A potent inhibitor of PDGF receptor tyrosine kinase (PDGFRalpha and beta), IC50=1 µM (1). Also inhibits FGF receptor tyrosine kinase (2), c-kit (3) and FLT3 (4) and reverses transformation induced by activated FLT3 (5). Induces apoptosis in a small-cell lung cancer cell line (H526) (3). Cell permeable.