Used in peptide synthesis, particularly in solid-phase peptide synthesis (SPPS), to incorporate iodinated tyrosine residues into peptides. The Fmoc group protects the amino group during synthesis, allowing selective deprotection and elongation of the peptide chain. The iodinated tyrosine is valuable in studies involving radioiodination for imaging or therapeutic purposes, such as in positron emission tomography (PET) or targeted radiotherapy. Additionally, it aids in research on protein-protein interactions, enzyme mechanisms, and structural studies due to the heavy iodine atoms, which can enhance X-ray crystallography resolution. Its application is critical in developing peptide-based drugs and biochemical probes.