Z-Ile-ONp is commonly used in peptide synthesis as a protected amino acid derivative. It serves as a key intermediate in the formation of peptide bonds, particularly in solid-phase peptide synthesis (SPPS). The compound is utilized to introduce isoleucine into peptide chains while protecting the amino group, ensuring selective reactivity during the synthesis process. Its application is critical in the production of custom peptides for research in biochemistry, pharmacology, and drug development. Additionally, Z-Ile-ONp is employed in the study of enzyme mechanisms and protein interactions, providing insights into biological processes and aiding in the design of therapeutic agents.