Z-D-Ornithine is a protected derivative of the non-proteinogenic amino acid D-ornithine. Its chemical structure features a benzyloxycarbonyl (Z or Cbz) group protecting the alpha-amino group, which is a standard strategy in peptide synthesis to prevent unwanted side reactions. The compound is characterized by its chirality (D-configuration) and the presence of a free carboxylic acid group and a side-chain amino group. This compound serves as a crucial chiral building block in the synthesis of peptides and peptidomimetics. The D-ornithine residue is of particular interest in the development of bioactive peptides, antimicrobial peptides (AMPs), and enzyme inhibitors due to its ability to influence peptide conformation, stability, and biological activity. The Z-protecting group is stable under typical peptide coupling conditions but can be readily removed under mild hydrogenolytic conditions, making it a versatile intermediate in solid-phase and solution-phase peptide synthesis. As a specialty amino acid derivative, it is primarily used in pharmaceutical research for constructing novel peptide-based drug candidates. Its applications extend to biochemical studies exploring protein-protein interactions and substrate specificity of enzymes.