Condensed 1,2,3-triazoles (review)

Methods for the synthesis of condensed 1,2,3-triazoles, including mesoionic compounds, in the literature up to 2007 inclusively are presented. They are classified according to the method by which the molecular skeleton is formed. Mesoionic condensed compounds of the 1,2,3-triazole series are examined separately. Dedicated to Academician Boris Aleksandrovich Trofimov on his seventieth jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1295–1330, September, 2008.     

Reaction of dihalocarbenes with aryl and cyclopropyl derivatives of ethylene

Conclusions The method of competitive reactions has been used to investigate the activity of p- and -substituted styrenes and 1-substituted cyclopropylethylenes in reactions with dihalocarbenes. The weakening of the influence of the substituents on the activity of the double bond with their increasing nucleophilic properties has been demonstrated, and it has been concluded that there is a single mechanism underlying the reactions of dichlorocarbene with the olefins investigated.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2292–2297, October, 1977.See also [1–3].We thank R. R. Kostikov for making some useful remarks regarding the work.     

Self condensation of enamines mediated by acetylation. A novel approach to 1-(azol-5-yl)-(1E,3Z)-butadiene-4-N,N-dimethylamines

Novel self-condensation of 3-(azol-5-yl)-1,1-dimethylenamines has been found to form new C-C bonds leading to 2,4-(1,2,3-triazole-1,2,3-thiadiazole-3-phenylisothiazole)-(1E,3Z)-5-yl-butadiene-1-amines. The discovered reaction represents a new example of C-H functionalization in unsaturated systems and can serve an efficient synthetic approach to rational design of new 2,4-(diazole-5-yl)-dieneamines.     

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 ¹H and ¹³C 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 © 2016 John Wiley & Sons, Ltd.     

Self-condensation of β-(isoxazol-5-yl) enamines under treatment with acetyl chloride and acids. Synthesis of novel 1,3-diisoxazolyl-1,3-dieneamines and 1,3,5-triisoxazolyl benzenes

Two directions for self-condensation of β-(isoxazol-5-yl) enamines under treatment with either acetyl chloride or acids were found leading to new 1,3-diisoxazolyl-1,3-dieneamines and 1,3,5-triisoxazolyl benzenes. The effect of solvent, acid, temperature and the reaction time on the ratio of reaction products were investigated. Trans-E-cis configuration of prepared 1,3-diisoxazolyl-1,3-dieneamines was unambiguously confirmed by 2D NMR spectra and X-ray analysis. A new mechanism of 1,3-diisoxazolyl-1,3-dieneamines formation was proposed.     

Interactions of bovine serum albumin with aluminum polyoxocations and aluminum hydroxide

Interactions of aqueous solutions of aluminum polyoxocations (Al13-mers and Al30-mers) and aluminum hydroxide suspensions of varying particle sizes (26, 55, and 82 nm) with a model protein, bovine serum albumin (BSA), have been investigated using potentiometry, conductometry, viscometry, 27Al solution NMR, UV-vis spectroscopy, dynamic light scattering, zeta-potential measurements, thermogravimetry, X-ray diffraction, and scanning electron microscopy. Increasing amounts of BSA partially convert Al13-mers and, to a larger extent, Al30-mers into amorphous Al hydroxide without gel formation. At the same time, BSA molecules can form unstable aggregates in the Al polyoxocation solutions which redisperse easily upon standing. In the case of Al hydroxide sols, BSA addition causes substantial gelation, the extent of which is proportional to the amount of BSA added and inversely related to the Al hydroxide particle size. Upon freeze-drying or centrifugation of Al species-BSA solutions, an interesting sheetlike morphology with 150-200 nm wide nanoribbons is observed for pure Al hydroxide nanoparticles and for solutions of Al polyoxocations with the highest amount of BSA studied. On the basis of the combined solution, colloidal and solid-state characterization of model Al species-BSA systems, a qualitative model of possible interactions in the Al polyoxocation-BSA and Al hydroxide-BSA systems is proposed wherein core-shell hybrid nanoparticles are formed from protein "core" and Al polyoxocation "shell" or Al hydroxide "core" and protein "shell".     

A novel miniature cell retainer for correlative high-content analysis of individual untethered non-adherent cells

The importance of research involving non-adherent cell lines, primary cells and blood cells is generally undisputed. However, the task of investigating the complexity and heterogeneity of these cells calls for their long-run monitoring at a single-cell resolution. Such a capability is currently unavailable without having to use disruptive cell tethering. The present Cell Retainer (CR) concept enables high-content correlative multi-parametric measurements, from the functional to molecular level, of the same living individual non-adherent cells within a population. Thereby, despite extensive long-term bio-manipulations, the cells preserve their identity without tethering. Several exemplary experiments, using a microscope-slide-based version of the CR, are presented, which could not be performed by other state of the art methods.