RG 14921 

RG 14921, a compound structurally related to erbstatin, was investigated for its mechanism of inhibition of epidermal growth factor (EGF) receptor tyrosine kinase and CAMP-dependent kinase activity by kinetic analysis. Both compounds are slow-binding inhibitors of EGF receptor kinase. Erbstatin inhibits EGF receptor kinase as a partially competitive inhibitor relative to ATP and peptide substrates, suggesting that it binds at different positions in the enzyme's ATP- and peptide substrate-binding sites, thereby reducing the enzyme's binding affinity for both substrates. In contrast, the derivative RG 14921 inhibits EGF receptor kinase activity as a noncompetitive inhibitor relative to ATP and peptide substrates. Structurally related compounds exhibit different modes of inhibition, suggesting that the catalytic center of the receptor kinase domain may have a dynamic and possibly extended structure. Erbstatin and RG 14921 exerted similar effects on CAMP-dependent protein kinase activity. In this system, both compounds exhibited strong inhibition and acted in a competitive inhibition manner with ATP and a noncompetitive inhibition manner with peptide substrates.

203.19

C₁₁H₉NO₃

144909-21-7

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. INHIBITION KINETICS AND SELECTIVITY OF THE TYROSINE KINASE INHIBITOR ERBSTATIN AND A PYRIDONE-BASED ANALOGUE