Inhibitor Expert (Inhibitors, Compound Libraries)



Technical Data

Molecular Weight 352.75 Storage powder


in solvent
CAS No. 627536-09-8 Synonyms N/A
Chemical Name 2-(5-chloro-2-fluorophenyl)-N-(pyridin-4-yl)pteridin-4-amine
Solubility (25°C) * In vitro DMSO 9 mg/mL warmed (25.51 mM)
Water Insoluble
Ethanol Insoluble
In vivo 1% methylcellulose 8mg/mL
* <1 mg/ml means slightly soluble or insoluble.
* Please note that Selleck tests the solubility of all compounds in-house, and the actual solubility may differ slightly from published values. This is normal and is due to slight batch-to-batch variations.

Biological Activity

Description SD-208 is a selective TGF-βRI (ALK5) inhibitor with IC50 of 48 nM, >100-fold selectivity over TGF-βRII.
TGF-βRI (ALK5) [1]
(Cell-free assay)
48 nM
In vitro SD-208 inhibits the cell growth and constitutive and TGF-beta-evoked migration and invasion, and enhances immunogenicity in murine SMA-560 and human LN-308 glioma cells. [1] SD-208 blocka TGF-beta-induced phosphorylation of the receptor-associated Smads, Smad2 and Smad3, and stimulates epithelial-to-mesenchymal transdifferentiation, migration, and invasiveness into Matrigel in vitro. [2] SD-208 also abolishes the promoting effect of TGF-β on neointimal smooth muscle-like cell (SMLC) proliferation and migration in vitro. [3]
In vivo SD-208 (1 mg/mL, p.o.) significantly prolongs the median survival of SMA-560 glioma-bearing mice. [1] In syngeneic 129S1 mice, SD-208 (60 mg/kg/d, p.o.) inhibits primary R3T tumor growth, and reduces the number and the size of lung metastases. [2] In the murine aortic allograft model, SD-208 effectively reduces the formation of intimal hyperplasia of transplant arteriosclerosis (TA). [3]

Protocol (Only for Reference)

Kinase Assay: [1]
Kinase assay Various kinase activities are assayed by measuring the incorporation of radiolabeled ATP into a peptide or protein substrate. The reactions are performed in 96-well plates and included the relevant kinase, substrate, ATP, and appropriate cofactors. The reactions are incubated and then stopped by the addition of phosphoric acid. Substrate is captured onto a phosphocellulose filter, which is washed free of unreacted ATP. The counts incorporated are determined by counting on a microplate scintillation counter. The ability of SD-208 to inhibit the respective kinase is determined by comparing counts incorporated in the presence of compound with those incorporated in the absence of compound.
Cell Assay: [1]
Cell lines Murine SMA-560 and human LN-308 glioma cells
Concentrations 1 μM
Incubation Time 48 hours
Method Glioma cells are cultured in the absence or presence of SD-208 (1 μM) for 48 hours. The cells are pulsed for the last 24 hours with [methyl-3H]thymidine (0.5 μCi) and harvested, and incorporated radioactivity is determined in a liquid scintillation counter.
Animal Study: [1]
Animal Models VM/Dk mice bearing SMA-560 tumors
Formulation deionized water
Dosages 1 mg/mL
Administration p.o.




Specific storage and handling information for each product is indicated on the product datasheet. Most Selleck products are stable under the recommended conditions. Products are sometimes shipped at a temperature that differs from the recommended storage temperature. Short-term storage of many products are stable in the short-term at temperatures that differ from that required for long-term storage.
We ensure that the product is shipped under conditions that will maintain the quality of the reagents. Upon receipt of the product, follow the storage recommendations on the product data sheet.

Chemical Structure

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