The serotonin (5-HT) receptor affiiities and behavioral (discriminative stimulus) properties of a series of 4-substituted derivatives of 1-(2, 5-dimethoxypheny1)-2-aminopropanes (2, 5- DMA) were investigated. The substituents at the 4-position included H, OMe, OEt, Me, Et, F, Br, I, and NOz. Substituent lipophilicities (T values) of these functionalities appear to have a minimal effect on either 5-HT receptor affinity or behavioral activity. Those derivatives ...