Diselenide exchange is introduced as a reversible reaction in dynamic combinatorial chemistry in water. At neutral pH, diselenides are found to mix with disulfides and form dynamic combinatorial libraries of diselenides, disulfides, and selenenylsulfides.
Recently, semi-synthetic cannabinoids have entered the illegal market and are produced to mimic the psychoactive effects of tetrahydrocannabinol (THC). This is a case report of a 19-year-old man, who was hospitalized due to severe sedation, hypotension and tachy- and bradycardia after ingestion of the semi-synthetic cannabinoids hexahydrocannabinol (HHC) and hexahydrocannabiphorol (HHC-P) mixed in food. HHC-P, HHC and metabolites were identified in blood samples. The amount of semi-synthetic cannabinoids in illegal products can be high, which can explain the described prolonged clinical effects.
Illicit drug profiling performed by forensic laboratories assists law enforcement agencies through providing information about chemical and/or physical characteristics of seized specimens. In this article, a model was developed for the comparison of seized cocaine based on retrospective analysis of data generated from ultrahigh performance liquid chromatography with time-of-flight mass spectrometry (UHPLC-TOF-MS) comprehensive drug screening. A nontargeted approach to discover target compounds was employed, which generated 53 potential markers using data from cocaine positive samples. Twelve marker compounds were selected for the development of the final profiling model. The selection included a mixture of commonly used cocaine profiling targets and other cocaine-related compounds. Combinations of pretreatments and comparison metrics were assessed using receiver operating characteristic curves to determine the combination with the best discrimination between linked and unlinked populations. Using data from 382 linked and 34,519 unlinked distances, a classification model was developed using a combination of the standardization and normalization transformations with Canberra distance, resulting in a linked cut-off with a 0.5% false positive rate. The present study demonstrates the applicability of retrospectively developing a cocaine profiling model using data generated from UHPLC-TOF-MS nontargeted drug screening without pre-existing information about cocaine impurities. The developed workflow was not specific to cocaine and thus could potentially be applied to any seized drug in which there are both sufficient data and impurities present.
Herein we showcase the use of a combination of 1H, 13C, and 77Se NMR spectroscopy as a sensitive tool for correlation analysis. A series of substituted O-aryl selenocarbamates [ArOC(Se)N(CH3)2] and Se-aryl selenocarbamates [ArSeC(O)N(CH3)2] have been investigated by means of 1H, 13C, and 77Se NMR spectroscopy. We have determined the 1H, 13C, and 77Se chemical shift values as well as both one- and two-bond heteronuclear 13C–77Se coupling constants, and the changes in both the chemical shift values and the coupling constants were found to obey linear free energy relationships with Hammett's σp and σp– constants. For the eight studied O-aryl selenocarbamates, we observe linear free energy correlations with two of the 13C and 77Se chemical shift values and as well as one 13C–77Se coupling constant. With the five examples of Se-aryl selenocarbamates, linear correlations are observed with three different 13C–77Se coupling constants. The strong internal consistency validates the use of 77Se NMR spectroscopy for correlation analysis.
Systematic toxicological analysis (STA) is the process of using an adequate analytical methodology to detect and identify as many potentially toxicologically relevant compounds as possible in biological samples. STA is an important part of everyday routine work within forensic toxicology, and several methods for STA have frequently been published and reviewed independently. However, the many drugs and other substances involved, as well as the constant emergence of new ones, may pose a major challenge in STA, which often demands a strategy involving multiple analytical methods in parallel. Such strategies have been published and evaluated less frequently despite their relevance in forensic toxicology. This mini-review briefly summarizes commonly applied methods for STA in forensic toxicology, including gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-MS (LC-MS) methods, and highlights some of their potential pitfalls. Second, it provides an overview of previously reported strategies to conduct STA, including a presentation of the STA strategy applied in the authors' laboratory. This involves broad drug screening by LC-high-resolution MS, supported by targeted screening and quantification using LC-tandem MS, headspace (HS)-GC-MS, HS-GC-flame ionization detector and other complementary methods. The STA strategy aims to cover as many potentially relevant drugs as possible and seeks to reduce potential pitfalls arising in forensic casework. The review underlines that not every substance can be identified in all circumstances even with a comprehensive STA strategy.