Selective activator of large-conductance Ca2+-activated potassium channels (BKCa, KCa1.1) (EC50 = 11 μM). Activates BK channels in native smooth muscle cells from guinea pig bladder and reduces spontaneous phasic contractions in bladder strips ex vivo. Displays no effect on contractions induced by a high K+ concentration or at 65 other receptors tested, including L- and N- type Ca2+ channels, Nav, KATP and hERG channels. Purity 99%. MW (observed): 269.16