Cbz-Pro-Ala-NH2 is a protected dipeptide derivative used in peptide synthesis. The Cbz (Carbobenzyloxy) group protects the N-terminus of the proline (Pro) residue, preventing it from participating in unwanted reactions during the peptide synthesis process. Ala (Alanine) is the second amino acid in the sequence, and the -NH2 indicates a free amino group at the C-terminus of alanine, allowing for further peptide coupling or modification. This compound is used to introduce proline and alanine into peptides while controlling the reactivity of the functional groups through selective protection.