Used as a key intermediate in the synthesis of fluorescent dyes and optical brighteners due to its reactive sulfonyl chloride group and conjugated quinoline structure. Its derivatives are employed in developing sensors for metal ions, especially aluminum and zinc, in environmental and biological samples. Also utilized in pharmaceutical research for constructing sulfonamide-based compounds with potential antimicrobial and anti-inflammatory activity. The compound’s ability to form stable conjugates makes it valuable in labeling biomolecules for imaging and diagnostic applications.