Metal‐Containing Hosts for Selective Recognition of Amino Acids and Their Derivatives

Amino acids and their derivatives are challenging targets for molecular recognition because they combine zwitterionic character, strong solvation, structural similarity, side‐chain diversity, and chirality. Metal‐containing hosts offer distinct advantages for addressing these challenges, as metal centers can enforce preorganization, define cavity geometry, introduce coordination sites, modulate charge distribution, and couple guest binding to optical, electrochemical, or chiroptical responses. This review summarizes discrete metal‐containing host architectures for the recognition of amino acids and their derivatives, with an emphasis on host design and host–guest interactions, in addition to the role of metal centers. The discussion is organized by receptor class, including self‐assembled coordination cages, metal‐containing cavitands, metallacrowns, metallocryptands, porphyrin‐based receptors, and open‐chain metal‐containing receptors. Across these systems, recognition is achieved through different combinations of metal coordination, hydrogen bonding, electrostatic attraction, hydrophobic effects, steric fit, and chiral induction. The review also highlights current limitations, including modest selectivity in many systems, reliance on protected or derivatized amino acids, and incomplete structural characterization of binding modes. Finally, emerging sensing and functional materials based on amino acid recognition are discussed, suggesting that metal‐assisted amino acid recognition is moving beyond classical equilibrium binding toward analytical and functional applications.