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Archive for a.grevtsev

Dalton Transactions, 2017, 46, 3895-3905

A.I. Solomatina, I.O. Aleksandrova, A.J. Karttunen, S.P. Tunik, I.O. Koshevoy

“Dibenzothiophene-platinated complexes: probing the effect of ancillary ligands on the photophysical performance”

Dalton Transactions, 2017, 46, 3895-3905
DOI: 10.1039/C7DT00349H

source: http://pubs.rsc.org/en/Content/ArticleLanding/2017/DT/C7DT00349H#!divAbstract

Cyclometalation of dibenzothienyl-pyridine (HPyDBT) afforded a series of platinum(II) complexes Pt(PyDBT)(L)Cl (L = DMSO, 1; P(p-C6H4-X)3 (X = H, 2; CF3, 3; OMe, 4; NPh2, 5); 1,3,5-triaza-7-phosphaadamantane, 6; 2,6-dimethylphenyl isocyanide, 7). Chelating bidentate LL ligands formed cationic compounds [Pt(PyDBT)(LL)]+ (LL = 1,2-bis(diphenylphosphino)benzene, 8; 2,2′-bipyridine, 9; 1,10-phenanthroline, 10). Oxidation of a thienyl sulfur atom allowed for the isolation of the sulfone derivative Pt(PyDBT)(PPh3)Cl (11). The title complexes were characterized crystallographically (except 7). Investigation of their photophysical behavior revealed solid state phosphorescence with quantum yields up to 0.45 for neat powders. The ancillary ligands L show a minor influence on the emission energies of the neutral compounds, but affect dramatically the intensity of luminescence. In contrast, the cationic species with diimine ligands demonstrate a significant contribution of the LL fragments into the emissive T1 states that leads to a certain mixing of 3IL and 3LL′CT transitions and causes a substantial bathochromic shift of emission.

Журнал органической химии, 2017, 53(11), 1726-1728

О.М. Нестерова, О.С. Зарубина, В.В. Толстяков, Г.Г. Данагулян, Р.Е. Трифонов, С.Н. Смирнов, П.А. Слепухин, Н.К. Игнатенко, В.А. Островский

“Синтез и строение N-(4,6-диметилпиримидин-2-ил)-2-(5-фенил-2Н-тетразол-2-ил)ацетогидразида и 1-(4,6-диметилпиримидин-2-ил)-3-[(5-фенил-2Н-тетразол-2-ил)метил]-1Н-пиразол-5-ола”

Журнал органической химии, 2017, 53(11), 1726-1728

Синтезированы новые тетразолильные производные 4,6-диметилгидразина, содержащие различные линкерные группы. Определена структура данных соединений методами ЯМР спектроскопии
и рентгеноструктурного анализа

Scientific Reports, 2017, 7, 41991

E. G. Vlakh, E. V. Grachova, D. D. Zhukovsky, A. V. Hubina, A. S. Mikhailova, J. R. Shakirova, V. V. Sharoyko, S. P. Tunik, T. B. Tennikova

“Self-assemble nanoparticles based on polypeptides containing C-terminal luminescent Pt-cysteine complex”

Scientific Reports, 2017, 7, Article number 41991
DOI: 10.1038/srep41991

source: https://www.nature.com/articles/srep41991

The growing attention to the luminescent nanocarriers is strongly stimulated by their potential application as drug delivery systems and by the necessity to monitor their distribution in cells and tissues. In this communication we report on the synthesis of amphiphilic polypeptides bearing C-terminal phosphorescent label together with preparation of nanoparticles using the polypeptides obtained. The approach suggested is based on a unique and highly technological process where the new phosphorescent Pt-cysteine complex serves as initiator of the ring-opening polymerization of α-amino acid N-carboxyanhydrides to obtain the polypeptides bearing intact the platinum chromophore covalently bound to the polymer chain. It was established that the luminescent label retains unchanged its emission characteristics not only in the polypeptides but also in more complicated nanoaggregates such as the polymer derived amphiphilic block-copolymers and self-assembled nanoparticles. The phosphorescent nanoparticles display no cytotoxicity and hemolytic activity in the tested range of concentrations and easily internalize into living cells that makes possible in vivo cell visualization, including prospective application in time resolved imaging and drug delivery monitoring.

