Dual inhibitor of receptor tyrosine kinases (RTKs) (IC50 < 0.02 μM for Abl, Src, VEGFR-2 and PDGFR) and PI 3-K family kinases (IC50 < 0.06 μM for p110α, DNA-PK and mTOR). Exhibits no significant effect on receptor serine/threonine kinases (RSTKs). Blocks the proliferation of tumor cells by direct inhibition of PI 3-K, mTOR, Src and the VEGF receptor.