A cell-permeable benzotriazolo compound that acts as a higly selective, reversible, and ATP/GTP-competitive inhibitor of casein kinase-2 (CK2) (IC
50 = 900 nM and 1.6 µM, using rat liver and human recombinant CK2, respectively) and DYRK (IC
50 < 1 µM for DYRK1a). Its specificity has been demonstrated using a panel of 33 kinases, including PKA, PKB, PKC, MKK1, Erk2, p38, JNK, Lck, Lyn, and Syk. Also shown to inhibit NS3-associated viral helicase activities in HCV (IC
50 = 20 and 60 µM, using DNA and RNA substrate, respectively) and WNV (IC
50 = 1.7 and 900 nM, using DNA and RNA substrate, respectively). A 10 mM (5 mg/1.15 ml) solution of Casein Kinase II Inhibitor I (Cat. No.
218708) in DMSO, is also available.