LY364947 is a selective inhibitor of TGF-β RI (TGFR-I, TβR-I, ALK-5), with an IC50 value of 59 nM. LY364947 only weakly inhibits TGF-β RII (IC50 = 400 nM), p38 MAPK (IC50 = 740 nM), and mixed lineage kinase-7 (MLK-7; IC50 = 1,400 nM).It inhibits TGF-β-induced cell growth (IC50 = 89 nM) in NIH 3T3 mouse fibroblasts and TGF-β-directed Smad phosphorylation, synthesis of fibronectin, PAI-1 and uPA protein, and matrigel invasion in MDA-MB-231 cells. MW: 272.31. Purity ≥98% by HPLC