DYRK1A and head and neck squamous cell carcinoma: Based on the JH-XIV-68-3 inhibitor (compound 3) that displays selectivity for Dyrk1A/Dyrk1B in biochemical and cellular assays, as well as an antitumor efficacy in head and neck squamous cell carcinoma (HNSCC) cell lines, the derivative JH-XVII-10 inhibitor (compound 10) was generated by the introduction of fluorine to block the 2-position of the azaindole, rendering the molecule resistant to aldehyde oxidase (AO) activity, in which the JH-XIV-68-3 inhibitor (compound 3) is vulnerable (Figure 3).