Bruton’s tyrosine kinase (Btk) inhibitorstirabrutinib (35) and acalabrutinib (36)87 (used to treat inter alia chronic lymphocyticleukemiaand lymphoma, respectively) contain an yneamide group, the electrophilicalkyne of which covalently reacts with the nucleophilic thiolate ofBtk Cys481 resulting in efficient inhibition (Figure 6b),87,88 further highlightingthe use of alkynes as clinically useful warheads. The gene discussed is BTK; the disease is lymphoma.