Chemical tools for DYRK1A-mediated diseases.Inhibition of DYRK1A-induced τ phosphorylation at multiple AD-relevant sites (Ser396, Thr212, Thr231).Normalization of Aβ-induced τ phosphorylation in neuronal cells.Normalization of DYRK1A-induced Aβ production in APP overexpressing cells [152,153]. Here, APP is linked to Alzheimer disease.