Oleg S. Eltsov

Analytical characterization of some synthetic cannabinoids, derivatives of indole-3-carboxylic acid

By means of gas chromatography with high resolution mass spectrometry (GC-HRMS), ultra-high performance liquid chromatography in combination with high resolution tandem mass spectrometry (UHPLC-HRMS), nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared spectroscopy (FT-IR), structure of a series from a novel synthetic cannabinoids, derivatives of indole-3-carboxylic acid, was established. Methods for determination of the compounds in mixtures, involving chromatographic separation with mass-spectroscopic determination, were elaborated. Analytical data obtained in the paper will make reliable identification of synthetic cannabinoids of the new type during forensic examination possible.

Identification and analytical characteristics of synthetic cannabinoids with an indazole-3-carboxamide structure bearing a N-1-methoxycarbonylalkyl group

Illicit new psychoactive substances (NPS) are a serious threat to health throughout the world. Such NPS do not usually pass preliminary pharmacological trials. In 2014, we identified a series of five new synthetic cannabinoids with an indazole-3-carboxamide structure bearing an N-1-methoxycarbonylalkyl group. The compounds have very high cannabimimetic activity which has caused mass severe intoxication and deaths. The compounds were identified by means of gas chromatography–mass spectrometry (GC–MS), including high-resolution mass spectrometry (GC–HRMS), ultra-high-performance liquid chromatography–high-resolution tandem mass spectrometry (UHPLC–HRMS2), and 1H and 13C nuclear magnetic resonance spectroscopy (NMR). The peculiarities of mass-spectral fragmentation of the compounds after electron ionization (EI) ionization and collision-induced dissociation (CID) were studied. The analytical characteristics reported for the compounds will enable their identification in a variety of materials seized from criminals.Graphical Abstract

Synthetic cannabinoids as designer drugs: New representatives of indol-3-carboxylates series and indazole-3-carboxylates as novel group of cannabinoids. Identification and analytical data

By means of gas chromatography with mass spectrometry detection (GC-MS), including high resolution mass spectrometry (GC-HRMS) together with ultra-high performance liquid chromatography in combination with high resolution tandem mass spectrometry (UHPLC-HRMS), nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared spectroscopy (FT-IR), structure of new synthetic cannabinoids, representatives of indol- and indazole-3-carboxylates groups, used in smoke mixtures, was determined. Obtained analytical data make reliable identification of these compounds in a course of analysis of criminal seizures possible.

3-Naphthoylindazoles and 2-naphthoylbenzoimidazoles as novel chemical groups of synthetic cannabinoids: Chemical structure elucidation, analytical characteristics and identification of the first representatives in smoke mixtures

By means of gas chromatography with mass spectrometry detection (GC-MS), including high resolution mass spectrometry (GC-HRMS) together with ultra-high performance liquid chromatography in combination with high resolution tandem mass spectrometry (UHPLC-HRMS), nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared spectroscopy (FT-IR), structure of novel synthetic cannabinoids, namely, 1-(5-fluoropentyl)-1H-indazol-3-yl(naphthalen-1-yl)methanone, naphthalen-1-yl(1-pentyl-1H-benzo[d]imidazol-2-yl)methanone and 1-(5-fluoropentyl)-1H-benzo[d]imidazol-2-yl(naphthalen-1-yl)methanone was established. Analytical data obtained in the paper enable reliable identification of these compounds during qualitative analysis of seizures, including smoke mixtures.

Synthetic cannabinoid 3-benzyl-5-[1-(2-pyrrolidin-1-ylethyl)-1H-indol-3-yl]-1,2,4-oxadiazole. The first detection in illicit market of new psychoactive substances

We were the first to detect 3-benzyl-5-[1-(2-pyrrolidin-1-ylethyl)-1H-indol-3-yl]-1,2,4-oxadiazole (given name BzODZ-EPyr) as a new synthetic cannabinoid, in illegal market of new psychoactive compounds (NPS). The compound was known only from pharmaceutical literature so far. BzODZ-EPyr was identified by means of gas chromatography/mass spectrometry (GC/MS) including high resolution mass spectrometry (GC/HRMS), ultra-high performance liquid chromatography/high resolution tandem mass spectrometry (UHPLC/HRMS(2)), Fourier-transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR) (1)H and (13)C. The peculiarities of mass-spectral fragmentation in experiments in electronic ionization (EI) and collision-induced dissociation (CID) modes were studied. Herewith we report analytical characteristics of BzODZ-EPyr enabling its (and possible analogues thereof) determination in criminal seizures.

