SER-601 (COR-167) is a drug which acts as a potent and selective cannabinoid CB<sub>2</sub> receptor agonist, based on a quinolone-3-carboxylic acid core structure, with 190 times selectivity for CB<sub>2</sub> over the related CB<sub>1</sub> receptor. It has analgesic effects in animal studies, as well as neuroprotective effects, but without a "cannabis high" due to its low affinity for CB<sub>1</sub>. A number of related compounds are known, almost all of which have high selectivity for CB<sub>2</sub>.