Widely used in organic synthesis, particularly as a derivatizing agent for amines and amino acids. It reacts selectively with primary and secondary amines to form sulfonamides, which are useful intermediates in pharmaceutical manufacturing and analytical chemistry. Commonly employed in the preparation of fluorescent probes and tags due to the naphthalene ring’s inherent fluorescence properties. Also serves as a precursor in the synthesis of dyes, agrochemicals, and certain protease inhibitors. Its reactivity makes it valuable in peptide chemistry for protecting group strategies and in the development of enzyme inhibitors where sulfonyl groups enhance binding affinity.