通过非手性α-氨基异丁酸(Aib),ArSO 2-(Aib)5 -OMe(Ar =对甲苯基,对溴苯基和对甲氧基苯基)的同五肽的分子构象,堆积结构和分子间相互作用单晶X射线衍射分析。将肽折叠成3个10螺旋构象,该构象由两个或三个连续的III型或III'型十原子分子内氢键合的β-转角组成。在打包模式下,左手(M)和右手(P)3 10-螺旋分子形成具有头尾型分子间氢键的线性网络结构。根据功能基团或取代基的不同,获得了两种由同手性序列(⋯ M ⋯ M ⋯ M ⋯或⋯ P ⋯ P ⋯ P ⋯)和杂手性序列(⋯ M ⋯ P ⋯ M ⋯ P consisting)组成的网络结构。肽。有趣的是,当使用不同的结晶介质时,具有对甲苯基的肽1a结晶不同。
Unexpected alkoxyl migration in the reaction of silyl ketene acetals with p-toluenesulfonyl azide
作者:Yong Xu、Shizheng Zhu
DOI:10.1016/s0040-4020(01)00283-6
日期:2001.4
The reaction of p-toluenesulfonylazides with several silyl ketene acetals has been investigated. 1-Trimethylsilyloxy-ethylene reacted with TsN3 to give a good yield of N-p-toluenesulfonyl substituted glycinates exclusively. However, during the reaction of 1-trimethylsilyloxy-propene with TsN3, an unexpected alkoxyl migration occurred to give N-acylsulfonyl amides; other products, N-p-toluenesulfonyl
Synthesis of N-alkyl-Cα,α-dimethylglycine derivatives
作者:Luís S. Monteiro、Silvia M.M.A. Pereira-Lima、Sofia Pereira、João N. Machado
DOI:10.3998/ark.5550190.p008.622
日期:——
Foundation for Science and Technology (FCT) – Portugal and Fundo Europeu de Desenvolvimento Regional (FEDER) for financial support to Chemistry Centre of University of Minho. The NMR spectrometer Bruker Avance II+ 400 is part of the National NMR Network and was purchased in the framework of the National Program for Scientific Re-equipment; contract REDE/1517/RMN/2005, with funds from POCI 2010, FEDER
科学技术基金会 (FCT) – 葡萄牙和欧洲发展基金会 (FEDER) 为米尼奥大学化学中心提供财政支持。NMR 波谱仪 Bruker Avance II+ 400 是 National NMR Network 的一部分,是在 National Program for Scientific Re-equipment 的框架内购买的;合同 REDE/1517/RMN/2005,资金来自 POCI 2010、FEDER 和 FCT。
Homochiral and heterochiral associations observed in crystals of ArSO<sub>2</sub>-(Aib)<sub>5</sub>-OMe
The molecular conformations, packing structures and intermolecularinteractions of homopentapeptides from achiral α-aminoisobutyric acid (Aib), ArSO2-(Aib)5-OMe (Ar = p-tolyl, p-bromophenyl and p-methoxyphenyl), have been investigated by single-crystal X-ray diffraction analysis. The peptides were folded in 310-helical conformations consisting of two or three consecutive ten-atom intramolecular hydrogen-bonded
通过非手性α-氨基异丁酸(Aib),ArSO 2-(Aib)5 -OMe(Ar =对甲苯基,对溴苯基和对甲氧基苯基)的同五肽的分子构象,堆积结构和分子间相互作用单晶X射线衍射分析。将肽折叠成3个10螺旋构象,该构象由两个或三个连续的III型或III'型十原子分子内氢键合的β-转角组成。在打包模式下,左手(M)和右手(P)3 10-螺旋分子形成具有头尾型分子间氢键的线性网络结构。根据功能基团或取代基的不同,获得了两种由同手性序列(⋯ M ⋯ M ⋯ M ⋯或⋯ P ⋯ P ⋯ P ⋯)和杂手性序列(⋯ M ⋯ P ⋯ M ⋯ P consisting)组成的网络结构。肽。有趣的是,当使用不同的结晶介质时,具有对甲苯基的肽1a结晶不同。