Boc-4-(4-Pyridyl)-L-β-homoalanine is a protected non-proteinogenic amino acid derivative. Its structure features a β-homoalanine backbone (an alanine homolog with an extra methylene group), a 4-pyridyl side chain at the β-position, and a tert-butoxycarbonyl (Boc) protecting group on the α-amino functionality. This specific combination of a heteroaromatic side chain and an extended backbone makes it a specialized building block. This compound is primarily employed as a key intermediate in the synthesis of peptide mimetics and modified peptides for pharmaceutical research. The pyridyl ring can serve as a hydrogen bond acceptor or a metal-coordinating group, while the β-amino acid structure introduces conformational constraints and enhances metabolic stability compared to natural α-amino acids. It is particularly valuable in constructing peptidomimetics targeting protein-protein interactions or enzymes. As a Boc-protected amino acid, it is compatible with standard solid-phase peptide synthesis (SPPS) protocols using Fmoc chemistry, where the Boc group is stable. Its main application lies in medicinal chemistry for developing novel therapeutic agents, including protease inhibitors or receptor modulators.