First synthesized by Albert Hofmann in 1963, 4-AcO-copyright, or O-Acetylpsilocin, is a semi-synthetic derivative of psilocin. It is structurally similar to the naturally occurring alkaloid found in psilocybin mushrooms, differing only by the presence of an acetoxy group. Due to its 4 aco copyright fumarate close relationship with other tryptamines