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Azoloazine derivatives are known as promising small molecules that are potentially able to counteract a broad spectrum of RNA viruses including SARS‐CoV‐2. However, a pool of synthetic pathways to provide convenient structural modification of such compounds without de novo construction of the heterocyclic scaffold is rather limited so far. This work proposes an approach to the direct C(sp2)−H functionalization of azolopyrimidine substrates with aromatic thiol residues, mediated by the iodine/persulfate reagent system. The reported herein sulfenylation protocol has afforded a series of previously undescribed azolopyrimidine‐based thioethers obtained in yields of up to 87 %. Applicability of the approach to the selenium‐centered synthons has been demonstrated as well. Besides, the in silico study with regard to the achieved cross‐coupling products has suggested the possible affinity to the SARS‐CoV‐2 main protease (Mpro), as follows from the conducted pharmacophore search and the molecular docking experiments. As a result, the developed synthetic transformation is expected to be of utility in the design of novel antiviral agents based on small azaheterocyclic molecules. [ABSTRACT FROM AUTHOR]

The article discusses the methods of multi-criteria assessment of the efficiency of vehicle operation according to their properties. The main difficulties in solving the issue of technical operation of vehicles when introducing these methods into the assessment process are highlighted. Algorithms of decision-making related to the choice of a vehicle in conditions of uncertainty of the external environment are analyzed. Their advantages and disadvantages are substantiated. A methodology for calculating weight coefficients for the optimization and development of the transport system is proposed.

The article presents a comprehensive method for removing uncertainty when solving multicriteria problems of vehicle maintenance. The task of the control system for the service life of the car is formed, and its characteristics are also highlighted. The main provisions of the zoning method are formulated from the point of view of the hierarchical correlation of the probabilities of the state of the external environment. The dynamics of changes in the quality indicators of cars in a multicriteria setting is estimated.

An original approach to achieve the C(sp2)–H azolation of cyclic aldonitrones mediated by Selectfluor® has first been employed. By exploiting a metal-free, visible-light-promoted cross-dehydrogenative C–N coupling reaction between model aldonitrones, 2H-imidazole 1-oxides, and NH-containing azoles, a series of novel azaheterocyclic derivatives have been obtained in yields up to 94%. The elaborated protocol has proved to be appropriate for gram-scale processes and displayed potential for utilization in the synthesis of novel structural analogues of lanabecestat. Besides, mechanistic studies have revealed that this coupling reaction is likely to proceed via a nitroxide-involving radical pathway, encompassing a chain of electron transfer events, such as hydrogen atom transfer (HAT) and single electron transfer (SET). [ABSTRACT FROM AUTHOR]

Direct C(sp2)-H functionalization of the endocyclic azomethine and aldonitrone moieties in non-aromatic azaheterocycles has established itself as a promising methodology over the last decade. Transition metal-catalyzed cross-coupling reactions, α-metalation-electrophile quenching protocols, and (metal-free) nucleophilic substitution of hydrogen reactions (SNH) are the major routes applied on cyclic imines and their derivatives. In this overview, we show the tangible progress made in this area during the period from 2008 to 2020.

The C(sp 2 )-H bond functionalization methodology was first applied to carry out the palladium-catalyzed oxidative C-H/C-H coupling reactions of 2 H -imidazole 1-oxides with pyrroles and thiophenes. As a result, a number of novel 5-heteroarylated 2 H -imidazole 1-oxides, which are of particular interest in the design of bioactive molecules and advanced materials, have been synthesized in yields up to 78%. The detailed H/D-exchange experiments have also been performed to elucidate some mechanistic features of this cross-dehydrogenative coupling process., Competing Interests: The authors declare no competing financial interest.