Used as a key intermediate in the synthesis of fluorescent dyes and optical brighteners due to its ability to form rigid, conjugated structures. Its bifunctional carboxylic acid groups allow for easy esterification or amidation, making it valuable in polymer chemistry for modifying resin properties. Also employed in coordination chemistry as a bridging ligand for metal-organic frameworks (MOFs), where its aromatic backbone enhances structural stability. Additionally, it finds use in the preparation of specialty chelating agents for selective metal ion binding in analytical and environmental applications.