A New Group of Psychotomimetic Agents.

Abstract

Recently, a group of piperidyl benzilates possessing anticholinergic properties and structurally related to atropine were found to be very powerful psychotogens. Among the psychotogenic effects in human volunteers were auditory and visual hallucinations, gross distortions of visual images, delusions, disorientation, confusion, and severe alterations in affective states. Almost invariably the experience was an extremely unpleasant one, largely due to a fear of losing contact with the immediate environment. A series of congeners have been synthesized and the structural relationships have been examined from the point of view of psychotogenic effect. Among the more powerful psychotogens is N-methyl-3-piperidyl benzilate. A quaternary nitrogen in the piperidine ring abolishes activity, by preventing entry into the brain, while substitution of H for OH in the benzilic acid moiety completely abolishes psychotogenic activity. There appears to be little relationship between anticholinergic and psychotogenic potency.