Cell-permeable. A potent and ATP-competitive inhibitor of PDGF, VEGF and FGF receptor tyrosine kinases (RTKs) with IC₅₀ values of 0.06, 2.43, 3.04 and > 100 μM at PDGFRβ, VEGFR2, FGFR1 and EGFR respectively. Acts as a potent antiangiogenic and antitumor agent.