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A new yttrium(iii) complex with the pincer type bis(phosphinophenyl)amide ligand was synthesized and its activity and selectivity in the isoprene polymerization reaction was studied. An ultrahigh molecular weight polyisoprene with a > 99% content of 1,4-cis units was obtained.

New unsymmetrically substituted benzothiadiazoles were synthesized from 4,7-dibromo-2,1,3-benzothiadiazole via the sequence of Pd-catalyzed Suzuki and Buchwald–Hartwig cross-coupling reactions with 4-methoxyphenylboronic acid and heterocyclic amines, respectively. Based on initially performed photophysical study as well as DFT calculation, these compounds, in particular with dibenzoazepine core, can be selected as promising scaffolds for further fine-tuning of their properties to be used in optoelectronics including OLED technologies.

A procedure for the phosphorylation of the tripeptide Tyr-Thr-Lys with isopropyl methyl- or (deuteromethyl)phosphonochloridate is developed. The phosphorylated tripeptides are intended for use as reference standards in the analysis of blood samples of people suspected to have been exposed to acetylcholinesterase inhibitors. Conditions of hromatographic separation and purification of the synthesized compounds are determined and optimized, which ensures the preparation of high-purity phosphorylated tripeptides.

The activity of known and newly synthesized Ru-carbene catalysts in the metathesis polymerization of 1,5-cyclooctadiene and interchain cross-metathesis of synthesized polybutadiene with polynorbornenes is studied. First- and second-generation Grubbs Ru-complexes, second-generation Hoveyda–Grubbs complexes, and their modified analogs with asymmetric fluoro-containing ligands and unsaturated imidazolyl moieties are used as catalysts. It is shown that in the presence of the second-generation modified and nonmodified catalysts a partially crystalline polybutadiene is formed, in which blocks with trans-С=С bonds are about four times longer than blocks containing cis-С=С bonds. In the case of catalysts with bulkier ligands, the length of trans blocks is smaller and the melting temperature of the polymer is lower. The activities of the catalysts are compared by in situ 1Н NMR monitoring. New norbornene-butadiene multiblock copolymers are prepared for the first time by cross-metathesis between polybutadiene and polynorbornene. The highest degree of blockiness of the copolymers is attained when using second-generation Grubbs and Hoveyda–Grubbs catalysts. The activity sequences for the studied catalysts are constructed. It is shown that macromolecular cross-metathesis occurs more intensively in the presence of the catalysts with less bulky ligands.

Currently, the chemistry of organofluorine compounds is a leading and rapidly developing area of organic chemistry. Fluorine present in a molecule largely determines its specific chemical and biological properties. This thematic issue covers the trends of organofluorine chemistry that have been actively developed in Russia the last 15 – 20 years. The review describes nucleophilic substitution and heterocyclization reactions involving fluorinated arenes and quinones and skeletal cationoid rearrangements in the polyfluoroarene series. The transformations involving CF3-substituted carbocations and radical cations are considered. Heterocyclization and oxidative addition reactions of trifluoroacetamide derivatives and transformations of the organic moiety in polyfluorinated organoboranes and borates with retention of the carbon – boron bond are discussed. Particular attention is devoted to catalytic olefination using freons as an efficient synthetic route to fluorinated compounds. The application of unsymmetrical fluorine-containing N-heterocyclic carbene ligands as catalysts for olefin metathesis is demonstrated. A variety of classes of organofluorine compounds are considered, in particular, polyfluorinated arenes and 1,2-diaminobenzenes, 1-halo-2-trifluoroacetylacetylenes, α-fluoronitro compounds, fluorinated heterocycles, 2-hydrazinylidene-1,3-dicarbonyl derivatives, imines and silanes. The potential practical applications of organofluorine compounds in fundamental organic chemistry, materials science and biomedicine are outlined. The bibliography includes 1019 references.

