Methadone chemical structure

Metabolic N-demethylation of methadone occurs since incubation of levo methadone with rat liver slices results in the formation of formaldehyde at a rate only marginally less than that obtained with pethidine as substrate. °2) The reason for the failure of early attempts to isolate the corresponding secondary amine is now well established as due to the facile cyclization of N-desmethylmethadone to a pyrroline derivative. Chemical studies have confirmed the cyclic structure 3 (13) the corresponding free base is an exocyclic alkene 2 that exists as an approximately 50 50 mixture of c-t isomers.(14)... 

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