The Synthesis and Pharmacological Evaluation of Adamantane-Derived Indoles: Cannabimimetic Drugs of Abuse

Two novel adamantane derivatives, adamantan-1-yl(1-pentyl-1H-indol-3-yl)methanone (AB-001) and N-(adamtan-1-yl)-1-pentyl-1H-indole-3-carboxamide (SDB-001), were recently identified as cannabimimetic indoles of abuse. Conflicting anecdotal reports of the psychoactivity of AB-001 in humans, and a complete dearth of information about the bioactivity of SDB-001, prompted the preparation of AB-001, SDB-001, and several analogues intended to explore preliminary structure–activity relationships within this class. This study sought to elucidate which structural features of AB-001, SDB-001, and their analogues govern the cannabimimetic potency of these chemotypes in vitro and in vivo. All compounds showed similar full agonist profiles at CB1 (EC50 = 16–43 nM) and CB2 (EC50 = 29–216 nM) receptors in vitro using a FLIPR membrane potential assay, with the exception of SDB-002, which demonstrated partial agonist activity at CB2 receptors. The activity of AB-001, AB-002, and SDB-001 in rats was compared to that of Δ9-t...