Conformational Effects through Hydrogen Bonding in a Constrained γ-Peptide Template: From Intraresidue Seven-Membered Rings to a Gel-Forming Sheet Structure
作者:Hawraà Awada、Claire M. Grison、Florence Charnay-Pouget、Jean-Pierre Baltaze、François Brisset、Régis Guillot、Sylvie Robin、Ali Hachem、Nada Jaber、Daoud Naoufal、Ogaritte Yazbeck、David J. Aitken
DOI:10.1021/acs.joc.7b00494
日期:2017.5.5
conformers, including ribbonlike structures pleated around a rarely observed series of intramolecular seven-membered hydrogen bonds. In more concentrated solutions, these interactions defer to an organized supramolecular assembly, leading to thermoreversible organogel formation notably for the tripeptide, which produced fibrillar xerogels. In the solid state, the dipeptide adopted a fully extended conformation
一系列三个顺式的短寡聚物(二,三和四聚物)制备了具有环丁烷环约束性的γ-氨基酸-2-(氨基甲基)环丁烷羧酸,并通过光谱和分子模拟研究了它们的构象行为。在稀溶液中,这些肽显示出许多低能构象体,包括在很少观察到的一系列分子内七元氢键周围折叠的带状结构。在更浓缩的溶液中,这些相互作用会导致有序的超分子组装,导致热可逆的有机凝胶形成,尤其是三肽的热可逆性有机凝胶的形成,从而产生原纤维干凝胶。在固态状态下,二肽采用完全延伸的构象,其特征是分子间以氢键键合的分子以反平行的片状排列方式堆叠的一维网络。