AAL-993 is a potent, selective and cell-permeable inhibitor of VEGFR-1 (IC₅₀ = 130 nM), VEGFR-2 (IC₅₀ = 23 nM) and VEGFR-3 (IC₅₀ = 18nM). At higher concentrations it inhibits PDGFR (640 nM), c-Kit (236 nM) and CSF-1R (380 nM). Inactive at other kinases such as EGFR, FGFR-1, CDK-1, Tie-2, c-Met, IGF-1R, c-Src and c-Abl. X-ray crystal studies on AAL-993 complexed to the catalytic domain of diphosphorylated VEGFR- 2 indicates that it binds to an inactive conformation of the protein. AAL-993 inhibits VEGF-induced angiogenesis (mouse model).