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A series of (η6-arene)tricarbonylchromium derivatives of 1,4-dihydro-3,1-benzoxazines was synthesized and characterized. The compounds were obtained by two alternative methods, namely, by the reaction of triammine(tricarbonyl)chromium with 1,4-dihydro-3,1-benzoxazines (method A) and by the condensation of (η6-2-aminobenzyl alcohol)tricarbonylchromium with various aldehydes and ketones (method B). The composition and structure of obtained compounds were established by different physicochemical methods of analysis, such as HPLC, UV, IR, 1H NMR spectroscopy, mass spectrometry, and X-ray diffraction.

The effect of conjugated dinitrones N,N-dimethylglyoxaldinitrone, N,N-di-tert-butylglyoxaldinitrone, and N,N-diphenylglyoxaldinitrone on the radical polymerization of styrene initiated by azobis(isobutyronitrile) is studied. It is found that, during the polymerization of styrene at temperatures below 90°C, chains terminate on the studied nitrones to generate high molecular weight nitroxide radicals. The regularities of polystyrene synthesis in the presence of conjugated nitrones at 130°C (the first reaction order with respect to the monomer over the entire conversion range, a linear increase in molecular weight with conversion, and postpolymerization) indicate that the polymerization of styrene can be implemented under reversible inhibition conditions in the high temperature regime. It is shown that the acceptance and specific features of styrene polymerization mediated by nitroxide radicals formed in situ are directly related to the initial structure of dinitrones. For example, the presence of conjugation between phenyl and nitronyl groups in diphenyl dinitrone leads to a decrease in its accepting ability, lowering the effectiveness of high molecular weight nitroxides as polymerization regulators in the high temperature mode. Using the methods of static and dynamic light scattering, the hydrodynamic sizes of macromolecules are estimated and the form factor Rg/Rh of a linear polymer and polymers synthesized with the participation of dinitrones is calculated.

Experimental and experimental–theoretical studies (using the molecular invariom) of the electron density distribution are performed for the η6-[3-acetyltetrahydro-6-phenyl-2Н-1,3-oxazine]tricarbonylchromium(0) complex. The topological characteristics of the electron density (ρ(r), ∇2ρ(r)) at the critical points (3, –1) coincide in the experimental and experimental–theoretical distributions within the “transferability indices.” The experimental–theoretical study more reliably localizes the “expected” critical points (3, –1) between the chromium atom and arene ligand.

The condensation reactions of β- and γ-amino alcohols containing phenyl or (η6-arene) tricarbonylchromium substituent with formaldehyde, acetaldehyde, benzaldehyde, and (η6-benzaldehyde)tricarbonylchromium were studied. The resulting 1,3-oxazolidine and 1,3-oxazinane products were isolated in a pure form and identified by different physicochemical methods. The effect of (η6-arene)tricarbonylchromium moiety on the reaction process was demonstrated.

An approach based on the simultaneous use of a source function and a noncovalent interaction index for studying interatomic interactions in the absence of bond critical points is offered. This approach comprises the selection of reference points for the source function on the noncovalent interaction index isosurface.

The reactions of 1,3-dipolar cycloaddition of π-complexes of nitrones of a general formula R2CH=N(O)R1, where R1 = Me, But, Ph, R2 = Ph[Cr(CO)3], C5H4[Mn(CO)3] with (η6-styrene)-tricarbonylchromium and vinyl-(η5-cyclopentadienyl)tricarbonylmanganese have been investigated. These reactions led to the formation of corresponding isoxazolidines with high regio- and diastereoselectivity. The obtained metal-containing isoxazolidines were identified using UV, IR, 1H NMR spectroscopy, mass-spectrometry, and X-ray diffraction analysis.

1,3-Dipolar cycloaddition reactions of nitrones of general formula R2CH=N(O)R1, where R1 = Me, But, Ph, R2 = Ph, Cp[Mn(CO)3] with styrene and vinyl-η5-(cyclopentadienyl) manganese tricarbonyl were studied. The products of these reactions, i.e., isoxazolidines, were isolated, purified, and identified. A high selectivity of the cycloaddition reactions involving both dipoles and dipolarophiles containing cyclopentadienylmanganese tricarbonyl group was demonstrated.

Charge distribution and frontier orbital energies of styrene, C,N-diphenylnitrone, and their (arene)-(tricarbonyl)chromium complexes were calculated by quantum chemical methods. The difference in the HOMO and LUMO energies of the chromium complexes was found to be smaller than in the free ligands, and the reactions with (arene)(tricarbonyl)chromium complexes were characterized by higher rate and selectivity.

The reactions of nitrones of the composition (CO)3CrC6H5CH=N+(O−)R (R = Me, Ph, or But) with substituted acetylene were studied. The reactions proceed with high regioselectivity and give 4-isoxazolines (yields 50–60%). The composition and structures of these products were characterized by physicochemical methods. The reactions also afford (η6-benzaldehyde)tricarbonylchromium, coordinated Schiff bases, and azoxy derivatives as thermal decomposition products of the starting nitrones. The reactions of uncoordinated nitrones with methyl phenylpropiolate were also investigated. These reactions produce 4-isoxazolines along with cyclic substituted isoxazolinones.