Carbohydrate Polymers, 2017, 169, 117–126

N.G. Voron’ko, S.R. Derkach, M.A. Vovk, P.M. Tolstoy

“Complexation of κ-carrageenan with gelatin in the aqueous phase analysed by 1H NMR kinetics and relaxation”

Carbohydrate Polymers, 2017, 169, 117–126
DOI: 10.1016/j.carbpol.2017.04.010

The 1H NMR spectroscopy is used to study the kinetics of gelation in the aqueous mixtures of κ-carrageenan with gelatin. The time dependence of NMR signals intensities shows that the kinetics of gel formation consists of classical ‘fast’ (rate constant k ≈ 6 h−1) and ‘slow’ (k ≈ 1 h−1) periods, corresponding to a coil → helix transition and subsequent aggregation of helices. Upon increase of the κ-carrageenan/gelatin (w/w) ratio Z the rate of the fast process slows down by a factor of 1.6–2.4. Further analysis was done by studying the dependence of spin-spin relaxation times of protons of gelatin on Z in the aqueous phase. A qualitative scheme describing hydrogel formation in the complex solution is given. It is hypothesized that at higher concentration of PECs the hydrogel structure network is stabilized by three types of nodes: triple helices of gelatin and intra-/inter-molecular double helices of κ-carrageenan.

Октябрь

В Октябре выполнено 2347 заявок на сервисные измерения.

Измерено:

  • 2218 спектр 1H
  • 366 спектра 13C
  • 95 спектров DEPT
  • 63 спектров COSY
  • 19 спектра NOESY
  • 52 спектра 31Р
  • 169 спектров 19F

Выполнено 242 заявок на исследовательскую работу.

Green Chemistry, 2017, 19, 3032–3041

G. Werner, K.S. Rodygin, A.A. Kostin, E.G. Gordeev, A.S. Kashin, V.P. Ananikov

“A solid acetylene reagent with enhanced reactivity: fluoride-mediated functionalization of alcohols and phenols”

Green Chemistry, 2017, 19, 3032–3041
DOI: 10.1039/C7GC00724H

source: http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C7GC00724H#!divAbstract

The direct vinylation of an OH group in alcohols and phenols was carried out utilizing a novel CaC2/KF solid acetylene reagent in a simple K2CO3/KOH/DMSO system. The functionalization of a series of hydroxyl-group-containing substrates and the post-modification of biologically active molecules were successfully performed using standard laboratory equipment, providing straightforward access to the corresponding vinyl ethers. The overall process developed involves an atom-economical addition reaction employing only inorganic reagents, which significantly simplifies the reaction set-up and the isolation of products. A mechanistic study revealed a dual role of the F additive, which both mediates the surface etching/renewal of the calcium carbide particles and activates the C[triple bond, length as m-dash]C bond towards the addition reaction. The development of the fluoride-mediated nucleophilic addition of alcohols eliminates the need for strong bases and may substantially extend the areas of application of this attractive synthetic methodology due to increasing functional group tolerance. As a replacement for dangerous and difficult to handle high-pressure acetylene, we propose the solid reagent CaC2/KF, which is easy to handle, does not require dedicated laboratory equipment and demonstrates enhanced reactivity of the acetylenic triple bond. Theoretical calculations have shown that fluoride-mediated activation of the hydroxyl group towards nucleophilic addition significantly reduces the activation barrier and facilitates the reaction.

