Metal ions offer vast opportunities for the structural control at the molecular scale; exploiting their different coordinative properties 1, researchers can create complex assemblies of great beauty and unique properties, on par with the extraordinary structural and functional complexity displayed by peptides 2. Bridging the architectural potential of coordination chemistry with the structural predictability of peptide scaffolds would allow greater complexity in (supra)molecular designs by combining well-established peptide engineering concepts and tools with the supramolecular organization mediated by metal ions 3.

Helicates are discrete metal complexes in which one or more organic ligands coil around—and coordinate—two or more metal ions. Helicates display helical chirality, according to the orientation in which the ligands twist around the axis defined by the metal centers
4. Besides their fundamental interest in supramolecular chemistry, helicates have also shown exciting properties as antifreeze agents 5, as inhibitors of amyloid aggregation 6, as well as G quadruplex and three-way DNA binding properties that result in promising antimicrobial and antitumoral activities 7. Therefore, as a challenging and relevant model system to demonstrate the potential of peptide platforms for engineering metallo-supramolecular entities, we decided to approach the stereoselective synthesis of peptide helicates

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