Stereoselective Synthesis of Tricyclic Diproline Analogues that Mimic a PPII Helix: Structural Consequences of Ring-Size Variation
作者:Arne Soicke、Cédric Reuter、Matthias Winter、Jörg-Martin Neudörfl、Nils Schlörer、Ronald Kühne、Hans-Günther Schmalz
DOI:10.1002/ejoc.201402737
日期:2014.10
Polycyclic proline-derived scaffolds (ProMs) have recently demonstrated their value as conformationally defined dipeptide analogs for the modular construction of secondary structure mimetics, specifically interfering with PPII helix-mediated protein–protein interactions. We disclose the stereoselective synthesis of two new tricyclic amino acid scaffolds (ProM-4 and ProM-8) that differ from the first generation
多环脯氨酸衍生支架 (ProMs) 最近证明了它们作为构象定义的二肽类似物的价值,用于二级结构模拟物的模块化构建,特别是干扰 PPII 螺旋介导的蛋白质 - 蛋白质相互作用。我们公开了两种新的三环氨基酸支架(ProM-4 和 ProM-8)的立体选择性合成,它们与第一代支架 ProM-1 的不同在于环 A 的大小。三个同源支架的构象偏好和细微的结构差异是通过 X 射线晶体学、计算计算和核磁共振光谱分析。N-叔丁氧基羰基(Boc)-3-(1-丙烯基)氮杂环丁烷-2-羧酸由L-天冬氨酸通过β-内酰胺中间体制备。相应的基于哌啶的结构单元外消旋-N-Boc-3-乙烯基哌啶酸是通过铜催化乙烯基-MgBr 的 1,4-加成到 N-Boc-2,3-脱氢哌啶酸甲酯而合成的。目标分子是通过相应的 A 环结构单元与顺式 5-乙烯基脯氨酸叔丁酯的肽偶联和随后的闭环复分解来制备的。在叔丁酯的存在下,使用三氟乙酸在