The review summarizes literature data on the methods for the introduction of fluorine atoms and fluoralkyl groups into different ligands to construct metathesis-active ruthenium carbene complexes. It also analyzes the influence of fluorinated ligands on the catalytic activity of the complexes. The choice, structure and positions of fluorinated substituents in NHC ligands are generally dictated by the desire to increase the electrophilicity of the ruthenium atom due to the electron-withdrawing effect of fluorine atoms and fluoroalkyl groups, resulting, as a rule, in an increase in the activity of the ruthenium complex. In catalysts with unsymmetrical fluorine-containing NHC ligands, there is a possibility of additional Ru–F coordination, making the complexes much more stable and, consequently, more active. The presence of fluorine in chelating alkylidene ligands provides an increase in the catalyst initiation rate due to a weakening of the ruthenium – heteroatom bond. Besides, the introduction of polyfluoroalkyl groups into ligands solves the problem of catalyst recovery using fluorous biphasic systems for reuse. The bibliography includes 172 references.

New CF3-containing derivatives of (5-aminoindol-3-yl)acetic acid were synthesized from 5-nitroindole and trifluoropyruvate or 2-diazotrifluoropropionate. Their reactions with isocyanates allowed us to obtain the series of new ureas, including sulfonylureas, containing a pharmacophore moiety of α-(trifluoromethyl)indolylacetic acid.

New monothiolate ruthenium alkylidene complexes bearing bulky tricyclic N-heterocyclic carbene ligands decorated with two geminal trifluoromethyl groups were synthesized. Their catalytic activity in representative olefin metathesis reactions, such as ring closing metathesis of diallyltosylamine and selfmetathesis of allylbenzene, has been evaluated.

Gold polyacrylate (aurumacryl) belonging to a new class of compounds for oncology — metal polyacrylates — was shown to exhibit strong antitumor activity. Aurumacryl causes 80—90% growth inhibition in vivo of murine solid tumors (Lewis lung carcinoma, Ca-755 adenocarcinoma, and Acatol adenocarcinoma) compared to the control and induces cell death in vitro in 60% of MCF-7 human breast carcinoma cells. Substantial changes in proliferation kinetics of the surviving fraction of tumor cells following treatment with aurumacryl were observed, which are related to the predominant accumulation (93%) of cells in the proliferative resting phase G0 and a substantial decrease in the percentage of proliferating cells (7%). These data provide evidence that the cells that survive lose reproductive ability under treatment with aurumacryl.

We synthesized an ultra low bandgap terpolymer denoted as P containing fluorinated-fluorene attached thiadiazoloquinoxaline and benzothiadiazole acceptors and thiophene as donor in its backbone and investigated its optical and electrochemical properties. This terpolymer is used for as donor along with PC 71 BM as electron acceptor in solution processed polymer solar cells (PSCs). The P showed a shows strong absorption band from 650 nm to 1100 nm with an optical bandgap of 1.12 eV and highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of −5.25 eV and −3.87 eV, respectively. After the optimization of P to PC 71 BM weight ratio, the optimized weight ratio 1:2 in chlorobenzene (CB) solution, the PSC showed overall power conversion efficiency of 4.10% (J sc of 10.96 mA/cm 2 , V oc of 0.68 V and FF of 0.55). After the solvent additive (3 v% DIO) followed by subsequent thermal annealing (SA-TA) the PCE has been increased up to 7.54% with J sc of 16.12 mA/cm 2 , V oc of 0.65 V and FF of 0.72. The increase in the PCE is related with the enhancement in the both J sc and FF, attributed optimized nanoscale morphology of the active layer for both efficient exciton dissociation and charge transport towards the electrodes and balanced charge transport in the device, induced by the TSA treatment of the active layer. This is the highest PCE of PSCs with an energy loss about 0.47 eV with the low bandgap of 1.12 eV.

