A potent inhibitor of GSK3α/β (IC₅₀ = 10 nM), with selectivity over Cdk5/p25, Cdk2/A, and Cdk1/B (IC₅₀s = 2.4, 4.3, and 63 µM, respectively); suppresses the cytopathic effects of herpes viruses and reduces viral yields in human oral epithelial cells.