Sigma-1 receptor antagonist 3 is a more potent and selective antagonist of Sigma-1 (σ1) receptor (Ki = 1.14 nM) than σ2 receptor(Ki = 1239 nM). Sigma-1 receptor antagonist 3 inhibits Human Ether-a-go-go-Related Gene (hERG, IC50 = 1.54 μM)