An efficient and scaled-up synthesis of the imidazol-2-ylidene-based unsymmetrical NHC precursors bearing the sterically demanding hexafluoroisopropylalkoxy group [(CF3 )2 (OR)C-] at the ortho position of the N-aryl substituent was developed. The key step of the method involved the transformation of a Mes-substituted oxazolinium tetrafluoroborate salt through the reaction with the corresponding binucleophilic fluoroalkyl-substituted aniline. The subsequent post-modification of the resulting hydroxyl-containing salt through a simple one-step O-alkylation protocol provided access to a new family of unsymmetrical fluorinated NHC precursors. These compounds were successfully utilized for the preparation of several novel metal complexes. The molecular structures of some NHC precursors and their metal complexes have been unambiguously characterized by single-crystal X-ray diffraction analysis. A preliminary evaluation of the catalytic activity of the palladium complexes was performed on a Buchwald-Hartwig amination reaction. As a result, two PEPPSI-type (PEPPSI=pyridine-enhanced pre-catalyst preparation stabilization and initiation) Pd complexes have demonstrated promising activity in alkane solvents.

Novel heteroleptic cyclometallated 1,2,3-triazol-5-ylidene IrIII complexes with 2-(5-trifluoromethyl-2H-1,2,4-triazol-3-yl)pyridine or 2-(1H-tetrazol-5-yl)pyridine as the ancillary ligands demonstrate photoluminescence in green (520 nm) and blue (450–480 nm) regions.

Pentapeptide analogs of somatostatin containing an (R)-1,3-thiazolidine fragment (Thz) of the general formula X—Thz—Phe—D-Trp—Lys(Y)—Thr—Z were synthesized for the first time. The synthesized compounds were tested for cytotoxic activity against three cancer cell lines (MCF-7, PC3, and HCT-116) and against human embryo fibroblasts.

New olefin metathesis catalysts, unsaturated analogues of the Grubbs II and Hoveyda–Grubbs II ones, bearing bulky (alkoxy)hexafluoroisopropyl groups in one of the aryl substituent of NHC ligand provide high conversions in model ring closing metathesis of diallyl- and allylmethallylmalonates.

The carbonyl cobalt complex Cp*Co(CO)I2 catalyzes carbenoid Co alkylation of N-(pyrimidin-2-yl)indole with methyl 3,3,3-trifluoro-2-diazopropionate regioselectively giving 2-substituted indole, while the N,N’-ligated cations [CpCo(L)I]+ (L = bipy, phen) provide 3-substitution exclusively. The structure of [CpCo(phen)I]PF6 was investigated by X-ray diffraction.

New Boc-protected pentapeptide amides of the general formula Boc—Cys(Boc)—Phe—d-Trp—Lys(Boc)—Thr—NHR, which are analogs of the natural hormone somatostatin, were synthesized. The cytotoxic activity of the new compounds was evaluated against the cancer cell lines MCF-7, PC 3, and HCT-116 by the MTT test, and some of these compounds were found to exhibit activity at micromolar concentrations.

The efficient method for the synthesis of novel trifluoromethyl-containing hydroxy- and aminostyrenes has been developed. The reaction sequence includes the selective insertion of CF3-substituted carbene, which was catalytically derived from methyl 3,3,3-trifluoro-2-diazopropionate, into the OH- or NH-bonds of easily available o-bromophenol and o-bromoaniline derivatives followed by a bromine substitution for vinyl group via Pd-catalyzed Stille reaction.

Reactions of 2-haloethyl- or 3-halopropylamine salts with NH-substrates (indoline, 1,2,3,4-tetrahydroquinoline, aniline, and N-ethylaniline) in the presence of NaHCO3 in water furnished various N-aminoalkyl derivatives of heterocyclic and aromatic amines.

Two novel quinoxalinothiadiazole-containing dibromides—4,9-dibromo-6,7-bis(9,9-didodecyl7-fluoro-9H-fluoren-2-yl)[1,2,5]thiadiazolo[3,4-g]quinoxaline (11) and 4,9-dibromo-6,7-bis(9,9-didodecyl-5,7-difluoro-9H-fluoren-2-yl)[1,2,5]thiadiazolo[3,4-g]quinoxaline (19)—have been synthesized, which are promising strong electron-accepting building blocks for preparing highly efficient narrow-bandgap D–A conjugated polymers. The composition and structure of monomers 11 and 19 have been proved by elemental analysis data, IR spectroscopy, and 1H and 13C NMR.

