O-4310, also known as 1-isopropyl-6-fluoropsilocin, is a serotonin receptor agonist of the tryptamine family.

[2] Its EC50Tooltip half-maximal effective concentration at the serotonin 5-HT2A receptor was reported to be 5 nM and it was said to have an EmaxTooltip maximal efficacy of 89% relative to serotonin.

[2] The pharmacodynamic activity of O-4310 was briefly described in a patent but not in the published scientific literature.

[3] O-4310 was patented by Bryan Roth and colleagues in 2006 and the patent was assigned to the American pharmaceutical company Organix Inc as well as a couple of other assignees.

[2] The drug was also employed in an animal study and described in the scientific literature by a group of Iranian researchers in 2017.