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The reaction of 1-vinyl-4,5-dihydro-1H-benzo[g]indole with C-aryl-N-methylnitrones in the presence of nickel (II) perchlorate proceeds regioselectively to form a mixture of diastereomeric adducts of formal (3+3) cycloaddition, whereas the main products of the reaction with C,N-diarylnitrones are dipyrromethanes. [ABSTRACT FROM AUTHOR]

The symposium on the chemistry of alkynes, allenes, and small rings was held on July 3–6, 2023 at St. Petersburg State University as part of the All-Russian conference with international participation "Ideas and Legacy of A.E. Favorsky in Organic Chemistry." Leading experts in the chemistry of alkynes, allenes, and small rings took part in the conference, recent advances in the chemistry of compounds of these classes were presented, and prospects for further development of this research field were discussed. Brief annotations of the reports made and references to the relevant publications of the authors are collected in the present review. [ABSTRACT FROM AUTHOR]

New 5-ethynylisoxazoles were obtained via 1,3-dipolar cycloaddition reactions of nitrile oxides with buta-1,3-diynes. The cycloaddition proceeds regioselectively by the terminal triple bond. [ABSTRACT FROM AUTHOR]

The VIth International Symposium "The Chemistry of Diazo Compounds and Related Systems" (DIAZO 2021) was held at the St. Petersburg State University from 6 to 10 September 2021. At the symposium, the advances in diazo chemistry over the past decade were summed up, and promising directions for further research were discussed. The review contains brief annotations of the plenary, keynote, invited and oral presentations and includes references to the relevant works of the speakers. [ABSTRACT FROM AUTHOR]

We demonstrated the possibility of penetration of magnetite-gold nanoparticles conjugated with prostate-specific membrane antigen into mouse macrophages. It was found that after 3-h incubation with nanoparticles in a concentration of 15 mg/liter at 37oC, they were seen in only 13% macrophages. In about 90% cells, the nanoparticles were detected within the cytoplasm. Under these conditions, membrane damage was revealed in 25% cells. These results should be taken into account in further development and application of nanomaterials for diagnostic and therapeutic purposes in oncology. [ABSTRACT FROM AUTHOR]

We demonstrated the possibility of penetration of magnetite-gold nanoparticles conjugated with prostate-specific membrane antigen into mouse macrophages. It was found that after 3-h incubation with nanoparticles in a concentration of 15 mg/liter at 37oC, they were seen in only 13% macrophages. In about 90% cells, the nanoparticles were detected within the cytoplasm. Under these conditions, membrane damage was revealed in 25% cells. These results should be taken into account in further development and application of nanomaterials for diagnostic and therapeutic purposes in oncology. [ABSTRACT FROM AUTHOR]

Thermal addition of aldonitrones (C,N-diaryl- and N-aryl-C-arylcarbamoylnitrones) to the double bond of N-phenyl-9,10-dihydro-9,10-ethenoanthracene-11,12-dicarboximide yields heteropropellanes containing isoxazolidine and pyrrolidine fragments. The cycloaddition of C,N-diarylnitrones is stereoselective, and only one diastereoisomer is formed. [ABSTRACT FROM AUTHOR]

1,3-Dipolar cycloaddition of nitrile oxides and nitrones to N-vinylindole proceeds regioselectively at the exocyclic multiple bond to form 5-indolyl-substituted isoxazolines and isoxazolidines in good yields. [ABSTRACT FROM AUTHOR]

Nitrones cycloaddition to 1-vinyl-4,5-dihydro-1 H-benzo[ g]indole proceeds regio- and steroselectively affording a single diastereomer of 5-(hetaryl-substituted)isoxazolidine. [ABSTRACT FROM AUTHOR]

The importance of developing GOST standard specifications for the quality control of different grades of synthetic rubber produced in Russia, incorporating standard elastic strength and rheometric characteristics, is shown. Here, ISO and ASTM test procedures must be used, as well as positive features of Russian technical documentation. The need for and the possibility of producing and certifying home-produced reference ingredients and carbon black are also shown. The creation of a unified base of reference materials (ingredients, carbon black, etc.) will make it possible to increase the reliability of product quality control at synthetic rubber, tyre, and mechanical rubber goods plants. [ABSTRACT FROM AUTHOR]

• Healthy and cancerous cells were subjected to the action of the magnetic nanoparticles and fields. • The new approach of magnetically activated antileukemia therapy was suggested. • Magnetic field enhances cytotoxicity of iron oxide magnetic nanoparticles. • Cancerous cells are more affected by combining the action of magnetic nanoparticles and fields. This paper describes proof-of-concept for antileukemia treatment based on the reactive oxygen species (ROS) induction supplemented with magnetic nanoparticles in the presence of moderate-intensity magnetic fields. The T-lymphoblastic leukemia cell line (Jurkat) was chosen as an in vitro model of acute lymphoblastic leukemia. The elevated ROS levels were generated by iron oxide magnetic nanoparticles. We found an enhanced cytotoxic effect of magnetic nanoparticles in the presence of a magnetic field on cancerous Jurkat cell line due to induced oxidative stress after cultivation in magnetic fields with an average strength of 0.26–0.36 T and the field spatial gradient up to 100 T/m. At the same conditions of nanoparticles intake, the viability of human peripheral blood mononuclear cells (model of healthy cells) was not inhibited. Thus, we demonstrated the feasibility of antileukemia treatment by magnetic nanoparticles controlled by a magnetic field. [ABSTRACT FROM AUTHOR]

A new approach to the control of biochemical reactions in magnetic nanosuspensions exposed to a low-frequency (nonheating) magnetic field, which has a nanomechanical effect on macro-molecules chemically linked to magnetic nanoparticles (MNPs), is described. Experimental verification of this approach showed that a magnetic field with an intensity of from 15 to 220 kA/m and a frequency of 50 Hz affected the kinetics of a chemical reaction in an aqueous solution containing suspended MNPs of magnetite (FeO · FeO) and chymotrypsin molecules linked to them through polymer bridges. The field dependence of the effect is shown. The effect is interpreted within the framework of a nanomechanical model taking into account the deformations, conformational change, and destruction of weak bonds in the enzyme macromolecule under the action of the forces applied to it during the orientation of MNPs in the field. [ABSTRACT FROM AUTHOR]