An antagonist of GPR55, blocking LPI-induced activation (EC50 = 1.1 μM); has minimal effect at the GPR35 and CB2, although it acts as a weak antagonist of CB1 (IC50 = 17.7 μM); inhibits LPI-induced phosphorylation of ERK1/2 and blocks receptor-dependent translocation of PKCβII (IC50 = 0.33 nM)