A selective inhibitor of FGFR4 (IC50s = 3, 591, 493, and 150 nM for FGFR4, 1, 2, and 3, respectively); inhibits proliferation of HCC cells (EC50s = 0.02-0.11 µM) and demonstrates antitumor activity in mice bearing HCC xenografts when administered orally at 100 mg/kg.