Biosynthesis of Psilocybin. Part II. Incorporation of Labelled Tryptamine Derivatives.

Abstract

Psilocybin (VI) and psilocin (V) are two hallucinogenic compounds present in a number of mushrooms mainly members of the genus Psilocybe (cf.1).-The compounds are closely related 4-hydroxylated indoles and it has been shown by Brack et al. (2) and us (1) that psilocybin may biosynthetically derive from tryptophan and tryptamine. The tryptophan molecule (I) requires the following modifications in a definite or alternative order for conversion to psilocybin: decarboxylation, methylation, hydroxylation and phosphoryla-tion. We have now obtained experimental results consistent with the sequence of biosynthesis for psilocybin in Psilocybe cubensis shown in the scheme below. However, this is apparently not the only pathway to psilocybin which the fungus may utilize.