New Open-Chain and Cyclic Tetrapeptides, Consisting of<i>α</i>-,<i>β</i><sup>2</sup>-, and<i>β</i><sup>3</sup>-Amino-Acid Residues, as Somatostatin Mimics - A Survey
作者:Dieter Seebach、Estelle Dubost、Raveendra I. Mathad、Bernhard Jaun、Michael Limbach、Markus Löweneck、Oliver Flögel、James Gardiner、Stefania Capone、Albert K. Beck、Hans Widmer、Daniel Langenegger、Dominique Monna、Daniel Hoyer
DOI:10.1002/hlca.200890190
日期:2008.9
incorporation of a β2-amino-acid residue should lead to mimics of ‘α-peptidic β-turns’ (cf.A, B, C). It is also known that short-chain mixed β/α-peptides with appropriate side chains can be used to mimic interactions between α-peptidic hairpin turns and G protein-coupled receptors. Based on these facts, we have now prepared a number of cyclic and open-chain tetrapeptides, 7–20, consisting of α-, β2-, and β3-amino-acid
环- β -tetrapeptides已知采用一种构象与溶液中的分子内跨环氢键。这种结构的分析揭示了的那掺入β 2氨基酸残基应导致的“模拟物α -peptidic β -turns”(参见A,B,C)。还已知具有适当侧链的短链混合的β / α-肽可用于模拟α-肽发夹转角与G蛋白偶联受体之间的相互作用。基于这些事实,我们现在已经准备了一些循环和开链的四肽,7 - 20,由α - ,β 2 -和β 3 -氨基-酸残基,其承受的Trp和Lys的侧链,并且具有主链结构,使得它们应当能够在其亲和力模拟促生长素抑制素对人SRIF受体(HSST的1 –5)。通过Fmoc策略通过固相偶联制备所有肽。对于环肽,采用了三维正交方法(方案3),获得了最大的成功。通过高分辨率质谱,NMR和CD光谱对新化合物进行表征,在五种情况下,通过完整的NMR溶液结构测定(在MeOH或H 2 O中,图4进行表征)。)。通过与[