A simple and convenient one-step method for the preparation of symmetrical α-diketones has been proposed. The latter are intended to be used in synthesis of new carbazole- and fluorene-containing quinoxalines showing electroluminescent and photovoltaic properties.

Metal-catalyzed CH-functionalization of pyrrole and its derivatives via insertion of CF3-carbene generated from methyl 2-diazo-3,3,3-trifluoropropionate was studied. The reactions are completed within few minutes upon heating in toluene in the presence of 1 mol.% of commercially available copper trifluoroacetylacetonate. These reaction conditions allow simultaneous introduction of trifluoromethyl and methyl carboxylate groups into the aromatic pyrrole ring. Conditions for C(2)-selective monofunctionalization of NH-pyrroles were developed.

The structure and properties of dispersions of pristine and covalently modified multiwalled carbon nanotubes (MWCNTs) in N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), N,N-dimethylformamide (DMF) and water have been studied. It has been shown that the dispersions in NMP have the highest stability and smallest particle size. The study of MWCNT dispersions in DMAc with various dispersing polymers, such as polyvinylpyrrolidone (PVP), polyethylene glycol, block copolymers of polyethylene glycol and polypropylene glycol of various molecular weights, ethylenediamine tetrakis(ethoxylate-block-propoxylate) tetrol, and ethylenediamine tetrakis(propoxylate-block-ethoxylate) tetrol has revealed that PVP has the best dispersing capacity. It has been found that the particle size and the yield of MWCNTs dispersed in DMAc depend on the nature and molecular weight of the dispersing polymer, as well as on the solvent quality. Polysulfone hollow fiber ultrafiltration membranes with PVP-modified MWCNT additives (PVP is one of the components of the spinning solutions) have been prepared by the phase inversion method. It has been found that the addition of 0.00084-0.0048% MWCNT in a spinning solution makes it possible to vary the transport properties of the hollow fiber membranes in a wide range.

Importance and advantages of membrane methods for concentrating a bovine pepsin extract are substantiated. A method for the filtration and concentration of this extract with the use of a test bench is considered, and a sixfold increase in enzyme activity is reached.

New olefin metathesis catalysts, analogues of Grubbs II ones, bearing hexafluoroisopropylmethoxy groups in NHC ligand, provide high conversions in model ring closing metathesis of diallylmalonate and cross metathesis of allylbenzene with 1,3-diacetoxybut-2-ene.

International audience; Novel ruthenium carbene complexes bearing unsymmetrical NHC-ligands based on N-alkyl-NA '-arylimidazoline with hexafluoroisopropylmethoxy group in para-position of N-aryl moiety have been synthesized. Catalytic activity of complexes obtained was investigated on model reactions of intra- and intermolecular olefin metathesis.

The challenges of the modern society and the growing demand of high-technology sectors of industrial production bring about a new phase in the development of organic synthesis. A cutting edge of modern synthetic methods is introduction of functional groups and more complex structural units into organic molecules with unprecedented control over the course of chemical transformation. Analysis of the state-of-the-art achievements in selective organic synthesis indicates the appearance of a new trend — the synthesis of organic molecules, biologically active compounds, pharmaceutical substances and smart materials with absolute selectivity. Most advanced approaches to organic synthesis anticipated in the near future can be defined as 'atomic precision' in chemical reactions. The present review considers selective methods of organic synthesis suitable for transformation of complex functionalized molecules under mild conditions. Selected key trends in the modern organic synthesis are considered including the preparation of organofluorine compounds, catalytic cross-coupling and oxidative cross-coupling reactions, atom-economic addition reactions, methathesis processes, oxidation and reduction reactions, synthesis of heterocyclic compounds, design of new homogeneous and heterogeneous catalytic systems, application of photocatalysis, scaling up synthetic procedures to industrial level and development of new approaches to investigation of mechanisms of catalytic reactions. The bibliography includes 840 references.

