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Reactions of electrochemically generated antimony(V) and tin(IV) complex species containing a tridentate O,N,O-donor ligand with various thiols were studied. Among main group metal complexes with N,N-bis(2-hydroxy-di-3,5-tert-butylphenyl)amine (CatH2–NH–CatH2), compounds [Me2Sn(Cat-N-SQ)] (I), [Et2Sn(Cat-N-SQ)] (II), [Ph2Sn(Cat-N-SQ)] (III), [(c-C6H11)2Sb(Cat-N-Cat)] (IV), and [Ph3Sb(Cat-NH-Cat)] (V) are the most active, able to mediate the oxidation of thiols (1-hexanethiol, cyclohexanethiol, and 4-methoxythiophenol), to symmetrical disulfides were identified. The anodic activation of Sb(V) and Sn(IV) complexes involves organic ligands and gives rise to intermediates that react with thiols. During the mediated electrosynthesis, the initial complex species is regenerated in solution. The use of metal complex mediators decreases the anodic overvoltage of the thiol oxidation in comparison with direct electrochemical synthesis. The yields of products depend on complex and thiol structures or ratio. The highest efficiency in the electrocatalytic reactions was found for the [Ph3Sb(Cat-NH-Cat)] complex, which should be used for the synthesis of disulfides.
V. A. Lavrent’Ev; E. V. Shinkar’; I. V. Smolyaninov; Yu. I. Ryabukhin; N. T. Berberova. Antimony(V) and Tin(IV) Complexes with Redox-Active O,N,O-Donor Ligand in the Electrosynthesis of Symmetrical Disulfides. Russian Journal of Coordination Chemistry 2021, 47, 341 -346.
AMA StyleV. A. Lavrent’Ev, E. V. Shinkar’, I. V. Smolyaninov, Yu. I. Ryabukhin, N. T. Berberova. Antimony(V) and Tin(IV) Complexes with Redox-Active O,N,O-Donor Ligand in the Electrosynthesis of Symmetrical Disulfides. Russian Journal of Coordination Chemistry. 2021; 47 (5):341-346.
Chicago/Turabian StyleV. A. Lavrent’Ev; E. V. Shinkar’; I. V. Smolyaninov; Yu. I. Ryabukhin; N. T. Berberova. 2021. "Antimony(V) and Tin(IV) Complexes with Redox-Active O,N,O-Donor Ligand in the Electrosynthesis of Symmetrical Disulfides." Russian Journal of Coordination Chemistry 47, no. 5: 341-346.
The electrochemical oxidation of the chromium(III) and indium(III) complexes with 3,6-di-tert-butyl-o-semiquinolate leading to the formation of active monocationic species is studied by cyclic voltammetry. The reactions of the latter with hydrogen sulfide generate the radical cation of H2S, whose fragmentation affords the proton and thiyl radical. These complexes are proposed for the first time as redox mediators for the one-pot thiolation of inert cycloalkanes C6–C8, which decreases the activation energy of hydrogen sulfide compared to that for direct electrochemical oxidation. The major products of cycloalkane functionalization involving H2S are thiols and organic di- and trisulfides. The yield of the synthesized compounds depends on the type of the mediator: the chromium(III) complex exhibits the highest efficiency in the electrocatalytic transformations.
N. T. Berberova; Elena Shinkar'; I. V. Smolyaninov; A. V. Shvetsova; D. B. Sediki. Chromium(III) and indium(III) 3,6-di-tert-butyl-o-semiquinolate complexes as redox mediators of hydrogen sulfide oxidation in reactions with cycloalkanes. Russian Journal of Coordination Chemistry 2017, 43, 578 -582.
AMA StyleN. T. Berberova, Elena Shinkar', I. V. Smolyaninov, A. V. Shvetsova, D. B. Sediki. Chromium(III) and indium(III) 3,6-di-tert-butyl-o-semiquinolate complexes as redox mediators of hydrogen sulfide oxidation in reactions with cycloalkanes. Russian Journal of Coordination Chemistry. 2017; 43 (9):578-582.
Chicago/Turabian StyleN. T. Berberova; Elena Shinkar'; I. V. Smolyaninov; A. V. Shvetsova; D. B. Sediki. 2017. "Chromium(III) and indium(III) 3,6-di-tert-butyl-o-semiquinolate complexes as redox mediators of hydrogen sulfide oxidation in reactions with cycloalkanes." Russian Journal of Coordination Chemistry 43, no. 9: 578-582.
