PSB-SB-1202 is a coumarin derivative which is an agonist at the cannabinoid receptors CB<sub>1</sub> and CB<sub>2</sub>, with a CB<sub>1</sub> Ki of 32nM and a CB<sub>2</sub> Ki of 49nM. It is also a weak antagonist at the related receptor GPR55, with an IC<sub>50</sub> of 6350nM, but has no significant affinity for GPR18.