5C-D
5C-D, also known as 4-methyl-2,5-dimethoxy-α-propylphenethylamine, is a putatively non-hallucinogenic serotonin 5-HT2 receptor agonist of the phenethylamine and α-propylphenethylamine families related to the 4C drug Ariadne.
At the serotonin 5-HT2A receptor, 5C-D is a potent and higher-efficacy partial agonist, with an of 291nM and an of 69%. It is about half as potent as Ariadne as a serotonin 5-HT2A receptor agonist and has about 15% lower efficacy in activating the receptor in comparison. 5C-D has also been shown to be a serotonin 5-HT2B receptor agonist. In contrast to Ariadne and serotonergic psychedelics, 5C-D does not produce the head-twitch response, a behavioral proxy of psychedelic effects, in rodents.
5C-D was first described in the scientific literature by Michael Cunningham and colleagues by 2023. It was synthesized and assessed during structure–activity relationship studies of Ariadne.