Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96)
Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
致癌物分类
对人类不具有致癌性(未被国际癌症研究机构IARC列名)。
No indication of carcinogenicity to humans (not listed by IARC).
Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma, seizures, apnea, cardiac arrest and death. Chronic inhalation of cyanide causes breathing difficulties, chest pain, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Skin contact with cyanide salts can irritate and produce sores. (L96, L97)
Cyanide poisoning is identified by rapid, deep breathing and shortness of breath, general weakness, giddiness, headaches, vertigo, confusion, convulsions/seizures and eventually loss of consciousness. (L96, L97)
1,1,3,3-四甲基二硅氧烷(TMDS)和聚甲基氢硅氧烷(PMHS)与异丙醇钛(IV)结合使用时,提供了两个方便的系统,可将腈还原为相应的伯胺。通过1 H NMR研究了这两个系统的动力学,结果表明,用PMHS进行还原的速度比用TMDS进行还原的速度更快。在存在Br,CC,NO 2的情况下,这两个钛基体系同时还原芳族和脂肪族腈,OH和环丙基环。在环丙基腈的情况下,观察到由于分子间还原性烷基化反应而形成的仲胺。该结果被用于还原二腈,其通过分子内还原性烷基化反应一步一步导致了氮杂环庚烷,哌啶,吡咯烷和氮杂环丁烷衍生物。
Exploring the Synthetic Applicability of a Cyanobacterium Nitrilase as Catalyst for Nitrile Hydrolysis
作者:Chandrani Mukherjee、Dunming Zhu、Edward R. Biehl、Ling Hua
DOI:10.1002/ejoc.200600699
日期:2006.12
specificity and syntheticapplicability of the nitrilase from cyanobacterium Synechocystis sp. strain PCC 6803 have been examined. This nitrilase catalyzed the hydrolysis of both aromatic and aliphatic nitriles to the corresponding acids in high yields. Furthermore, the stereoselective hydrolysis of phenyl-substituted β-hydroxy nitriles to (S)-enriched β-hydroxy carboxylic acids and selective hydrolysis of α
to afford bicyclic pyridines. Careful screening of nitrile components revealed that a C[triple chemical bond]C triple bond or heteroatom substituents, such as methoxy and methylthio groups, proved to act as the coordinating groups, whereas C==C or C==O doublebonds and amino groups failed to promote cycloaddition. This suggests that coordinating groups with multiple pi-bonds or lone pairs are essential
1-Butyl-3-methylimidazol-2-ylidene Borane: A Readily Available, Liquid N-Heterocyclic Carbene Borane Reagent
作者:Daniel A. Bolt、Dennis P. Curran
DOI:10.1021/acs.joc.7b02730
日期:2017.12.15
1-Butyl-3-methylimidazol-2-ylidene borane has been synthesized directly from two inexpensive commercial reagents: 1-butyl-3-methylimidazolium bromide and sodium borohydride. This NHC-borane reagent is a stable, free-flowing liquid that shows promise for use in radical, ionic, and metal-catalyzed reactions.
A method for the thiolysis of nitriles by applying Lawesson’s reagent and facilitated by the addition of boron trifluoride-diethyl ether complex is reported. The method opens an easy access to primary thioamides. Aromatic, benzylic, and aliphatic nitriles were converted into the corresponding thioamides in high to quantitative yields (even in unfavorable cases, e.g., ortho-substituted benzonitriles). The reaction was performed in 1,2-dimethoxyethane-tetrahydrofuran or toluene-diethyl ether solvent mixtures at 20-50 ËC, and exhibited considerable selectivity in the case of multifunctional nitrile substrates, such as cyanomethyl N-acetylphenylalaninate, benzoylacetonitrile, 4-cyanobenzamide, 4-acetyl-benzonitrile, or pent-3-enenitrile.
Rearrangement of 3-Hydroxyazetidines into 2-Oxazolines
作者:Michele Ruggeri、Amanda W. Dombrowski、Stevan W. Djuric、Ian R. Baxendale
DOI:10.1021/acs.joc.0c00656
日期:2020.6.5
A novel rearrangement sequence of 3-hydroxyazetidines via a Ritter initiated cascade provides highly substituted 2-oxazolines in high yields. The reaction conditions and substrate scope of the transformation have been studied demonstrating the generality of the process. The derived products can also be functionalized in order to undergo further intramolecular cyclization leading to a new class of macrocycle