A new mixed-ligand tin(IV) complex 2 derived from 3,6-di-tert-butyl-o-benzoquinone and ferrocenylaldimine phenol 1 has been prepared and characterized by different physicochemical methods (IR, 1HNMR, and 119Sn NMR spectroscopies). Electrochemical transformations of complex 2 have been studied by cyclic voltammetry. Catecholate and ferrocenyl groups have been found to take part in the redox transformations. Chemical oxidation of complex 2 with silver triflate in a dichloromethane solution has been studied. Formation of monocationic complex 2+ has been detected by EPR spectroscopy. The catecholate ligand has been found to be the primary redox center subjected to oxidation.
S. V. Baryshnikova; E. V. Bellan; A. I. Poddel’Skii; I. V. Smolyaninov; N. T. Berberova; G. A. Abakumov. Synthesis, structure, and properties of a new multiredox-active Sn(IV) complex based on 3,6-di-tert-butyl-o-benzoquinone and ferrocenylaldimine phenol. Doklady Chemistry 2017, 474, 101 -104.
AMA StyleS. V. Baryshnikova, E. V. Bellan, A. I. Poddel’Skii, I. V. Smolyaninov, N. T. Berberova, G. A. Abakumov. Synthesis, structure, and properties of a new multiredox-active Sn(IV) complex based on 3,6-di-tert-butyl-o-benzoquinone and ferrocenylaldimine phenol. Doklady Chemistry. 2017; 474 (1):101-104.
Chicago/Turabian StyleS. V. Baryshnikova; E. V. Bellan; A. I. Poddel’Skii; I. V. Smolyaninov; N. T. Berberova; G. A. Abakumov. 2017. "Synthesis, structure, and properties of a new multiredox-active Sn(IV) complex based on 3,6-di-tert-butyl-o-benzoquinone and ferrocenylaldimine phenol." Doklady Chemistry 474, no. 1: 101-104.
N. T. Berberova; Elena Shinkar'; Ivan Smolyaninov; K. P. Pashchenko. Redox mediators of hydrogen sulfide oxidation in reactions with cycloalkanes. Doklady Chemistry 2015, 465, 295 -298.
AMA StyleN. T. Berberova, Elena Shinkar', Ivan Smolyaninov, K. P. Pashchenko. Redox mediators of hydrogen sulfide oxidation in reactions with cycloalkanes. Doklady Chemistry. 2015; 465 (2):295-298.
Chicago/Turabian StyleN. T. Berberova; Elena Shinkar'; Ivan Smolyaninov; K. P. Pashchenko. 2015. "Redox mediators of hydrogen sulfide oxidation in reactions with cycloalkanes." Doklady Chemistry 465, no. 2: 295-298.
Elena Shinkar'; A. V. Shvetsova; D. B. Sediki; N. T. Berberova. Redox activation of hydrogen sulfide in reaction with cycloheptane. Russian Journal of Electrochemistry 2015, 51, 1046 -1053.
AMA StyleElena Shinkar', A. V. Shvetsova, D. B. Sediki, N. T. Berberova. Redox activation of hydrogen sulfide in reaction with cycloheptane. Russian Journal of Electrochemistry. 2015; 51 (11):1046-1053.
Chicago/Turabian StyleElena Shinkar'; A. V. Shvetsova; D. B. Sediki; N. T. Berberova. 2015. "Redox activation of hydrogen sulfide in reaction with cycloheptane." Russian Journal of Electrochemistry 51, no. 11: 1046-1053.
N. T. Berberova; Elena Shinkar'; Ivan Smolyaninov; V. F. Abdulaeva. Anodic activation of hydrogen sulfide in reaction with cyclopentane. Russian Journal of General Chemistry 2015, 85, 998 -1000.
AMA StyleN. T. Berberova, Elena Shinkar', Ivan Smolyaninov, V. F. Abdulaeva. Anodic activation of hydrogen sulfide in reaction with cyclopentane. Russian Journal of General Chemistry. 2015; 85 (4):998-1000.
