Synthesis and Structural Analysis of Cyclic Oligomers Consisting of Furanoid and Pyranoid ε-Sugar Amino Acids
作者:Renate M. van Well、Luciana Marinelli、Kees Erkelens、Gijsbert A. van der Marel、Antonio Lavecchia、Herman S. Overkleeft、Jacques H. van Boom、Horst Kessler、Mark Overhand
DOI:10.1002/ejoc.200300031
日期:2003.6
Cyclic oligomers composed of amide-linked furanoid (i.e., 1, 3) and pyranoid (i.e., 2, 4) ϵ-sugar amino acids (SAAs) were prepared by a cyclization/cleavage approach with use of the oxime resin. These cyclic homooligomers were constructed by use of the known N-Boc protected furanoid ϵ-SAA 11 and the novel pyranoid hydroxymethylene homologue 22. Conformational analysis of cyclic trimer 1 by an unrestrained
由酰胺连接的呋喃(即 1, 3)和吡喃(即 2, 4)ε-糖氨基酸 (SAA) 组成的环状低聚物是通过环化/裂解方法使用肟树脂制备的。这些环状同低聚物是通过使用已知的 N-Boc 保护的呋喃 ϵ-SAA 11 和新型吡喃羟基亚甲基同系物 22 构建的。通过无限制的模拟退火技术对环状三聚体 1 的构象分析表明,残基的呋喃环在 I 之间翻转扭曲(北,P = 0°)和包络(南,P = 167°)构象。此外,连接羰基官能团(即C2)的侧链被证明是刚性的,而其他侧链(C7)在构象上是柔性的。对于三聚体 2 中的吡喃 ϵ-SAA II 残基的侧链,观察到类似的构象行为,但吡喃环椅构象在计算过程中保持稳定。这些构象细节可能对未来基于 SAA 的人工受体或肽模拟物的设计具有重要意义。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)