Metabolic O-demethylation of 3,4-dimethoxyamphetamine in vivo in dog and monkey.

1. The disposition of the hallucinogen 3,4-dimethoxyamphetamine in vivo was examined in dogs and monkeys. 2. O-Demethylation is important since 3-O-methyl-alpha-methyldopamine (3-methoxy-alpha-methyltyramine) was found in the urine of both species, and traces of alpha-methyldopamine were found in the urine of dogs. 3. Also found in the urine of dogs were 1-(3,4-dihydroxyphenyl)propan-2-one and 3,4-dihydroxybenzoic acid, which are side-chain modified metabolites of alpha-methyldopamine. 4. 1-(3-Methoxy-4-hydroxyphenyl)propan-2-one, a side-chain modified metabolite of 3-O-methyl-alpha-methyldopamine, was present in the urine of both dogs and monkeys. 5. The 3-O-demethylated isomers 4-O-methyldopamine and 1-(3-hydroxy-4-methoxyphenyl)propan-2-one were not detected.