AG-370 is a protein tyrosine kinase (PTK) inhibitor that shows potential antiproliferative agents for diseases effected by the hyperactivity of PTKs. Tyrphostins are a class of antiproliferative compounds, selectively inhibiting PTKs of key growth factors like epidermal growth factor (EGF) or platelet-derived growth factor (PDGF) through blocking of the phosphorylation of specific tyrosine residues. AG-370 is a selective inhibitor of PDGFR kinase. It displays comparatively weak inhibition of the EGF receptor.