FLT3-IN-1 is a potent and selective inhibitor of FMS-like tyrosine kinase 3 (FLT3), particularly effective against the FLT3-ITD mutant form commonly found in acute myeloid leukemia (AML). It is primarily used in research settings to study FLT3 signaling pathways and evaluate therapeutic strategies for AML. By inhibiting FLT3 autophosphorylation and downstream signaling, FLT3-IN-1 induces cell cycle arrest and promotes apoptosis in FLT3-dependent leukemia cell lines. Its high selectivity makes it a valuable tool compound for validating FLT3 as a drug target and for assessing the efficacy of targeted inhibition in preclinical models of leukemia. It is not intended for clinical use but supports the development of more advanced FLT3-targeted therapies.