TBK1/IKKε-IN-4, a 6-aminopyrazolopyrimidine derivative, serves as a potent, selective inhibitor for TBK1 and IKKε, demonstrating IC50 values of 13 nM and 59 nM, respectively. This compound exhibits significantly reduced activity, by 100- to 1000-fold, against other protein kinases, such as PDK1, PI3K family members, and mTOR[1].

TBK1:13 nM (IC50), IKKε:59 nM (IC50)

TBK1/IKKε-IN-4 (Compound II; 96 hours; A549 andHCC44 cells) treatmentdisplays selective toxicity in TBK1-dependent cancer cell lines (IC50 of ~ 4.2 μM for H441 cells and IC50 of ~0.4 μM for A549 cells)[1].TBK1/IKKε-IN-4 (Compound II; 0-2 μM; 30 minutes; HCC44 cells) treatment inhibits the AKT activity[1].TBK1/IKKε-IN-4 (Compound II) inhibits LPS-induced expression of IFNβ (IC50 =62 nM), and the IFNβ target genes IP10 (IC50 =78 nM) and Mx1 (IC50=20 nM). TBK1/IKKε-IN-4 effectively blocksTLR3-dependent IRF3 nuclear translocation in cells with an IC50 under 100 nM, but does not impair TNFR1-dependent p65 NFκB nuclear translocation with doses as high as 20 μM[1].