FGFR-IN-4 is a potent inhibitor of FGFR. Fibroblast growth factor receptor ( FGFR ) is a tyrosine kinase receptor that binds to fibroblast growth factor ligands. FGFR-IN-4 has the potential for the research of cancer diseases (extracted from patent WO2022033532A1, compound 20). FGFR-IN-4 is a click chemistry reagent, it contains an Alkyne group and can undergo copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups.