The hallucinogenic mushroom Psilocybe semilanceata contains psilocybin and baeocystin at varying levels, with psilocybin ranging from 0.21 to 2.02% and baeocystin from 0.05 to 0.77%, while psilocin appears only in trace amounts. Analysis of 52 samples collected across multiple sites in Switzerland over one to five years showed that alkaloid content varies with the mushroom's origin, year of collection, size, and the part of the mushroom tested. These findings describe the chemical variability of tryptamine derivatives in this species.
Baeocystin, a naturally occurring psilocybin-related alkaloid, was synthesized from 2-methyl-3-nitrophenol. The synthetic product's spectral data (UV, IR, NMR, and mass spectrometry) matched those of baeocystin isolated from the mushroom Psilocybe semilanceata, confirming the compound's identity.