氢键连接的环状组装体中的二硫键交换：通过双重动态化学进行的立体化学自选择。

Disulfide exchange in hydrogen-bonded cyclic assemblies: stereochemical self-selection by double dynamic chemistry.

作者信息

ten Cate A Tessa, Dankers Patricia Y W, Sijbesma Rint P, Meijer E W

机构信息

Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, Post Office Box 513, 5600 MB Eindhoven, The Netherlands.

出版信息

J Org Chem. 2005 Jul 22;70(15):5799-803. doi: 10.1021/jo0501238.

DOI:10.1021/jo0501238

PMID:16018671

Abstract

Stereoselective cyclization of cystine-based bifunctional 2-ureido-4[1H]-pyrimidinone derivatives in CDCl(3) solutions was demonstrated by (1)H NMR spectroscopy. Thiolate-catalyzed disulfide exchange in solution led to the equilibration of different diastereomers of 1. At low concentrations, where formation of cyclic assemblies is the dominant mode of association, the molecules act as their own template. At these concentrations the meso diastereomer is formed preferentially, indicating a higher stability of its cyclic assemblies under the applied conditions, in comparison to the other diastereomers.

摘要

通过¹H NMR光谱证实了基于胱氨酸的双功能2-脲基-4[1H]-嘧啶酮衍生物在CDCl₃溶液中的立体选择性环化。溶液中硫醇盐催化的二硫键交换导致1的不同非对映异构体达到平衡。在低浓度下，形成环状聚集体是主要的缔合模式，分子充当自身的模板。在这些浓度下，内消旋非对映异构体优先形成，表明与其他非对映异构体相比，其环状聚集体在应用条件下具有更高的稳定性。