Chicago/Turabian StyleN. T. Berberova; Elena Shinkar'; Ivan Smolyaninov; V. F. Abdulaeva. 2015. "Anodic activation of hydrogen sulfide in reaction with cyclopentane." Russian Journal of General Chemistry 85, no. 4: 998-1000.
A cryoprotective effect of an addition of a new synthetic antioxidant – a representative of phosphorus-containing sterically hindered phenols is presented. The efficiency of the compound was shown to exceed the effect of lipid-soluble antioxidants butylated hydroxytoluene (BHT) and trolox in the conditions of cryopreservation of beluga sperm in the presence of the modified Stein’s medium. It was shown that the level of carbonyl oxidation by-products, which can react with thiobarbituric acid (TBARS), in beluga sperm was inversely proportional to the motility time of sperm cells. The fertility of beluga sperm increased 2 times upon the addition of phosphorus-containing phenol to a modified Stein’s medium. The prospects of the new antioxidant application to improve cryoresistance of beluga sperm in the conditions of cryopreservation for its efficient protection from the peroxidation processes are discussed.
V.P. Osipova; M.N. Kolyada; N.T. Berberova; E.R. Milaeva; E.N. Ponomareva; M.M. Belaya. Cryoprotective effect of phosphorous-containing phenolic anti-oxidant for the cryopreservation of beluga sperm. Cryobiology 2014, 69, 467 -472.
AMA StyleV.P. Osipova, M.N. Kolyada, N.T. Berberova, E.R. Milaeva, E.N. Ponomareva, M.M. Belaya. Cryoprotective effect of phosphorous-containing phenolic anti-oxidant for the cryopreservation of beluga sperm. Cryobiology. 2014; 69 (3):467-472.
Chicago/Turabian StyleV.P. Osipova; M.N. Kolyada; N.T. Berberova; E.R. Milaeva; E.N. Ponomareva; M.M. Belaya. 2014. "Cryoprotective effect of phosphorous-containing phenolic anti-oxidant for the cryopreservation of beluga sperm." Cryobiology 69, no. 3: 467-472.
The antiradical activity and in vitro cytotoxicity of novel organotin complexes with 2,6-di-tert-butylphenol pendant were established.
D. B. Shpakovsky; Christina Banti; E. M. Mukhatova; Yu. A. Gracheva; V. P. Osipova; N. T. Berberova; D. V. Albov; T. A. Antonenko; Leonid Aslanov; E. R. Milaeva; Sotiris Hadjikakou. Synthesis, antiradical activity and in vitro cytotoxicity of novel organotin complexes based on 2,6-di-tert-butyl-4-mercaptophenol. Dalton Transactions 2014, 43, 6880 -6890.
AMA StyleD. B. Shpakovsky, Christina Banti, E. M. Mukhatova, Yu. A. Gracheva, V. P. Osipova, N. T. Berberova, D. V. Albov, T. A. Antonenko, Leonid Aslanov, E. R. Milaeva, Sotiris Hadjikakou. Synthesis, antiradical activity and in vitro cytotoxicity of novel organotin complexes based on 2,6-di-tert-butyl-4-mercaptophenol. Dalton Transactions. 2014; 43 (18):6880-6890.
Chicago/Turabian StyleD. B. Shpakovsky; Christina Banti; E. M. Mukhatova; Yu. A. Gracheva; V. P. Osipova; N. T. Berberova; D. V. Albov; T. A. Antonenko; Leonid Aslanov; E. R. Milaeva; Sotiris Hadjikakou. 2014. "Synthesis, antiradical activity and in vitro cytotoxicity of novel organotin complexes based on 2,6-di-tert-butyl-4-mercaptophenol." Dalton Transactions 43, no. 18: 6880-6890.
Initiation of the reaction between hydrogen sulfide and aliphatic, aromatic, and heteroaromatic hydrocarbons in acetonitrile using the binary system organic base-anode is described. The reaction of hydrogen sulfide with nitrogen-containing organic bases is studied by means of cyclic voltammetry. The reaction of hydrogen sulfide with triethylamine leads to the formation of thiolate anion. The next step o reaction is electrochemical oxidation of the thiolate anion that to lead thiyl radical formation thiyl radicals. In the presence of binary system on the basis of hydrogen sulfide aliphatic, aromatic, and heteroaromatic thiols and sulfides are formed at room temperature.
