2-(γ-hydroxy-(E)-cinnamyl)-4,5-dimethylthiazole | 133984-11-9

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 唑类
• 英文名称: 2-(γ-hydroxy-(E)-cinnamyl)-4,5-dimethylthiazole
• CAS: 133984-11-9
• 化学式: C₁₄H₁₅NOS
• 分子量: 245.345
• InChiKey: LNHWAIHYGLDSAI-CMDGGOBGSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  3.51
• 重原子数：
  17.0
• 可旋转键数：
  3.0
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.21
• 拓扑面积：
  33.12
• 氢给体数：
  1.0
• 氢受体数：
  3.0

反应信息

• 作为反应物：
  描述：

  3,4-二氢-2H-吡喃 、 2-(γ-hydroxy-(E)-cinnamyl)-4,5-dimethylthiazole 在 对甲苯磺酸 作用下， 以 四氢呋喃 为溶剂， 反应 4.0h， 以67.6%的产率得到2-<γ-<(tetrahydro-2H-pyran-2-yl)oxy>-(E)-cinnamyl>-4,5-dimethylthiazole
  参考文献：
  名称：

  Direct observation of the kinetic fate of a thiamin diphosphate bound enamine intermediate on brewers' yeast pyruvate decarboxylase. Kinetic and regiospecific consequences of allosteric activation

  摘要：

  The interaction of (E)-2-oxo-4-p-tolyl-3-butenoic acid with brewer's yeast pyruvate decarboxylase was examined by kinetic and absorption spectroscopic means. The compound undergoes catalytic turnover, leading to a thiamin diphosphate bound enamine intermediate that can be protonated at both allylic positions leading to p-methylcinnamaldehyde and p-methyldihydrocinnamic acid in a ratio of 1:3 in the absence of and 3:2 in the presence of the allosteric activator pyruyamide. The compound is also a weak but irreversible inactivator of the enzyme, and according to colorimetric titration of the enzyme prior to and subsequent to inactivation, it reacts with a Cys side chain with a 1:1 stoichiometry; i.e., one Cys/subunit is being modified. The data are consistent with partitioning of the 2-(p-methyldihydrocinnamoyl)thiamin diphosphate between nonenzymic hydrolysis to the free p-methyldihydrocinnamic acid and transfer to a Cys on the enzyme forming a p-methyldihydrocinnamoyl thiol ester. The latter at the pH used is quite stable, and hence inactivates the enzyme. An enzyme-bound enamine intermediate can be detected at 440 nm, and its rates of formation and disappearance can be conveniently monitored. A thiazolium model for a precursor to such an enamine, 2-[gamma-[tetrahydro-2H-pyran-2-yl)oxyl-(E)-cinnamyl)-3,4,5-trimethylthiazolium ion, when treated with (TMS)2NNa in Me2SO gave an absorbance with identical lambda-max, confirming the assignment of the absorbance observed from such conjugated 2-keto acids to the thiamin-bound enamine structure. Finally, the allosteric activator pyruyamide was found to enhance the rate of enamine formation by as much as 50-fold, both the rates of formation and conversion to product of the enamine being affected by the allosteric regulation. On the basis of data provided, (E)-2-oxo-4-p-tolyl-3-butenoic acid is proposed as a convenient active-site titrant for pyruvate decarboxylase.

  DOI：

  10.1021/ja00015a044
• 作为产物：
  描述：

  4,5-二甲基噻唑 、 反式肉桂醛 在 正丁基锂 作用下， 生成 2-(γ-hydroxy-(E)-cinnamyl)-4,5-dimethylthiazole
  参考文献：
  名称：

  Direct observation of the kinetic fate of a thiamin diphosphate bound enamine intermediate on brewers' yeast pyruvate decarboxylase. Kinetic and regiospecific consequences of allosteric activation

  摘要：

  The interaction of (E)-2-oxo-4-p-tolyl-3-butenoic acid with brewer's yeast pyruvate decarboxylase was examined by kinetic and absorption spectroscopic means. The compound undergoes catalytic turnover, leading to a thiamin diphosphate bound enamine intermediate that can be protonated at both allylic positions leading to p-methylcinnamaldehyde and p-methyldihydrocinnamic acid in a ratio of 1:3 in the absence of and 3:2 in the presence of the allosteric activator pyruyamide. The compound is also a weak but irreversible inactivator of the enzyme, and according to colorimetric titration of the enzyme prior to and subsequent to inactivation, it reacts with a Cys side chain with a 1:1 stoichiometry; i.e., one Cys/subunit is being modified. The data are consistent with partitioning of the 2-(p-methyldihydrocinnamoyl)thiamin diphosphate between nonenzymic hydrolysis to the free p-methyldihydrocinnamic acid and transfer to a Cys on the enzyme forming a p-methyldihydrocinnamoyl thiol ester. The latter at the pH used is quite stable, and hence inactivates the enzyme. An enzyme-bound enamine intermediate can be detected at 440 nm, and its rates of formation and disappearance can be conveniently monitored. A thiazolium model for a precursor to such an enamine, 2-[gamma-[tetrahydro-2H-pyran-2-yl)oxyl-(E)-cinnamyl)-3,4,5-trimethylthiazolium ion, when treated with (TMS)2NNa in Me2SO gave an absorbance with identical lambda-max, confirming the assignment of the absorbance observed from such conjugated 2-keto acids to the thiamin-bound enamine structure. Finally, the allosteric activator pyruyamide was found to enhance the rate of enamine formation by as much as 50-fold, both the rates of formation and conversion to product of the enamine being affected by the allosteric regulation. On the basis of data provided, (E)-2-oxo-4-p-tolyl-3-butenoic acid is proposed as a convenient active-site titrant for pyruvate decarboxylase.

  DOI：

  10.1021/ja00015a044