Discovery of <i>N</i>-((4-([1,2,4]Triazolo[1,5-<i>a</i>]pyridin-6-yl)-5-(6-methylpyridin-2-yl)-1<i>H</i>-imidazol-2-yl)methyl)-2-fluoroaniline (EW-7197): A Highly Potent, Selective, and Orally Bioavailable Inhibitor of TGF-β Type I Receptor Kinase as Cancer Immunotherapeutic/Antifibrotic Agent
作者:Cheng Hua Jin、Maddeboina Krishnaiah、Domalapally Sreenu、Vura B. Subrahmanyam、Kota S. Rao、Hwa Jeong Lee、So-Jung Park、Hyun-Ju Park、Kiho Lee、Yhun Yhong Sheen、Dae-Kee Kim
DOI:10.1021/jm500115w
日期:2014.5.22
A series of 2-substituted-4-([1,2,4]triazolo[1,5-a]pyridin-6-yl)-5-(6-methylpyriclin-2-yl)imidazoles was synthesized and evaluated to optimize a prototype inhibitor of TGF-beta type I receptor kinase (ALK5), 6. Combination of replacement of a quinoxalin-6-yl moiety of 6 with a [1,2,4]triazolo[1,5-a]pyridin-6-yl moiety, insertion of a methyleneamino linker, and a o-F substituent in the phenyl ring markedly increased ALK5 inhibitory activity, kinase selectivity, and oral bioavailability. The 12b (EW-7197) inhibited ALKS with IC50 value of 0.013 mu M in a kinase assay and with IC50 values of 0.0165 and 0.0121 mu M in HaCaT (3TP-luc) stable cells and 4T1 (3TP-luc) stable cells, respectively, in a luciferase assay. Selectivity profiling of 12b using a panel of 320 protein kinases revealed that it is a highly selective ALKS/ALK4 inhibitor. Pharmacokinetic study with 12b center dot HCl in rats showed an oral bioavailability of 51% with high systemic exposure (AUC) of 1426 ng x h/mL and maximum plasma concentration (C-max) of 1620 ng/mL. Rational optimization of 6 has led to the identification of a highly potent, selective, and orally bioavailable ALK5 inhibitor 12b.