Used in the synthesis of fluorescent dyes and optical brighteners due to its conjugated structure and strong light absorption properties. Commonly employed in imaging applications, including biological staining and sensor development, where fluorescence detection is required. Also serves as a building block in the preparation of pharmaceutical intermediates and functional materials for optoelectronic devices. Its carboxylic acid group allows for easy conjugation with other molecules, making it valuable in bioconjugation techniques and probe design.