Elena Shinkar'; I. V. Smolyaninov; A. O. Okhlobystin; N. T. Berberova. Binary system organic base-anode in the oxidative activation of hydrogen sulfide. Russian Journal of General Chemistry 2012, 82, 815 -818.
AMA StyleElena Shinkar', I. V. Smolyaninov, A. O. Okhlobystin, N. T. Berberova. Binary system organic base-anode in the oxidative activation of hydrogen sulfide. Russian Journal of General Chemistry. 2012; 82 (5):815-818.
Chicago/Turabian StyleElena Shinkar'; I. V. Smolyaninov; A. O. Okhlobystin; N. T. Berberova. 2012. "Binary system organic base-anode in the oxidative activation of hydrogen sulfide." Russian Journal of General Chemistry 82, no. 5: 815-818.
In this work, the routes of the redox reactions of chalcogenbiscyclanones and the products of their S-, O-, N-heterocyclization in organic solvents were analyzed and validated. The influence of the nature of the heteroatoms and substituents on the redox activity of S- and Se-containing biscyclanones, benzannelated thianthrenes, oxathianthrenes, and diazepine was established based on electrochemical studies, ESR spectroscopy data, and the results of quantum chemical calculations
Elena Shinkar'; O. V. Fedotova; K. P. Pashchenko; Ya. B. Aref’Ev; N. T. Berberova. Electrochemical reactions of chalcogenbiscyclanones and the products of their S-, O-, and N-heterocyclization. Russian Journal of Electrochemistry 2011, 47, 1172 -1179.
AMA StyleElena Shinkar', O. V. Fedotova, K. P. Pashchenko, Ya. B. Aref’Ev, N. T. Berberova. Electrochemical reactions of chalcogenbiscyclanones and the products of their S-, O-, and N-heterocyclization. Russian Journal of Electrochemistry. 2011; 47 (10):1172-1179.
Chicago/Turabian StyleElena Shinkar'; O. V. Fedotova; K. P. Pashchenko; Ya. B. Aref’Ev; N. T. Berberova. 2011. "Electrochemical reactions of chalcogenbiscyclanones and the products of their S-, O-, and N-heterocyclization." Russian Journal of Electrochemistry 47, no. 10: 1172-1179.
The radical scavenging effect of the substituted catecholates (1–3, 6) and o-amidophenolates (4, 5) of triphenylantimony(V) in reactions with DPPH• radical and in a process of oleic acid peroxidation was studied in details. Complexes 1–6 show the high activity in radical scavenging reactions with DPPH• radical leading to disappearance of radical species. Complexes were demonstrated to be high-efficient inhibitors of chain-radical process of the peroxidation of oleic acid as well as the effective destructors of the formed hydroperoxides. It was found that the effectiveness of complexes studied in the inhibition of the peroxidation of oleic acid depends on the first oxidation potential of complex.
Ivan V. Smolyaninov; Natalia A. Antonova; Andrey I. Poddel’Sky; Susanna A. Smolyaninova; Viktoria P. Osipova; Nadezhda T. Berberova. Radical scavenging activity of sterically hindered catecholate and o-amidophenolate complexes of LSbVPh3 type. Journal of Organometallic Chemistry 2011, 696, 2611 -2620.
AMA StyleIvan V. Smolyaninov, Natalia A. Antonova, Andrey I. Poddel’Sky, Susanna A. Smolyaninova, Viktoria P. Osipova, Nadezhda T. Berberova. Radical scavenging activity of sterically hindered catecholate and o-amidophenolate complexes of LSbVPh3 type. Journal of Organometallic Chemistry. 2011; 696 (13):2611-2620.
Chicago/Turabian StyleIvan V. Smolyaninov; Natalia A. Antonova; Andrey I. Poddel’Sky; Susanna A. Smolyaninova; Viktoria P. Osipova; Nadezhda T. Berberova. 2011. "Radical scavenging activity of sterically hindered catecholate and o-amidophenolate complexes of LSbVPh3 type." Journal of Organometallic Chemistry 696, no. 13: 2611-2620.
The reactions of hydrogen sulfide with transition metal complexes containing redox-active ligands are studied. A combination of electrochemical and spectral data indicates that the one-electron process affording the hydrogen sulfide radical and monoanionic complexes is an elementary act for the most part of the reactions studied. The accessibility of the metal center in the Co, Ni, Zn, and Pt complexes allows hydrogen sulfide to preliminary coordinate to the metal followed by the inner-sphere electron transfer in the hydrogen sulfide-metal-organic ligand system. Active intermediates (radical cation, thiyl radical, and proton) formed due to oxidation react with aromatic substrates. The substitution reaction in the aromatic ring produces a mixture of isomeric thiols and dimerization products of organylthiyl radicals (disulfides).
I. V. Smolyaninov; A. O. Okhlobystin; A. I. Poddel’Sky; N. T. Berberova; I. L. Eremenko. Transition metal complexes with “non-innocent” ligands in the activation of hydrogen sulfide. Russian Journal of Coordination Chemistry 2011, 37, 12 -25.
AMA StyleI. V. Smolyaninov, A. O. Okhlobystin, A. I. Poddel’Sky, N. T. Berberova, I. L. Eremenko. Transition metal complexes with “non-innocent” ligands in the activation of hydrogen sulfide. Russian Journal of Coordination Chemistry. 2011; 37 (1):12-25.
Chicago/Turabian StyleI. V. Smolyaninov; A. O. Okhlobystin; A. I. Poddel’Sky; N. T. Berberova; I. L. Eremenko. 2011. "Transition metal complexes with “non-innocent” ligands in the activation of hydrogen sulfide." Russian Journal of Coordination Chemistry 37, no. 1: 12-25.
E. M. Mukhatova; N. T. Limonova; M. N. Kolyada; V. P. Osipova; N. T. Berberova; Yu. T. Pimenov; E. R. Milaeva. Protecting Effect of the Free Base Porphyrins on the Rate of Hydrogen Peroxide Decomposition by Hemolysate of Human Blood Erythrocytes in the Presence of Mercury and Tin Compounds. Macroheterocycles 2011, 4, 216 -221.
AMA StyleE. M. Mukhatova, N. T. Limonova, M. N. Kolyada, V. P. Osipova, N. T. Berberova, Yu. T. Pimenov, E. R. Milaeva. Protecting Effect of the Free Base Porphyrins on the Rate of Hydrogen Peroxide Decomposition by Hemolysate of Human Blood Erythrocytes in the Presence of Mercury and Tin Compounds. Macroheterocycles. 2011; 4 (3):216-221.
Chicago/Turabian StyleE. M. Mukhatova; N. T. Limonova; M. N. Kolyada; V. P. Osipova; N. T. Berberova; Yu. T. Pimenov; E. R. Milaeva. 2011. "Protecting Effect of the Free Base Porphyrins on the Rate of Hydrogen Peroxide Decomposition by Hemolysate of Human Blood Erythrocytes in the Presence of Mercury and Tin Compounds." Macroheterocycles 4, no. 3: 216-221.
The mechanisms of redox transformations of sterically hindered [1IBQ]-[3IBQ], 9,10-iminophenanthraquinone [4IFQ], and o-aminophenol [5AP] have been studied by cyclic voltammetry. It has been shown that the reduction process in tetrahydrofuran consists of two consecutive reversible steps leading to the formation of a radical anion and a dianion. In the case of acetonitrile, only the first redox process is detected, which involves the steps of protonation and electron addition resulting in the formation of a monoanion. Quantum-chemical calculations indicate a lower degree of participation of the six-membered nonaromatic carbon ring in the spin density delocalization in the o-iminosemiquinonate radical anions as compared to o-benzosemiquinonate radical anions. The oxidation of iminoquinones results in the formation of an unstable radical cation, which undergoes further chemical transformations. An increase in the acidity of a medium leads to the formation of protonated forms with the reduction potential being shifted anodically. The introduction of screening groups makes it possible to suppress side reactions of hydrolysis and cyclization of oxidized o-aminophenol [5AP] forms. Therefore, the major product of complete electrolysis is o-iminobenzoquinone [2IBQ].
I. V. Smolyaninov; N. N. Letichevskaya; A. V. Kulakov; Ya. B. Aref’Ev; K. P. Pashchenko; N. T. Berberova. Study of the mechanism of redox transformations of sterically hindered N-aryl-o-iminoquinones. Russian Journal of Electrochemistry 2007, 43, 1187 -1199.
