Used primarily as a selective colorimetric and fluorogenic chemosensor for detecting thiol-containing compounds, especially cysteine and homocysteine in biological systems. The compound undergoes a nucleophilic aromatic substitution reaction with thiols, resulting in a distinct color change from colorless or pale yellow to deep red or purple, enabling naked-eye detection. This property makes it valuable in biochemical assays and diagnostic tools for monitoring cellular thiol levels. It is also employed in environmental and pharmaceutical analysis due to its high selectivity and sensitivity in aqueous and semi-aqueous media. Additionally, it serves as a building block in the development of smart probes for imaging reactive sulfur species in live cells.