Analysis of synthetic cannabinoids in "spice-like" herbal highs: snapshot of the German market in summer 2011

In this study, seven commercial "spice-like" products available on the German market were analyzed. They all contained significant amounts of synthetic cannabinoids and had distinctly different compositions of these adulterants. All synthetic cannabinoids were extracted and purified by different chromatographic techniques from the respective product. The structures of all compounds were elucidated by nuclear magnetic resonance spectroscopy and further characterized by mass spectrometry (MS) and ultraviolet and infrared spectroscopy to generate a full data set of each compound. Altogether, eight compounds were identified, and one deuterium-labeled cannabinoid was used as internal standard. Four products contained only one individual compound, while three products contained mixtures of two compounds. Among the eight isolated compounds, six were already known from recent publications (JWH-081, JWH-210, JWH-122, AM2201, RCS-4, and JWH-203), but the published data were not always complete. In addition, two unknown compounds (AM2201-pMe, RCS-4-(N-Me)) were isolated. Overall, compounds from three distinct classes of synthetic cannabinoids could be identified, characterized, and compared. The MS data of the different subclasses allowed the postulation of some general key fragmentations to distinguish between these subclasses. In addition, we established a general method using an isotopically labeled internal standard (JWH-018-D-3) to quantify synthetic cannabinoids in herbal mixtures. The total content of the synthetic cannabinoids ranged from 77.5 to 202 mg/g, while individual compounds were detected from 19.3 to 202 mg/g in these products. The spectroscopic data for all compounds mentioned here were collected and added en bloc as Electronic supplementary material to this manuscript.