Selective inhibitor of EGF receptor tyrosine kinase (IC50 values are 2 and 13.5 μM for EGFR and ErbB2 respectively). Inhibitor of JAK2, JAK3/STAT, JAK3/AP-1 and JAK3/MAPK pathways and potently inhibits cytokine-independent cell growth in vitro and tumor cell invasion in vivo.