Used in bioconjugation processes, particularly in the synthesis of antibody-drug conjugates (ADCs). Acts as an activated linker that enables the attachment of payloads to monoclonal antibodies through thiol groups. The disulfide bond provides a cleavable linkage, allowing for controlled release of the drug inside target cells, especially in cancer therapy. Its nitrophenyl group enhances leaving group ability, improving conjugation efficiency under mild conditions. Commonly employed in pharmaceutical development for targeted drug delivery systems.