4-AcO-MiPT, or 4-acetoxy-N-methyl-N-isopropyltryptamine, is a synthetic tryptamine with an acetoxy group at the 4-position of the indole ring. It is structurally related to 4-HO-MiPT and belongs to the same broad group as psilacetin and other 4-acetoxy tryptamines. Laboratory receptor assays have characterised its activity, but direct human metabolism and clinical data remain limited.
Chemistry and relationship to 4-HO-MiPT
4-AcO-MiPT has an indole core with a 4-acetoxy substituent and a methyl-isopropyl group on the terminal nitrogen. It differs from 4-AcO-MET by the replacement of the ethyl group with an isopropyl group. The corresponding hydroxy compound is 4-HO-MiPT, also known as miprocin.
The compound has been included in analytical reference collections and in studies of substituted tryptamine pharmacology. Its chemical identity should be distinguished from 4-AcO-DiPT, which has two isopropyl groups on the terminal nitrogen.
Receptor pharmacology
A 2023 study measured the activity of 4-AcO-MiPT at human 5-HT1A, 5-HT2A and 5-HT2C receptors, as well as the serotonin transporter. In the 5-HT2A functional assay, it showed agonist activity with an EC50 of approximately 445 nM and efficacy of about 69% relative to serotonin. Its activity differed across receptor subtypes, and it showed lower potency than some of the other 4-substituted tryptamines in the study (Kozell and colleagues, 2023).
Metabolism and possible deacetylation
Because 4-AcO-MiPT is the acetate ester of 4-HO-MiPT, hydrolysis is a plausible metabolic route. Research on other acetoxy tryptamines supports this possibility, but direct human hepatocyte or clinical pharmacokinetic data specific to 4-AcO-MiPT are not well established.
The 2023 receptor study found measurable activity for the intact compound. It therefore cannot be described solely as an inactive precursor without further evidence.
Reported effects and research limitations
Human descriptions are largely anecdotal, and there are no controlled clinical studies that establish a characteristic subjective profile, duration or adverse-event frequency. Comparisons with 4-HO-MiPT may be useful for describing the structural relationship, but they do not prove that the two compounds have identical effects.
Its acute toxic range, dependence liability and long-term effects remain uncertain. Activity in a receptor assay does not establish safety in humans.
Related tryptamines
4-AcO-MiPT is related to 4-HO-MiPT, 4-AcO-MET, 4-AcO-DMT and 4-AcO-DiPT. Its methyl-isopropyl substitution on the terminal nitrogen distinguishes it from the other compounds in this group.
