Single residue control of the helical topology of β-peptides is a contemporary challenge in foldamer science. We present the conformational preferences of oligomers of trans-2-aminocyclobutanecarboxylic acid (tACBC), in which a central residue has been replaced by a single N-aminoazetidine-2-carboxylic acid (AAzC) moiety. The latter has such a strong demand for local 8-helical conformers that the usual 12-helix secondary structure of a tACBC octamer is switched to a fully 8-helical conformation as a result of the single residue substitution.

中文翻译：

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β肽的战略性C到N替换：螺旋折叠的原子水平控制。

对β-肽的螺旋形拓扑的单残基控制是折叠科学中的当代挑战。我们提出反式-2-氨基环丁烷羧酸（t ACBC）的低聚物的构象偏好，其中中心残基已被单个N-氨基氮杂环丁烷-2-羧酸（AAzC）部分取代。后者对局部8-螺旋构象异构体有如此强烈的需求，以至于t ACBC八聚体的通常的12-螺旋二级结构由于单个残基取代而转变为完全8-螺旋构象。