AZ191 is a potent and selective DYRK1B inhibitor with IC50 of 17 nM, about 5- and 110-fold selectivity over DYRK1A and DYRK2, respectively.

tBID is a selective inhibitor of homeodomain–interacting protein kinase 2 (HIPK2) with an IC50 of  0.33 µM.

INDY is a potent and ATP-competitive Dyrk1A and Dyrk1B inhibitor with IC50s of 0.24 μM and 0.23 μM, respectively. INDY binds in the ATP pocket of the enzyme and has a Ki value of 0.18 μM for Dyrk1A. INDY sharply reduces the self-renewal capacity of normal and tumorigenic cells in primary Glioblastoma (GBM) cell lines and neural progenitor cells.