Fmoc-4-chloro-L-phenylalanine is used as a protected amino acid building block in solid-phase peptide synthesis (SPPS) for the preparation of peptides and peptide-based pharmaceuticals.

Its purpose is to introduce the 4-chloro-L-phenylalanine residue into a growing peptide chain while the Fmoc protecting group prevents unwanted reactions during synthesis.

Fmoc-4-chloro-L-phenylalanine is an Fmoc-protected derivative of the non-natural amino acid 4-chloro-L-phenylalanine designed to provide selective amino group protection and facilitate efficient peptide synthesis.