(R)-69
-69 is a drug of the tetrahydropyridinylpyrrolopyridine family related to the psychedelic tryptamines which acts as a 5-HT2A receptor agonist, with 4.6-fold selectivity over 5-HT2B and 49-fold selectivity over 5-HT2C. It has a 5-HT2A Ki of 680 nM and an EC50 of 41 nM. -69 is a biased agonist selective for activation of the Gq coupled signalling pathway, with much weaker activation of the β-arrestin 2 coupled pathway. In animal studies it produces antidepressant-like activity but without producing the head-twitch response associated with psychedelic effects. The drug was identified along with its close analogue (R)-70 via an ultra-large-scale docking campaign against the serotonin 5-HT2A receptor and was first described by Bryan L. Roth and colleagues in 2022. A number of related derivatives have also been developed.