Gas chromatography/mass spectrometry analysis of the six-ring regioisomeric dimethoxybenzyl-N-methylpiperazines (DMBMPs)

• NCJ Number: 307075
• Journal: Rapid Communications in Mass Spectrometry Volume: 27 Issue: 22 Dated: 2013 Pages: 2551-2558
• Author(s): Karim M. Abdel-Hay; Jack DeRuiter; C. Randall Clark
• Date Published: 2013
• Length: 8 pages
• Grant Number(s): 2011-DN-BX-K530
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical)
• Award: Analytical and Synthetic Studies on Designer Drugs of the Piperazine Class This project will address issues of resolution and discriminatory capabilities in controlled substance analysis.

Annotation

The authors of this paper explore the electron ionization mass spectrometric fragmentation of the dimethoxybenzyl-N-methylpiperazines as potential designer modifications of the general benzylpiperazine drug skeleton, along with the gas chromatography properties of all six of the regioisomeric substances.

Abstract

Piperazine-based designer drugs represent a novel class of substances found in illicit drug samples in the US and abroad. The clandestine production of these substances often makes use of piperazine as a key commercially available precursor substance. The commercial availability of 1-methylpiperazine suggests additional designer modification based on this additional precursor material. This study focuses on the electron ionization mass spectrometric (EI-MS) fragmentation of the dimethoxybenzyl-N-methylpiperazines as potential designer modifications of the general benzylpiperazine drug skeleton and explores the gas chromatography (GC)/MS properties of all six of these regioisomeric substances. Fragmentation of the bond between the benzylic carbon and the adjacent piperazine nitrogen provides the base peak in all six spectra. The internal fragmentation within the piperazine ring produces a number of unique ions in the mass spectra of these dimethoxybenzyl-N-methylpiperazines. The migration of methyl groups from nitrogen and oxygen were confirmed by deuterium-labeling experiments. The six regioisomeric dimethoxybenzyl-N-methylpiperazines yield equivalent fragment ions and deuterium labeling confirmed the elemental composition of the characteristic fragments in their mass spectra. Mixtures of the dimethoxybenzyl-N-methylpiperazines were successfully resolved via capillary gas chromatography using a relatively polar stationary phase and temperature-programming conditions. (Publisher Abstract Provided)