Used in peptide synthesis as a protected form of 2,4-diaminobutyric acid (Dab), with Fmoc on the α-amino group and Z on the side-chain amino group. It helps in preventing unwanted side reactions during the formation of peptide bonds. Commonly applied in solid-phase peptide synthesis (SPPS) to ensure selective deprotection and coupling steps. Its stability under acidic conditions makes it suitable for complex peptide chain assembly. Also utilized in the development of pharmaceuticals and bioactive peptides, where precise amino acid sequence control is critical.