AMA StyleI. V. Smolyaninov, N. N. Letichevskaya, A. V. Kulakov, Ya. B. Aref’Ev, K. P. Pashchenko, N. T. Berberova. Study of the mechanism of redox transformations of sterically hindered N-aryl-o-iminoquinones. Russian Journal of Electrochemistry. 2007; 43 (10):1187-1199.
Chicago/Turabian StyleI. V. Smolyaninov; N. N. Letichevskaya; A. V. Kulakov; Ya. B. Aref’Ev; K. P. Pashchenko; N. T. Berberova. 2007. "Study of the mechanism of redox transformations of sterically hindered N-aryl-o-iminoquinones." Russian Journal of Electrochemistry 43, no. 10: 1187-1199.
The reaction of 2-hydroxy-6-methylpyridine (HL, 1) with nonanuclear nickel trimethyl-acetate Ni9(OH)6(OOCCMe3)12(HOOCCMe3)4 (2) in MeCN with a ratio M: L = 1: 1 under mild conditions (20 °C, 15 min) led to degradation of the metal core to form the hexanuclear complex (HL)2(µ 2-HL)2Ni6(µ3-OH)2(µ2-H2O)2(µ-OOCCMe3)8(η-OOCCMe3)2 (3). Further heating of 3 in acetonitrile at 80 °C for 4 h afforded the (HL)Ni6(µ 3-OH)(µ3,η2-L)3(µ,η2-L)(µ3-L)(µ 3-OOCCMe3)(µ-OOCCMe3)4(η2-OOCCMe3) complex. The reaction with the use of a 2: 1 THF-EtOH mixture instead of acetonitrile at 50 °C gave the decanuclear complex [Ni10(µ 3-O)2(µ3-OH)4(µ-OOCCMe3)6(µ3,η 2-L)6(EtOH)6](H2O)2, which is also produced from compounds 1 and 2 in ethanol. The structures of the resulting complexes were established by X-ray diffraction.
M. E. Nikiforova; A. A. Sidorov; G. G. Aleksandrov; V. N. Ikorskii; I. V. Smolyaninov; A. O. Okhlobystin; N. T. Berberova; I. L. Eremenko. Replacement of carboxylate bridges in polynuclear nickel pivalates with 2-hydroxy-6-methylpyridine anions. Bulletin of the Academy of Sciences of the USSR Division of Chemical Science 2007, 56, 943 -952.
AMA StyleM. E. Nikiforova, A. A. Sidorov, G. G. Aleksandrov, V. N. Ikorskii, I. V. Smolyaninov, A. O. Okhlobystin, N. T. Berberova, I. L. Eremenko. Replacement of carboxylate bridges in polynuclear nickel pivalates with 2-hydroxy-6-methylpyridine anions. Bulletin of the Academy of Sciences of the USSR Division of Chemical Science. 2007; 56 (5):943-952.
Chicago/Turabian StyleM. E. Nikiforova; A. A. Sidorov; G. G. Aleksandrov; V. N. Ikorskii; I. V. Smolyaninov; A. O. Okhlobystin; N. T. Berberova; I. L. Eremenko. 2007. "Replacement of carboxylate bridges in polynuclear nickel pivalates with 2-hydroxy-6-methylpyridine anions." Bulletin of the Academy of Sciences of the USSR Division of Chemical Science 56, no. 5: 943-952.
Yu.T. Pimenov; N.T. Berberova; V.P. Osipova; M.N. Kolyada; E.R. Milaeva. TOXIC ACTION OF MERCURY AND TIN COMPOUNDS ON YOUNGER STURGEON FISH. Vestnik Yuzhnogo nauchnogo tsentra 2005, 1, 1 .
AMA StyleYu.T. Pimenov, N.T. Berberova, V.P. Osipova, M.N. Kolyada, E.R. Milaeva. TOXIC ACTION OF MERCURY AND TIN COMPOUNDS ON YOUNGER STURGEON FISH. Vestnik Yuzhnogo nauchnogo tsentra. 2005; 1 (1):1.
Chicago/Turabian StyleYu.T. Pimenov; N.T. Berberova; V.P. Osipova; M.N. Kolyada; E.R. Milaeva. 2005. "TOXIC ACTION OF MERCURY AND TIN COMPOUNDS ON YOUNGER STURGEON FISH." Vestnik Yuzhnogo nauchnogo tsentra 1, no. 1: 1.