Studies on several 7-substituted N,N-dimethyltryptamines.

Several 7-substituted derivatives of N,N-dimethyltryptamine (DMT) were prepared and evaluated in the rat fundus serotonin receptor assay and in a behavioral (discriminative stimulus) assay in rats. Both 7-Me- and 5-OMe-7-Me-DMT possess a higher pA2, and 5,7-(OMe)2-DMT a lower pA2, than that of DMT itself. Like DMT, all three of these compounds produce behavioral effects in rats which are similar to those of the hallucinogen 5-OMe-DMT. Although 7-ET- and 7-Br-DMT possess a higher serotonin receptor affinity than DMT, neither produce behavioral effects which parallel those of 5-OMe-DMT. In contrast, 6-Me-DMT and its 5-OMe derivative do not interact with the serotonin receptors in a competitive manner and are inactive in the discriminative stimulus assay.