Abstract
5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT) has hallucinogenic activity and has been prohibited by the Narcotics and Psychotropics Control Law in Japan since April 2005. In general, to prove of drug ingestion, the urine is the most popular and effective sample for the analysis, because it is easy to collect and the parent drug and its metabolites are relatively concentrated in it. Therefore, it is very important to identify the metabolites in urine. But with respect to 5-MeO-DIPT, the investigation about its metabolites has not been performed sufficiently.
In this paper, with the aim of detecting basic metabolites, 5-MeO-DIPT and related compounds were extracted from the abuser's urine which had been stored at -20°C for about 2 years, with liquid-liquid extraction under alkaline condition and solid-phase extraction using two types of cartridges (reversed-phase, Oasis® HLB and mixed-mode, Oasis® MCX), and analyzed by gas chromatography/mass spectrometry (GC/MS). Although slight decomposition may have occurred during storage, 5 related compounds were detected and the structures of these compounds were presumably identified.
5-Hydroxy-N,N-diisopropyltryptamine and 5-methoxy-N-isopropyltryptamine were detected as the main metabolites with the parent drug, 5-MeO-DIPT. The concentration of 5-MeO-DIPT was measured to be 1.1 μg/ml when the drug was extracted with Oasis® MCX. In addition, the trace amounts of 2 related compounds which were thought to be 5-hydroxy-N-isopropyltryptamine and 6-hydroxy-5-methoxy-N,N-diisopropyltryptamine-N'-oxide were detected. Furthermore, one metabolite which was assumed to be 5-methoxy-N,N-diisopropyltryptamine-N'-oxide in the reference paper was suggested to be 6-hydroxy-5-methoxy-N,N-diisopropyltryptamine, judging from the results of the extraction behavior.
