CID 16020046 is a potent and selective GPR55(LPI receptor) antagonist; inhibitsGPR55 constitutive activity with IC50 of 0.15 uM.

(R,S′)-MNF is a bi-functional GPR55 inhibitor and biased β2 adrenergic agonist, inhibits proliferation of PDAC cell lines (IC50=0.11 uM, PANC-1 cells). (R,S′)-MNF is a biased β2-AR agonist that selectively signals through Gαs and does not recruit β-arrestin-2. (R,S′)-MNF attenuates pro-oncogenic signaling and cellular proliferation in PANC-1 cells. (R,S′)-MNF (1 uM) significantly decreased ERK phosphorylation stimulated by the GPR55 ligand O-1602, (R,S′)-MNF is an effective inhibitor of GPR55 internalization and signaling. (R,S′)-MNF (20-40 mg/Kg) reduces PANC-1 tumor growth in a mouse xenograft model.

Tocrifluor 1117 (T1117), a fluorescent form of the cannabinoid CB1 receptor antagonist AM251, is a selective fluorescent GPR55 ligand. Tocrifluor 1117 is a potent tool for identifying the cellular location of cannabinoid receptors (including GPR55 in living tissues) (Ex/Em=543/590 nm).

CID1792197 is a potent, selective GPR55 agonist with EC50 of 110 nM in the β-arrestin trafficking assay,100-fold selectivity for GPR55 over GPR35, CB1 and CB2.