the H atoms at the N-methyl groups are also targets of the OH radical attack (22%). In N2O/O2 (4:1 v/v) saturated solutions these peptide radicals add oxygen (k almost-equal-to 2 x 10(9) dm3 mol-1 s-1) to form the corresponding peroxyl radicals 6 (from 1), 7 (from 2), and 12 and 13 (from 3). The kinetics of O2.- elimination from the radicals 6 and 7 has been monitored by pulse radiolysis techniques. The pK(a) values of the peroxyl radicals 6 and 7 have been determined to be 10.8 and 11.2, respectively. The anions of these peroxyl radicals (6a and 7a) rapidly eliminate O2.- with the rate constants 1.6 x 10(5) and 3.7 x 10(6) s-1, respectively. In contrast, the spontaneous HO2. elimination reactions of the peroxyl radicals 6 and 7 are very slow, with rate constants of < 1 and approximately 0.5 s-1 as estimated from product analysis. The overall bimolecular decay rate constants of the cyclic dipeptide peroxyl radicals have been determined by pulse radiolysis measurements (2k(6) = 8.6 x 10(8) dm3 mol-1 s-1; 2k(7) = 1.6 x 10(8) dm3 mol-1 s-1; 2k(12/13) = 4.0 X 10(8) dm3 mol-1 s-1). The main products (G values) in the gamma radiolysis of glycine anhydride in N2O/O2-saturated solution at pH 6 are 3-hydroxy-2,5-dioxopiperazine (14) (3.5 x 10(-7) mol J-1), 2,3,5-trioxopiperazine (17) (1.6 X 10(-7) mol J-1), and 2,5-dioxo-2,3,4,5-tetrahydropyrazine (8) (0.4 x 10(-7) mol J-1). The product 8 is in equilibrium with its hydrate 14, which is again in equilibrium with its ring-opened form N-glyoxylyl glycinamide (16). In acidic solutions radical 6 decays essentially bimolecularly, giving equal amounts of 14 (present in an equilibrium mixture of 8, 14, and 16) and 17. In basic solutions 14 becomes the single main product as the OH--induced O2.- elimination reaction becomes much faster than the bimolecular decay. This is in good agreement with the yield of O2.- formation as monitored by its reaction with tetranitromethane under various pH conditions. With alanine anhydride (2), the main reaction under gamma radiolysis conditions even at pH 6 is still the OH--induced O2.- elimination reaction with 3-hydroxy-2,5-dioxo-3,6-dimethylpiperazine (15) as the single main product (G(15) = 4.7 x 10(-7) mol J-1). The major peroxyl radical in the sarcosine anhydride system (12) only decays bimolecularly either by self-termination or by cross-termination with the minor peroxy radical 13 (products at pH 6 in gamma radiolysis: 2,3,5-trioxo-1,4-dimethylpiperazine (20), G = 4.0 x 10(-7) mol J-1; 3-hydroxy-2,5-dioxo-1,4-dimethylpiperazine(21), G = 0.4 x 10(-7) mol J-1; 1-formyl-2,5-dioxo-4-methylpiperazine (22), G = 0.6 x 10(-7) mol J-1; and 2,5-dioxo-1-methylpiperazine (24), G = 0.6 x 10(-7) mol J-1). The O2.-elimination reaction of radical 13 is estimated to have a rate constant of < 5 s-1.
• Thiyl Radicals Abstract Hydrogen Atoms from the ^αC−H Bonds in Model Peptides:  Absolute Rate Constants and Effect of Amino Acid Structure
  作者：Thomas Nauser、Christian Schöneich

  DOI：10.1021/ja0293599

  日期：2003.2.1

  of the homolytic bond dissociation energies (BDEs) only, the (alpha)C-H bonds of peptides and proteins would present suitable targets for hydrogen abstraction by thiyl radicals. However, additional parameters such as polar and conformational effects may control such hydrogen-transfer processes. To evaluate the potential of thiyl radicals for hydrogen abstraction from (alpha)C-H bonds, we provide the

  硫基自由基是生物氧化应激和酶促反应中的重要中间体，例如核糖核苷酸还原酶。仅基于均裂键解离能 (BDE)，肽和蛋白质的 (α)CH 键将成为硫自由基夺氢的合适目标。然而，极性和构象效应等附加参数可能会控制这种氢转移过程。为了评估硫基自由基从 (alpha)CH 键中提取氢的潜力，我们提供了这些与模型肽反应的第一个绝对速率常数。硫基自由基与 (alpha)CH 键反应，速率常数介于 1.7 x 10(3) M(-1) s(-1)（N-乙酰脯氨酸酰胺）和 4 x 10(5) M(-1) s(- 1) (肌氨酸酐)。然而，速率常数与 BDE 的相关性很差。
• Mieden, Oliver J.; Sonntag, Clemens von, Zeitschrift fur Naturforschung, B: Chemical Sciences, 1989, vol. 44, # 8, p. 959 - 974
  作者：Mieden, Oliver J.、Sonntag, Clemens von

  DOI：——

  日期：——