NON-NATURAL NUCLEOSIDES BASED ON 1,2,4-TRIAZOLO[1,5-a]PYRIMIDIN-7-ONES

Two methods for synthesis of new nucleosides bearing 6-phenyl-1,2,4-triazolo[1,5-a]pyrimidin-7-ones as a base have been developed. The first one includes Vorbruggen glycosylation reaction. The second method, which is effective for synthesis of acyclic nucleosides, is based on the condensation between sodium salts of 6-phenyl-1,2,4-triazolo [1,5-a]pyrimidin-7-ones and 4-bromobuthyl acetate or (Z)-4-bromobut-2-en-1-yl acetate.

Switchable Synthesis of 4,5-Functionalized 1,2,3-Thiadiazoles and 1,2,3-Triazoles from 2-Cyanothioacetamides under Diazo Group Transfer Conditions

High yield solvent-base-controlled, transition metal-free synthesis of 4,5-functionalized 1,2,3-thiadiazoles and 1,2,3-triazoles from 2-cyanothioacetamides and sulfonyl azides is described. Under diazo transfer conditions in the presence of a base in an aprotic solvent 2-cyanothioacetamides operating as C-C-S building blocks produce 5-amino-4-cyano-1,2,3-thiadiazoles exclusively. The use of alkoxide/alcohol system completely switches the reaction course due to the change of one of the reaction centers in the 2-cyanothioacetamide (C-C-N building block) resulting in the formation of 5-sulfonamido-1,2,3-triazole-4-carbothioamide sodium salts as the only products. The latter serve as good precursors for 5-amino-1,2,3-thiadiazole-4-carboximidamides, the products of Cornforth-type rearrangement occurring in neutral protic medium or under acid conditions. According to DFT calculations (B3LYP/6-311+G(d,p)) the rearrangement proceeds via intermediate formation of a diazo compound, and can be catalyzed by acids via the protonation of oxygen atom of the sulfonamide group.

Mass spectrometric properties of N-(2-methoxybenzyl)-2-(2,4,6-trimethoxyphenyl)ethanamine (2,4,6-TMPEA-NBOMe), a new representative of designer drugs of NBOMe series and derivatives thereof.

Emergence of new psychoactive substances, hallucinogenic phenethylamines in particular, in illicit market is a serious threat to human health in global scale. We have detected and identified N-(2-methoxybenzyl)-2-(2,4,6-trimethoxyphenyl)ethanamine (2,4,6-TMPEA-NBOMe), a new compound in NBOMe series. Identification was achieved by means of gas chromatography/mass spectrometry (GC/MS), including high-resolution mass spectrometry with tandem experiments (GC/HRMS and GC/HRMS2 ), ultra-high performance liquid chromatography/high-resolution mass spectrometry with tandem experiments (UHPLC/HRMS and UHPLC/HRMS2 ), and 1 H and 13 C nuclear magnetic resonance spectroscopy. The peculiarities of fragmentation of the compound under electron ionization (EI) and collision-induced dissociation were studied. Despite of the empirical rule denying migration of the hydrogen atom in McLafferty rearrangement to the benzene ring with substituents in the both ortho-positions, it easily occurs for 2,4,6-TMPEA-NBOMe in EI conditions. We have noticed that electron-donating substituents, e.g. methoxy groups in the both ortho-positions and para-positions favor the rearrangement. For specially synthesized N-methyl and N-acyl derivatives McLafferty rearrangement is not observed. N-Acyl derivatives demonstrate McLafferty rearrangement, but the charge retains at the alternative fragment involving N-acyl carbonyl group. We have also showed that the hydrogen atoms in 2,4,6-trimethoxybenzene ring may be easily substituted for deuterium or for strong electrophiles like trifluoroacetyl. Analytical characteristics of 2,4,6-TMPEA-NBOMe and of some derivatives thereof which enable their determination in various criminal seizures are given. Copyright

ANRORC process in 1-alkylazolo[5,1-c][1,2,4]triazin-4(1H)-ones

Nucleophilic substitution of nitro group in 1-alkylazolo[5,1-c][1,2,4]triazin-4(1H)-ones proceeds according to the ANRORC mechanism, involving the opening of azine ring, nucleophilic substitution, and cyclization. The structures of all intermediates were confirmed by spectral data.

Synthesis of dithienoquinazolines from pyrimidines via intramolecular nucleophilic aromatic substitution of hydrogen

The possibility of intramolecular nucleophilic aromatic substitution of hydrogen in the series of 5-[2-(het)aryl-1-benzothiophen-3-yl]-pyrimidines was explored. A convenient method for the synthesis of [1]benzothieno-[3,2-f]thieno[2,3-h]quinazoline and [1]benzothieno-[3,2-f]thieno[3,2-h]quinazoline based on the developed SNH protocol was proposed. The energy parameters (width of the band gap, the energy of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbitals (LUMO)) of benzothieno[3,2-f]-thieno[2,3-h]quinazoline synthesized for the first time were determined based on the data of the absorption spectra and cyclic voltammetry.