Integrin Ligands with α/β‐Hybrid Peptide Structure: Design,Bioactivity, and Conformational Aspects

Integrins are cell surface receptors for proteins of the extracellular matrix and plasma‐borne adhesive proteins. Their involvement in diverse pathologies prompted medicinal chemists to develop small‐molecule antagonists, and very often such molecules are peptidomimetics designed on the basis of the short native ligand‐integrin recognition motifs. This review deals with peptidomimetic integrin ligands composed of α‐ and β‐amino acids. The roles exerted by the β‐amino acid components are discussed in terms of biological activity, bioavailability, and selectivity. Special attention is paid to the synthetic accessibility and efficiency of conformationally constrained heterocyclic scaffolds incorporating α/β‐amino acid span.