Cbz-D-Ala-OH is a protected D-amino acid derivative, specifically the N-carbobenzyloxy (Cbz) protected form of D-alanine. It is a white to off-white crystalline powder with a molecular formula of C11H13NO4 and a molecular weight of 223.23 g/mol. The Cbz group serves as a common amine-protecting group in peptide synthesis, which can be removed under mild hydrogenolytic conditions. This compound is a fundamental building block in the synthesis of peptides and peptidomimetics, particularly those incorporating the non-natural D-alanine enantiomer. It is widely used in pharmaceutical research for the preparation of novel therapeutic peptides, including antimicrobial peptides and enzyme inhibitors. Its primary application lies in solid-phase peptide synthesis (SPPS) and solution-phase peptide chemistry as a key intermediate. As a chiral synthon, it is crucial for introducing structural diversity and modulating the biological activity, stability, and pharmacokinetic properties of peptide-based drug candidates. It is a standard reagent in laboratories focused on medicinal chemistry and peptide science.