Used as a protected thiol-containing building block in organic synthesis, particularly in the development of pharmaceuticals and bioactive molecules. The tert-butyl carbamate (Boc) group provides amine protection, while the thiol moiety can be deprotected and utilized for conjugation, such as in the formation of disulfide bonds or thioether linkages. Commonly employed in peptide chemistry and the synthesis of cysteine analogs. Also serves as an intermediate in the preparation of protease inhibitors and other enzyme modulators where controlled reactivity and selective deprotection are required.