Science of The Total Environment 2018, 615, 1229–1238

R. Vasilevich, E. Lodygina, V. Beznosikova, E. Abakumov

“Molecular composition of raw peat and humic substances from permafrost peat soils of European Northeast Russia as climate change markers”

Science of The Total Environment 2018, 615 (In Progress, Available online 17 October 2017), 1229–1238
DOI: 10.1016/j.scitotenv.2017.10.053

source: http://www.sciencedirect.com/science/article/pii/S0048969717327560

Humic substances (HSs) from the mire peat soils of the forest-tundra zone of the European northeast part of Russia have been characterized in terms of molecular composition. This was accomplished using solid-state 13C nuclear magnetic resonance (13C NMR) techniques and electron spin resonance (ESR) spectroscopy. The composition depended on the intensity of cryogenic processes in the active layer, the quality of the humification precursors (the degree of peat material transformation), and the biochemical selection of aromatic fragments during humification. Humic acids (HAs) and fulvic acids (FAs) of the peat soils showed the presence of compounds with a low extent of condensation and a low portion of aromatic fragments, which increased with depth. A higher proportion of aliphatic carbon species was found in the HAs, indicating a low degree of organic matter stabilization. Based on the data from the two types of peat soils, we suggest that particular changes in the proportion of aromatic and unoxidized aliphatic fragments on the border of the bottom of the active layer and permafrost layers can be used as markers of current climatic change.

Journal of Molecular Structure, 2017, 1146, 554–561

A. M. Afanasenko, D. V. Boyarskaya, I. A. Boyarskaya, T. G. Chulkova, Y. M. Grigoriev, I. E. Kolesnikov, M. S. Avdontceva, T. L. Panikorovskii, A. I. Panin, A. N. Vereshchagin, M. N. Elinson

“Structures and photophysical properties of 3,4-diaryl-1H-pyrrol-2,5-diimines and 2,3-diarylmaleimides”

Journal of Molecular Structure, 2017, 1146, 554–561
DOI: 10.1016/j.molstruc.2017.06.048

source: http://www.sciencedirect.com/science/article/pii/S0022286017308293

Structural features of 3,4-diaryl-1H-pyrrol-2,5-diimines and their derivatives have been studied by molecular spectroscopy techniques, single-crystal X-ray diffraction, and DFT calculations. According to the theoretical calculations, the diimino tautomeric form of 3,4-diaryl-1H-pyrrol-2,5-diimines is more stable in solution than the imino-enamino form. We also found that the structurally related 2,3-diarylmaleimides exist in the solid state in the dimeric diketo form. 3,4-Diaryl-1H-pyrrol-2,5-diimines and 2,3-diarylmaleimides exhibit fluorescence in the blue region of the visible spectrum. The fluorescence spectra have large Stokes shifts. Aryl substituents at the 3,4-positions of 1H-pyrrol-2,5-diimine do not significantly affect fluorescence properties. The insertion of donor substituents into 2,3-diarylmaleimides leads to bathochromic shift of emission bands with hyperchromic effect.

Визит принцессы Таиланда

источник: http://spbu.ru/press-center/press-relizy/princessa-tailanda-maha-chakri-sirindon-posetila-nauchnyy-park-spbgu

Санкт-Петербургский университет посетила тайская делегация во главе с принцессой Таиланда Махой Чакри Сириндон. Делегация посетила ряд ресурсных центров Научного парка СПбГу. Директор ресурсного центра МРМИ Петр Толстой рассказал об основных направлениях исследований и их реализации в рц МРМИ, об опыте международного сотрудничества с партнерами рц МРМИ.
Подробнее о визите делегации из Таиланда в Научный парк СПбГУ
Репортаж тайского телевидения о посещении Научного парка принцессой Маха Чакри Сириндон

Сентябрь

В сентябре выполнено 1921 заявок на сервисные измерения.

Измерено:

  • 1821 спектр 1H
  • 296 спектра 13C
  • 72 спектров DEPT
  • 22 спектров COSY
  • 22 спектра NOESY
  • 27 спектра 31Р
  • 142 спектров 19F

Выполнено 219 заявок на исследовательскую работу.