Design of stable β-sheet-based cyclic peptide assemblies assisted by metal coordination: selective homo- and heterodimer formation.

Metal-directed supramolecular construction represents one of the most powerful tools to prepare a large variety of structures and functions. The ability of metals to organize different numbers and types of ligands with a variety of geometries (linear, trigonal, octahedral, etc.) expands the supramolecular synthetic architecture. We describe here the precise construction of homo- and heterodimeric cyclic peptide entities through coordination of a metal (Pd, Au) and to β-sheet-type hydrogen-bonding interactions. The selective coordination properties of the appropriate metal allow control over the cross-strand interaction between the two-peptide strands.