Used primarily in peptide synthesis, it serves as a protected form of cysteine, ensuring selective reactions during the assembly of peptide chains. The Trt (trityl) group protects the thiol side chain, preventing unwanted side reactions, while the OtBu (tert-butyl ester) group protects the carboxyl group. This compound is particularly valuable in solid-phase peptide synthesis (SPPS), where controlled deprotection steps are crucial. It is also employed in the production of complex peptides and proteins, especially those requiring precise cysteine incorporation for disulfide bond formation. Its stability and compatibility with various coupling reagents make it a reliable choice in pharmaceutical research and biotechnology applications.