It is determined that Zegocractin (compound 1) inhibits Orai 1/STIM1 channels with an IC50 of 119 nM, and Orai2/STIM1 channels with an IC50 of 895 nM. It is more potent on Orai1 than Orai2-type CRAC channels. In human PBMCs, Zegocractin potently inhibits release of multiple cytokines which play important roles in T cells (IC50s, IFN γ: 138 nM, IL-4: 879 nM, IL-6: 135 nM, IL-1β: 240 nM, IL-10: 303 nM, TNFα: 225 nM, IL-2: 59 nM, IL-17 120 nM).