Boc-3-(3-pyridyl)-L-alanine is a protected amino acid derivative featuring a pyridyl side chain and an N-terminal tert-butoxycarbonyl (Boc) protecting group. It is a white to off-white crystalline powder with a molecular formula of C13H18N2O4. This compound is a non-natural, chiral amino acid building block where the L-configuration is specified. Its primary application is in the field of peptide synthesis and medicinal chemistry as a key intermediate. The Boc group is a standard protecting group for amines in solid-phase peptide synthesis (SPPS), allowing for orthogonal deprotection strategies. The incorporation of the 3-pyridyl moiety introduces a heteroaromatic ring that can serve as a hydrogen bond acceptor or participate in π-stacking interactions, which is valuable for modulating the physicochemical properties, bioavailability, and target binding affinity of peptide-based drug candidates. It is specifically used in the research and development of novel therapeutic peptides. This building block is commercially available from fine chemical suppliers specializing in amino acids and peptide synthesis reagents. It requires storage in a cool, dry place and should be handled with standard laboratory safety precautions, including the use of personal protective equipment.