Revisiting 1,3,4-Oxadiazol-2-ones: Utilization in the Development of ABHD6 Inhibitors

This article describes our systematic approach to exploring the utility of the 1,3,4-oxadiazol-2-one scaffold in the development of ABHD6 inhibitors. Compound 3-(3-aminobenzyl)-5-methoxy-1,3,4-oxadiazol-2(3H)-one (JZP-169, 52) was identified as a potent inhibitor of hABHD6, with an IC50 value of 216nM. This compound at 10μM concentration did not inhibit any other endocannabinoid hydrolases, such as FAAH, MAGL and ABHD12, or bind to the cannabinoid receptors (CB1 and CB2). Moreover, in competitive activity-based protein profiling (ABPP), compound 52 (JZP-169) at 10μM selectively targeted ABHD6 of the serine hydrolases of mouse brain membrane proteome. Reversibility studies indicated that compound 52 inhibited hABHD6 in an irreversible manner. Finally, homology modelling and molecular docking studies were used to gain insights into the binding of compound 52 to the active site of hABHD6.