Fungal metabolism of 4-substituted amphetamines.

1. rac.-4-Ethoxyamphetamine was incubated with 14 different yeast and fungal microorganisms. 4-Hydroxyamphetamine was the major metabolite; traces of N-acetyl-4-ethoxyamphetamine were also detected. 2. The major fungal (Cunninghamella) metabolite of 4-propoxyamphetamine and 4-benzyloxyamphetamine was 4-hydroxyamphetamine. The major metabolites of 4-methoxyamphetamine were N-acetyl-4-methoxyamphetamine and 4-hydroxyamphetamine. 3. Acetoin derivatives were formed when alkoxyamphetamine substrates were incubated in the presence of various fungi and yeasts. 4. The findings indicate that Cunninghamella echinulata may be a useful microbial model for drug disposition and interaction studies.