Sulfane Decreases the Nucleophilic Reactivity of Zinc Thiolates: Implications for Biological Reactive Sulfur Species
Sulfane Decreases the Nucleophilic Reactivity of Zinc Thiolates: Implications for Biological Reactive Sulfur Species
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硫烷降低硫醇锌的亲核反应性：对生物反应性硫物质的影响
DOI：
10.1021/jacs.2c07380
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发表时间：
2022
影响因子：
15
通讯作者：
Tsui, Emily Y.
中科院分区：
文献类型：
--
作者：
Seo, W.T. Michael;Ballesteros, Moises;Tsui, Emily Y.
研究了由[N3 S2]配体支持的二硫代锌络合物作为锌介导的硫醇盐-二硫化物交换的模型，从而能够分离锌结合的混合二硫化物中间体。该锌-二硫化物复合物的溶液相表征表明锌中心和二硫化物部分之间的相互作用，导致随后反应的S-S键活化。通过先前制备的锌四硫基络合物的二硫键交换的该反应的比较表明，硫烷硫（SO）作为一种有效的硫醇盐捕集剂，即，多硫化物阴离子比硫醇盐碱性低得多。与母体硫醇盐阴离子相比，所得的多硫化物阴离子也表现出降低的亲核性。烷基化动力学之间的比较二硫代锌和锌四硫代配合物表明衰减锌结合硫醇亲核性由硫烷。这些结果表明锌、硫烷和硫醇/硫醇盐反应性之间的一般相互作用可以显著影响生物氧化还原过程。
A zinc dithiolate complex supported by a [N3S2] ligand was studied as a model for zinc-mediated thiolate-disulfide exchange, enabling isolation of a zinc-bound mixed-disulfide intermediate. Solution-phase characterization of this zinc-disulfide complex indicates an interaction between the zinc center and the disulfide moiety that results in activation of the S–S bond for subsequent reactions. Comparison of this reaction with disulfide exchange by a previously prepared zinc tetrasulfanido complex demonstrates that sulfane sulfur (S0) acts as an efficient thiolate trapping agent, that is, polysulfanide anions are much less basic than thiolates. The resulting polysulfanide anions also exhibit decreased nucleophilicity compared to the parent thiolate anions. Alkylation kinetics comparisons between the zinc dithiolate and zinc tetrasulfanido complexes indicate attenuation of zinc-bound thiolate nucleophilicity by sulfane. These results suggest a general interplay between zinc, sulfane, and thiol/thiolate reactivity that can significantly impact biological redox processes.