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A 83-01
Activators & Inhibitors
Chemical Modulators

A 83-01 #75073

Citations (0)
Western blot analysis of extracts from HT-1080 cells, untreated (-) or treated with Human Transforming Growth Factor β1 (hTGF-β1) #8915 (10 ng/ml, 30 min; +) with or without pretreating the cells with A 83-01 (1 μM, 1 hr; +), using Phospho-Smad2 (Ser465/467)/Smad3 (Ser423/425) (D27F4) Rabbit mAb #8828 (upper), Smad2/3 (D7G7) XP® Rabbit mAb #8685 (middle), or β-Actin (D6A8) Rabbit mAb #8457 (lower).
Chemical structure of A 83-01.

Product Usage Information

A 83-01 is supplied as a lyophilized powder. For a 10 mM stock, reconstitute 5 mg of powder in 1.18 ml of DMSO. Working concentrations and length of treatment can vary depending on the desired effect.


Store lyophilized at -20ºC, desiccated. In lyophilized form, the chemical is stable for 24 months. Once in solution, store at -20ºC and use within 2 months to prevent loss of potency. Aliquot to avoid multiple freeze/thaw cycles.

Product Description

Molecular Weight 421.5 g/mol
Purity >98%
Molecular Formula C25H19N5S
CAS 909910-43-6
Solubility Soluble in DMSO at 20 mg/ml.


A 83-01 is a potent and selective inhibitor of TGF-β type I receptor ALK5 kinase, activin type IB receptor ALK4, and nodal type I receptor ALK7 with an IC50 value of 12, 45, and 7.5 nM, respectively (1). This small molecule has also been shown to inhibit Smad2/3 phosphorylation along with TGF-β-induced growth inhibition and induction of Twist and Wnt3 (1,2). A 83-01 can be used to stabilize rat induced pluripotent stem cell (riPSC) cultures by inhibiting spontaneous differentiation and increasing the clonal expansion efficiency (3).

Limited Uses

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For Research Use Only. Not for Use in Diagnostic Procedures.
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To Purchase # 75073
Cat. # Size Qty. Price
5 mg