Identification of anhydroecgonine methyl ester N-oxide, a new metabolite of anhydroecgonine methyl ester, using electrospray mass spectrometry.
Cocaine is transformed into hepatotoxic metabolites through oxidative pathways. For anhydroecgonine methyl ester (AEME), the main constituent in crack smoke, the oxidative metabolism has not been studied. Therefore, incubation of AEME with rat liver microsomes was performed and a metabolite of AEME, anhydroecgonine methyl ester N-oxide (AEMENO), was identified. The chemical structure of this new metabolite was confirmed by synthesis and by comparative interpretation of electrospray multiple-stage mass spectra, which were obtained in the positive ion mode. This metabolite was also detected in whole blood, serum and urine samples from crack users. The application of liquid chromatography/electrospray mass spectrometry or nanoelectrospray mass spectrometry was necessary because AEMENO is susceptible to thermal degradation during gas chromatographic/mass spectrometric analysis. This study demonstrated that AEMENO is produced by rat hepatic microsomal metabolism in vitro and is present in body fluids from crack users.
Institute of Forensic Toxicology, J. W. Goethe University, Kennedyallee 104, 60596 Frankfurt/Main, Germany.
Anabel S
AS
Fandiño
Michael
M
Karas
Stefan W
SW
Toennes
Gerold
G
Kauert
D000818:Animals; D001711:Biotransformation; D002851:Chromatography, High Pressure Liquid; D003042:Cocaine / Q000031:analogs & derivatives* / Q000032:analysis* / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D016578:Crack Cocaine / Q000493:pharmacokinetics / Q000506:poisoning; D003932:Heroin / Q000506:poisoning; D006801:Humans; D008862:Microsomes, Liver / Q000378:metabolism; D015394:Molecular Structure; D010084:Oxidation-Reduction; D051381:Rats; D012907:Smoking; D021241:Spectrometry, Mass, Electrospray Ionization
D016578:Crack Cocaine; C463339:anhydroecgonine methyl ester N-oxide; C068464:anhydroecgonine methyl ester; D003932:Heroin; D003042:Cocaine