PT - JOURNAL ARTICLE AU - Xi-Ping Huang AU - Tao Che AU - Thomas J Mangano AU - Valerie Le Rouzic AU - Ying-Xian Pan AU - Susruta Majumdar AU - Michael Cameron AU - Michael Bauman AU - Gavril W. Pasternak AU - Bryan L Roth TI - Pharmacology of W-18 and W-15 AID - 10.1101/065623 DP - 2016 Jan 01 TA - bioRxiv PG - 065623 4099 - http://biorxiv.org/content/early/2016/07/24/065623.short 4100 - http://biorxiv.org/content/early/2016/07/24/065623.full AB - W-18 (1-(4-Nitrophenylethyl)piperidylidene-2-(4-chlorophenyl)sulfonamide)and W-15 (4-chloro-N-[1-(2-phenylethyl)-2-piperidinylidene]-benzenesulfonamide) represent two emerging drugs of abuse chemically related to the potent opioid agonist fentanyl (N-(1-(2-phenylethyl)-4-piperidinyl)-N-phenylpropanamide). Here we describe the comprehensive pharmacological profiles of W-18 and W-15. Although W-18 and W-15 have been described as having potent anti-nociceptive activity and are presumed to interact with opioid receptors, we found them to be without detectible opioid activity at μ, δ, κ and nociception opioid receptors in a variety of assays. We also tested W-18 and W-15 for activity as allosteric modulators at opioid receptors and found them devoid of significant positive or negative allosteric modulatory activity. Comprehensive profiling at essentially all the druggable G-protein coupled receptors in the human genome using the PRESTO-Tango platform revealed no significant activity. In silico predictions using the Similarity Ensemble Approach suggested activity for W-18 only weakly at H3-histamine receptors, which was not confirmed in radioligand binding studies. Weak activity at the sigma receptors and the peripheral benzodiazepine receptor were found for W-18 (Ki=271 nM); W-15 displayed weak antagonist activity at 5-HT2-family serotonin receptors. W-18 is extensively metabolized, but its metabolites also lack opioid activity. W-18 and W-15 did inhibit hERG binding suggesting possible cardiovascular side-effects with high doses. Thus although W-18 and W-15 have been suggested to be potent opioid agonists, our results reveal no significant activity at these or other known targets for psychoactive drugs.