TASK-1-IN-1 is a potent and selective TASK-1 (Potassium Channel) inhibitor with an IC50 of 148 nM. TASK-1-IN-1 shows a reduced inhibition of TASK-3 channels (IC50 of 1750 nM) and not a significant effect on other K+ channels. TASK-1-IN-1 has anticancer effects.