Potent and selective blocker of KCNQ voltage-gated potassium channels. Blocks KCNQ2+3/M-currents (IC50 = 0.6 - 0.98 μM) and KCNQ1 homomeric channels (IC50 = 0.75 μM) but is less potent against KCNQ1/minK channels (IC50 = 11.1 μM). Augments hippocampal ACh release and is a cognitive enhancer following oral administration in vivo.