The Chemistry of 4-HO-MiPT
4-HO-MiPT is the N-methyl-N-isopropyl analog of psilocin (aka 4-HO-DMT, 4-hydroxy-N,N-dimethyltryptamine).1 In 1981, Repke et al. reported the synthesis of 4-HO-MiPT.2
In 2019, researchers solved the crystal structure of the fumarate salt of 4-HO-MiPT.3 They describe it as,
a protonated tryptammonium cation and a 3-carboxyacrylate (hydrogen fumarate) anion in the asymmetric unit, [and] contains a water molecule of crystallization.
In 2020, the same team of researchers solved another crystal structure of 4-HO-MiPT.4 They reacted the salt from their previous study with lead(II) acetate. This formed the 4-hydroxy-N-methyl-N-isopropyltryptamine/fumarate compound in a 2:1 ratio, namely bis(4-hydroxy-N-isopropyl-N-methyltryptammonium) fumarate. The authors describe the structure as,
…a singly protonated tryptammonium cation and one half of a fumarate dianion in the asymmetric unit.
The Pharmacology of 4-HO-MiPT
A 1985 study done by Repke, Grotjahn, and Shulgin examined the psychomimetic effects of adding various oxygen substituents to MiPT (N-methyl-N-isopropyltryptamine).5 They reported that the 4-HO-MiPT variation was “…the most interesting in terms of overall effect,” being the only analog to have effects similar to the classic hallucinogens. In 1990, McKenna, Repke, and Peroutka reported that 4-HO-MiPT was less potent at the serotonin 5-HT1A, 5-HT2A, and 5-HT2B receptors than psilocin.6
In TiHKAL (see entry #22), Alexander and Ann Shulgin proposed that “With the 4-hydroxyl group assuring some measure of oral activity, all of these [psilocin homologs] could serve as a structural activity relationship gestalt to selectively, and specifically, evaluate the geometric nature of the nitrogen substituents.” 1
The Applications and Potential of 4-HO-MiPT
There is virtually nothing known about the pharmacology of 4-HO-MiPT. Solving the crystal structures of the fumarate salt of 4-HO-MiPT presents a new chemistry of this compound for further research to understand its therapeutic potential.