Boc-Val-Cit-PABA is primarily used in the development of antibody-drug conjugates (ADCs), which are a class of targeted cancer therapies. The compound serves as a linker between the cytotoxic drug and the antibody, enabling precise delivery of the drug to cancer cells. The valine-citrulline (Val-Cit) dipeptide sequence is specifically designed to be cleaved by cathepsin B, an enzyme that is highly active in the lysosomes of cancer cells. This selective cleavage ensures that the cytotoxic payload is released predominantly within the tumor, minimizing damage to healthy tissues. The Boc (tert-butoxycarbonyl) group acts as a protective group during synthesis, ensuring the stability of the compound until it reaches its target. This makes Boc-Val-Cit-PABA a critical component in enhancing the efficacy and safety of ADCs in cancer treatment.