Piperazine-derived designer drug 1-(3-chlorophenyl)piperazine (mCPP): GC-MS studies on its metabolism and its toxicological detection in rat urine including analytical differentiation from its precursor drugs trazodone and nefazodone.

Abstract

Studies on the metabolism and the toxicological analysis of the piperazine-derived designer drug 1-(3-chlorophenyl)piperazine (mCPP) in rat urine using gas chromatography-mass spectrometry (GC-MS) are described. mCPP was extensively metabolized, mainly by hydroxylation of the aromatic ring and by degradation of the piperazine moiety to the following metabolites: two hydroxy-mCPP isomers, N-(3-chlorophenyl)ethylenediamine, 3-chloroaniline, and two hydroxy-3-chloroaniline isomers. The hydroxy-mCPP metabolites were partially excreted as the corresponding glucuronides and/or sulfates, and the aniline derivatives were partially acetylated to N-acetyl-hydroxy-3-chloroaniline isomers and N-acetyl-3-chloroaniline. Our systematic toxicological analysis (STA) procedure using full-scan GC-MS after acid hydrolysis, liquid-liquid extraction, and microwave-assisted acetylation allowed the detection of mCPP and its previously mentioned metabolites in rat urine after single administration of a dose calculated from the doses commonly taken by drug users. The hydroxy-mCPP metabolites should be used as target analytes being the major metabolites of mCPP. Assuming similar metabolism, our STA procedure should be suitable for detection of an intake of mCPP in human urine. Furthermore, possibilities for differentiating an intake of mCPP from that of its precursor drugs trazodone or nefazodone, two common antidepressants, are described. Within the context of these studies, N-(3-chlorophenyl)ethylenediamine was identified as a new metabolite of these two antidepressants.