4-HO-MET, or 4-hydroxy-N-ethyl-N-methyltryptamine, is a synthetic indole alkaloid molecule of the tryptamine chemical class. Tryptamines share a core structure comprised of a bicyclic indole heterocycle. Hence, its attached at R3 to an amino group via an ethyl side chain.
4-HO-MET substitutes at R4 of its indole heterocycle with a hydroxyl functional group OH−. It also contains a methyl group and an ethyl chain. This is bound to the terminal amine RN of its tryptamine backbone (MET).