Used in solid-phase peptide synthesis to incorporate threonine residues with orthogonal protection. The Fmoc group allows for temporary α-amino protection that is removed under mild basic conditions, while the TBDMS group protects the threonine side chain hydroxyl from unwanted reactions during synthesis. This dual protection strategy is especially useful in the preparation of complex peptides and glycopeptides where selective deprotection and coupling steps are required. The stability of the TBDMS ether under Fmoc removal conditions makes it compatible with stepwise assembly on resin. Commonly used in research settings for synthesizing bioactive peptides, enzyme substrates, and peptide-based probes.