Used in peptide synthesis as a building block, particularly in solid-phase peptide synthesis (SPPS). Fmoc-Ser(Bzl)-OH features the Fmoc (9-fluorenylmethyloxycarbonyl) group protecting the alpha-amino group of L-serine and the Bzl (benzyl) group protecting the side chain hydroxyl group, preventing unwanted reactions during the synthesis process. The Fmoc group is removed under mild basic conditions (e.g., with piperidine), allowing for the sequential addition of amino acids to form peptides. The Bzl group offers orthogonal protection that can be removed under acidic or hydrogenolytic conditions. Commonly applied in the production of therapeutic peptides, research peptides, and bioactive compounds. Its stability, orthogonality, and ease of deprotection make it a preferred choice in peptide chemistry.