Kv2.1 and Kv2.2 channel blocker (IC50 values are 1-3 nM). Enhances glucose-stimulated insulin secretion from human islets in vitro, but not from islet cells lacking the Kv2.1 channel. Has no significant effect on plasma insulin, glucagon or blood glucose levels in mice, but increases plasma somatostatin levels. MW (observed): 3948.61.