Synthesis and High-Resolution NMR Structure of a β3-Octapeptide with and without a Tether Introduced by Olefin Metathesis
作者:Marc-Olivier Ebert、James Gardiner、Steven Ballet、Andrewâ
D. Abell、Dieter Seebach
DOI:10.1002/hlca.200900311
日期:2009.12
in CD3OH of the two β3‐octapeptide derivatives without (i.e., 1) and with tether (i.e., 4; Tables 1–6, and Figs. 4 and 5) provided structures of a degree of precision (by including the complete set of side chain–side chain and side chain–backbone NOEs) which is unrivaled in β‐peptide NMR‐solution‐structure determination. Comparison of the two structures (Fig. 5) reveals small differences in side‐chain
之间桥接(我) -和(我3)位上的β 3 -肽具有适当长度的系链,是为了防止相应的3 14螺旋从展开(图1)。所述β 3 -肽H- β 3 hVal- β 3 hLys- β 3 hSer(全部) - β 3 hPhe- β 3 hGlu- β 3 hSer(全部) - β 3 hTyr- β 3 HILE-OH(1 ;具有烯丙基化的β在3-位和6-位hSer残基),和三个系绳β -肽2 - 4(与1通过闭环复分解)已合成(固相耦合,Fmoc策略,在氯三苯甲基树脂;方案)。拴系的比较分析CD β -肽4和它的非栓系类似物1表明螺旋倾向是由(CH显著增强(三倍CD强度)2)4之间的接头β 3 hSer侧链(图2) 。这个结论是基于这样的前提,即负数的强度棉附近的CD光谱215nm处效果β 3 -肽代表了“螺旋含量”的量度。NMR分析在CD 3两者的OH β 3而不-octapeptide衍生物(即,1),并用系绳(即,4