Abstract
Tryptamines are widely distributed in nature and include biologically important molecules such as serotonin, together with naturally occurring N,N-dialkylated compounds including DMT, 5MeO-DMT, and bufotenine. Halogenated tryptamines, such as 5-bromo-DMT and 5-chloroDMT, have also been identified in marine organisms, illustrating how relatively small structural modifications contribute to the remarkable chemical diversity of this family. More recently, the clinical development of bretisilocin (GM-2505; 5-fluoro-N-methyl-N-ethyltryptamine) to treat major depressive disorder has renewed interest in understanding how structural modification of the halogenated tryptamine scaffold influences biological activity. These developments highlight the importance of understanding how halogen substitution and N-alkyl group steric bulk influence the chemical behavior and structural properties of tryptamine derivatives. To investigate these effects, series of halogen-substituted N-isopropyltryptamine (NIPT), N,Ndiisopropyltryptamine (DiPT), and N,N,N-tributyltryptammonium iodide (TBTI) derivatives were synthesized and characterized using multinuclear NMR spectroscopy and single-crystal Xray diffraction. This work expands the structural chemistry of halogenated tryptamine derivatives and provides a foundation for future biological and structure–activity relationship investigation.