Synthesis, full chemical characterisation and development of validated methods for the quantification of the components found in the evolved “legal high” NRG-2

The recent global increase in the abuse of 4′-methylmethcathinone (mephedrone) and related compounds has developed a requirement for full chemical characterisation of these products. This work presents full synthetic and chemical characterisation data for the hydrobromide salts of two mephedrone derivatives: 4′-methyl-N-ethylcathinone (4-MEC) and 4′-methyl-N-benzylcathinone (4-MBC) which have been identified in samples of the “legal high” NRG-2. The first fully validated chromatographic methods for the detection and quantitative analysis of these substances both in their pure form and in the presence of a number of common adulterants used in illicit drug manufacture is also reported.

Graphical abstractThe prevalence of these cathinone-derived “legal high” drugs has given rise to both legal and analytical challenges in the identification of these substances. Full chemical characterisation and robust HPLC methods for the determination of two new derivatives of mephedrone (namely 4-MEC and 4-MBC) identified in “street” samples of NRG-2 is presented.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Synthesis of two (±)-mephedrone derivatives: (±)-4′-methyl-N-ethylcathinone (4-MEC) and (±)-4′-methyl-N-benzylcathinone (4-MBC) identified in samples of NRG-2. ► Full and comprehensive analytical profiling of 4-MEC and 4-MBC. ► Fully validated chromatographic methods for the analysis of 4-MEC and 4-MBC in their pure form and in the presence of common adulterants. ► Evaluation of sourced samples of NRG-2.