Structural characterization and comparative analysis of polymorphic forms of psilocin (4-hy-droxy-N,N-di-methyl-tryptamine).
Acta crystallographica. Section E, Crystallographic communications May 1, 2024 Matthias Zeller, Stephan Parent, Nate Schultheiss
Psilocin, the primary metabolite of the psychedelic compound psilocybin, crystallizes in two anhydrous polymorphic forms (I and II). Form I, first reported in 1974, was redetermined to modern standards, and its variable-temperature unit-cell parameters were measured. Form II, described for the first time, crystallizes in space group P21/n and exhibits a different molecular conformation: the N,N-dimethylethylene substituent is gauche, allowing the molecule to form a strong intramolecular O–H⋯N hydrogen bond. In Form II, molecules also form one-dimensional strands via N–H⋯O hydrogen bonds, and the structure shows whole-molecule disorder with an occupancy ratio of 0.689:0.311. Form I lacks intramolecular hydrogen bonds and instead forms a layered structure through intermolecular N–H⋯O and O–H⋯N hydrogen bonds.