A new synthetic route to trimethylgallium was developed. It is based on preparation of gallium methyl derivatives by the Green reaction, followed by their alkylation with methyl Grignard reagent. The suggested procedure is well reproducible, with the yield of pure trimethylgallium exceeding 90%.

The products of 1,3-dipolar cycloaddition of the nitrone-type η6-(arene)chromium tricarbonyl complexes (CO)3CrC6H5CH=N+(O−)R, where R = Me, Ph, But, with styrene and η6-(styrene)chromium tricarbonyl were obtained and characterized by a combination of physicochemical methods. This type of reactions proceeded with very high regio- and stereoselectivity to exclusively form cis-2,3,5-tri-substituted isoxazolidines.

The 1,3-dipolar cycloaddition products of C,N-disubstituted nitrones and different in situ prepared mono-N-substituted nitrones to η6-(styrene) chromium tricarbonyl and η6-(ethyl cynnamate) chromium tricarbonyl were synthesized and characterized by HPLC, IR, 1H NMR spectroscopy, and mass spectrometry. The resulted isoxazolidines were produced with a full regioselectivity and high stereoselectivity reached 100% in most cases.

Cycloaddition of η6-(styrene)chromium tricarbonyl to hexa-2,4-diene or cyclopentadiene afford the Diels-Alder adducts with retention of the Cr(CO)3 group, whereas cyclohexa-1,3-diene undergoes aromatization to give η6-(benzene)chromium tricarbonyl. The counter synthesis of these (arene)chromium tricarbonyl derivatives from uncoordinated adducts of the Diels-Alder reaction and chromium hexacarbonyl was carried out.

We studied the in vitro apoptosis-inducing effect of recombinant TNF-α (rTNF-α) on blood lymphocytes from healthy donors. rTNF-α-induced apoptosis was accompanied by an increase in the number of cells with low mitochondrial transmembrane potential, increased intracellular content of reactive oxygen species, reduced content of Bcl-2, Bcl-xL, and Bax proteins, and elevated Bad content. The molecular mechanisms of these changes are discussed.

The effect of recombinant TNF-α on programmed death of donor lymphocytes was studied in vitro. The proapoptotic effect of this cytokine is realized through transcription factors and cell cycle inhibitors. Incubation of lymphocytes with recombinant TNF-α revealed increased levels of NF-kB and p21 and reducted content of nonphosphorylated p53.

Heterogeneous hydrogenation of the styrene and stilbene chromium tricarbonyl complexes by molecular hydrogen on skeletal nickel and palladium on carbon as catalysts was studied. As compared to styrene and stilbene, their arene chromium tricarbonyl analogs are hydrogenated considerably more slowly, which is related, most likely, to strong adsorption of the π-complexes on the catalyst surface. For the homogeneous hydrogenation of these complexes using a H2PtCl6-SnCl2-LiBr system, styrene and η6-styrene chromium tricarbonyl are reduced with a high rate, whereas stilbene and its chromium tricarbonyl complex are hydrogenated very slowly. A possibility of reduction of the unsaturated arene chromium tricarbonyl complexes by sodium borohydride in the presence of cobalt(II) chloride as a catalyst was shown.

Detectors were created for dosimetry of 60 Co γ- and proton radiations and the γ-component of reactor radiation based on KI glasses fused from the quartz of the Volyn deposit. The absorbed dose within the dose interval of 10 to 5 × 10 3 Gy can be measured by the thermoluminescence (TL) intensity and within the interval of 5 × 10 3 to 2 × 10 5 Gy can be done by the induced optical density at 550 nm. Detectors based on the quartz glasses KV and KU-1, measuring the absorbed dose by the induced optical density at 215 nm, were proposed for the γ-radiation dose interval from 5 × 10 5 to 10 8 Gy.

The effects of recombinant IL-2 on apoptosis of lymphocytes of healthy donors were studied in in vitro experiments. It was shown that the inductive and inhibitory effects of IL-2 on apoptotic process depend on the dose of the cytokine and cell microenvironmental conditions. Culturing of lymphocytes with recombinant IL-2 increases the percent of cells with reduced transmembrane potential, reduces the content of intracellular proteins Bcl-2, Bcl-X(L) and и Bax, and increases the level of Bad. The proapoptotic effect of this cytokine is realized with participation of nuclear transcription factor NF-κB and transcription factor P53.

Such HLA phenotypes as A3B35 and A9B35 occur most frequently in patients with chronic pyelonephritis (CP). In these phenotypes there are most pronounced changes in the lipid phase of red cell membranes and renal tissue. The above changes of blood cell cytomembranes and renal tissue can be used as diagnostic criteria of inflammation activity in pyelonephritis while the HLA antigens are helpful for detection of CP risk groups.