FIIN-3 is a potent, irreversible inhibitor of fibroblast growth factor receptor (FGFR) kinases (FGFR1, FGFR2, and FGFR3), primarily utilized in biochemical research to study and inhibit these specific enzymes involved in cancer pathways. It is often employed in laboratory settings to investigate the mechanisms of FGFR signaling and to evaluate its potential as a therapeutic agent in targeting FGFR-driven diseases. Researchers use FIIN-3 to explore its effects on cell proliferation, survival, and apoptosis, providing insights into its efficacy in disrupting cancer cell growth. Additionally, it serves as a valuable tool in drug discovery efforts, helping to identify and optimize FGFR inhibitors for clinical applications.