?2- and ?3-Peptides with Proteinaceous Side Chains: Synthesis and solution structures of constitutional isomers, a novel helical secondary structure and the influence of solvation and hydrophobic interactions on folding
作者:Dieter Seebach、Stefan Abele、Karl Gademann、Gilles Guichard、Tobias Hintermann、Bernhard Jaun、Jennifer L. Matthews、J�rg V. Schreiber、Lukas Oberer、Ulrich Hommel、Hans Widmer
DOI:10.1002/hlca.19980810513
日期:——
the previously prepared β-peptides (35–39) showed NH/ND exchange rates (in MeOH at room temperature) with τ1/2 values of up to 60 days, unrivalled by short chain α-peptides. All β-peptides 1–7 were designed to be able to attain the previously described 31-helical structure (Figs. 1 and 2). CD Measurements (Fig. 4), indicating a new secondary structure of certain β-peptides constructed of β2- and β3-amino
对映体纯β-氨基酸为Ala,Val取代,和Leu的在2-或3-位上的侧链的衍生物(β 2 -和β 3 -氨基酸,RESP),以及与在这两个取代基2-位和3-位(β 2,3 -氨基酸的,像-构型)已经制备(化合物8 - 17)和结合(通过逐步合成和片段耦合,中间体24 - 34)到β-化十六- , β-庚肽和β-十二肽(1 – 17)。新的和一些先前制备的β肽(35 – 39)显示了NH / ND交换速率(室温下在MeOH中),其τ1 /2值长达60天,这是短链α肽无法比拟的。所有的β肽1至7被设计为能够获得先前描述的3 1螺旋结构(图1和2)。CD测量(图4),表明β的构建某些β肽的新的二级结构2 -和β 3 -氨基酸,通过详细的NMR溶液结构分析确认:一个β 2 -heptapeptide(2C)和β 2,3- -hexapeptide(图7c),由于具有3 1螺旋结构(图6和7),而到β