Visible-light photoredox-catalyzed desulfurization of thiol- and disulfide-containing amino acids and small peptides
Visible-light photoredox-catalyzed desulfurization of thiol- and disulfide-containing amino acids and small peptides
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DOI：
10.1002/psc.3016
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发表时间：
2017-07-01
影响因子：
2.1
通讯作者：
Reiser, Oliver
中科院分区：
文献类型：
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作者：
Lee, Myungmo;Neukirchen, Saskia;Reiser, Oliver
在可见光、光催化剂Ir(Df(CF3)ppy)(2)(DTB-bpy)PF6和亚磷酸三乙酯两相反应条件下，建立了一种可扩展的半胱氨酸脱硫法。催化剂的负载量可低至0.01mol%，在操作过程中可有效脱除(0.3ppm)，从而高产率地产生相应的脱硫物。这种方法也适用于胱氨酸、青霉胺和还原和氧化的谷胱甘肽。该反应对pH敏感，半胱氨酸衍生物和谷胱甘肽的最佳pH值分别为6.5和7.0。此外，在一个含有半胱氨酸和蛋氨酸的十肽的脱硫过程中，观察到这两个含硫残基同时氧化成二硫化物和亚硫醚。因此，虽然目前的方案允许简单的硫醇直接可见光介导的脱硫，使用非常低的催化剂负载量和经济高效的三烷基亚磷酸酯作为硫基自由基捕捉剂，但其在复杂底物中的应用需要仔细验证。版权所有(C)2017欧洲肽协会和John Wiley&Sons，Ltd.
A scalable protocol for the desulfurization of cysteine by using visible light, the photocatalyst Ir(dF(CF3)ppy)(2)(dtb-bpy)PF6 and triethylphosphite under biphasic reaction conditions has been developed. The loading of the catalyst can be as low as 0.01mol%, which can be efficiently removed during the workup (0.3ppm), giving rise to the corresponding desulfurized product in high yields. This method has been applied also to cystine, penicillamine, and reduced and oxidized glutathione. The desulfurization has been found to be pH sensitive, with an optimal pH value of 6.5 and 7.0 for the cysteine derivatives and glutathione, respectively. In addition, during the desulfurization of a decapeptide containing cysteine and methionine, concurrent oxidation of the two sulfur-containing residues to disulfide and sulfoxide has been observed. Therefore, whereas the presented protocol allows a straightforward visible light-mediated desulfurization of simple thiols by using very low catalyst loading and a cost-effective trialkylphosphite as thiyl radical trapping agent, its application to complex substrates needs to be carefully validated. Copyright (c) 2017 European Peptide Society and John Wiley & Sons, Ltd.