Potent and selective acid-sensing ion channel 1a (ASIC1a) blocker (IC50 = 0.9 nM). Displays no effect at ASIC1b, ASIC2a, ASIC3, heteromeric ASIC channels, ENaC and KV2.1/2.2/4.2/4.3 channels expressed in oocytes, at concentrations up to 100 nM. Displays potent analgesic properties against thermal, mechanical, chemical, inflammatory and neuropathic pain in rodents. MW (observed): 4689.41.