SB-431542 (301836-41-9) is a potent and selective ALK4, ALK5 and ALK7 inhibitor (TGFβ superfamily Type I activin receptor-like kinase). (ALK5 IC₅₀ = 94 nM)^1,2. Inhibits TGFβ-induced proliferation of human osteosarcoma cells³. Ehances growth and integrity of embryonic stem cell-derived endothelial cells⁴. SB-431542 is a frequently used agent employed in numerous stem cell differentiation protocols⁵. Cell permeable.

References/Citations
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2) Inman et al. (2002), SB-431542 is a potent and specific inhibitor of transforming growth factor-beta superfamily type I activin receptor-like kinase (ALK) receptors ALK4, ALK5 and ALK7; Mol. Pharmacol., 62 65
3) Matsuyama et al. (2003), SB-431542 and Gleevec inhibit transforming growth factor-beta-induced proliferation of human osteosarcoma cells; Cancer Res., 63 7791
4) Watabe et al. (2003), TGF-beta receptor kinase inhibitor enhances growth and integrity of embryonic stem cell-derived endothelial cells; J. Cell Biol., 163 1303
5) Stanslowsky et al. (2014), Functional differentiation of midbrain neurons from human cord blood-derived induced pluripotent stem cells; Stem Cell Res. Ther., 5 35