Used in pharmaceutical synthesis as a protected thiol-containing linker, enabling controlled conjugation in drug delivery systems and bioconjugation. Its oligoethylene glycol spacer provides water solubility and flexibility, making it ideal for constructing prodrugs, PEGylated compounds, and targeted therapeutics. The tert-butyl carbamate (Boc) group ensures stable protection of the amine during reactions, while the thiol end allows for selective coupling to proteins, peptides, or nanoparticles. Commonly applied in the development of antibody-drug conjugates (ADCs) and diagnostic probes where precise molecular attachment is critical.