Water-soluble β-strand peptidomimetics.

Mediation of protein-protein interactions with molecules that bind strongly and selectively to one of the partners at the protein interface is a promising therapeutic strategy for myriad diseases. One such approach is the rational design of non-peptidic scaffolds that reproduce the display of amino acid side chains from one face of a secondary structural element. We have previously disclosed proof-of principle syntheses of β-strand mimetics composed of alternating (hetero)aromatic and cyclic urea units, conformationally preorganised through dipolar repulsion in organic solvents, that are in good agreement with the i, i + 2, and i + 4 side-chain vectors of a canonical strand. Here we demonstrate sequence diversity of the approach through the incorporation of hydrophobic and hydrophilic side-chain mimics via an improved synthetic route. The scaffold is conformationally preorganised for target binding in aqueous media including buffer, is readily soluble, and thus is suitable for elaboration and deployment against specific protein targets.