The α–α helix motif presents key recognition domains in protein–protein and protein–oligonucleotide binding, and is one of the most common super-secondary structures. Herein, we describe the design, synthesis and structural characterisation of an α–α hairpin analogue based on a tetra-coordinated Pd(II) bis-(iminoisoquinoline) complex as a template for the display of two α-helix mimics. This approach is exemplified by the attachment of two biphenyl peptidomimetics to reproduce the side chains of the i and i+4 residues of two helices.

中文翻译：

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超二级结构肽模拟物：α-α发夹类似物的设计和合成

α-α 螺旋基序是蛋白质-蛋白质和蛋白质-寡核苷酸结合的关键识别域，是最常见的超二级结构之一。在此，我们描述了基于四配位 Pd（II）双（亚氨基异喹啉）复合物作为展示两个 α-螺旋模拟物的模板的 α-α 发夹类似物的设计、合成和结构表征。这种方法的例子是连接两个联苯肽模拟物以复制两个螺旋的 i 和 i+4 残基的侧链。