Palladium-containing carboxylated carbon nanofibers were studied as catalysts for hydrogenation of double bond >C=C< in olefins, unsaturated alcohols, and acids, as well as for hydrogenation of nitroarenes. The developed catalyst is 7 times more efficient than the industrial analog (Pd/C).

CF3-Containing α-arylpropargyl-α-amino carboxylates and α-arylpropargyl-α-amino phosphonates on treatment with the Bronsted or Lewis acids undergo cyclization involving the free NH2 group and triple bond to yield the corresponding dehydroprolines and their phosphorus analogs.

Signalling pathway activation analysis is a powerful approach for extracting biologically relevant features from large-scale transcriptomic and proteomic data. However, modern pathway-based methods often fail to provide stable pathway signatures of a specific phenotype or reliable disease biomarkers. In the present study, we introduce the in silico Pathway Activation Network Decomposition Analysis (iPANDA) as a scalable robust method for biomarker identification using gene expression data. The iPANDA method combines precalculated gene coexpression data with gene importance factors based on the degree of differential gene expression and pathway topology decomposition for obtaining pathway activation scores. Using Microarray Analysis Quality Control (MAQC) data sets and pretreatment data on Taxol-based neoadjuvant breast cancer therapy from multiple sources, we demonstrate that iPANDA provides significant noise reduction in transcriptomic data and identifies highly robust sets of biologically relevant pathway signatures. We successfully apply iPANDA for stratifying breast cancer patients according to their sensitivity to neoadjuvant therapy., Pathway analysis aids interpretation of large-scale gene expression data, but existing algorithms fall short of providing robust pathway identification. The method introduced here includes coexpression analysis and gene importance estimation to robustly identify relevant pathways and biomarkers for patient stratification.

Reactions of methyl 2-isothiocyanatobenzoate with hydroxylamine and alkoxyamines afforded earlier unknown 3-hydroxy-2-sulfanylquinazolin-4(3H)-one (1a) and 3-alkoxy-2-sulfanylquinazolin-4(3H)-ones (1b,c). Base-catalyzed reactions of compound 1a with alkyl halides were not regioselective, yielding O,S-dialkylation products. In the presence of acetic acid and sodium acetate, compound 1a was alkylated only at the S atom to give 2-alkylsulfanyl-3-hydroxyquinazolin-4(3H)-ones. Selective O-acylation of compound 1a at position 3 yielded 3-acyloxy-2-sulfanylquinazolin-4(3H)-ones.

3-Chlorosulfinylalkanoyl chlorides undergo cyclization into the corresponding five-membered mixed anhydrides (1,2-oxathiolan-5-one 2-oxides) under the action of sodium or mercury acetates. 2-Chlorosulfinylbenzoyl chloride gives 3H-2,1-benzoxathiol-3-one 1-oxide in high yield.

Spectrophotometric and thermal lens measurements showed that cw laser beam (450–530 nm, up to 100 mW) does not affect the absorption band of cytochrome c. Therefore, thermal lensing is used for determining cytochrome c (III) (c min = 1 × 10−7 mol/L at λ = 488.0 nm; c min = 3 × 10−8 mol/L at λ = 514.5 nm) and its active form, cytochrome c (II) (c min = 1 × 10−8 mol/L at λ = 514.5 nm). The enhancement of the sensitivity of determination of these species as compared with conventional spectrophotometry is more than two orders of magnitude. The optimal conditions for the formation of the NO complex of cytochrome c for its photometric determination were selected: the molar ratio of dodecyl sulfate (a modifying agent) to cytochrome c is 1: 30 at a working wavelength of 560 nm. When exposed to laser radiation, the nitrosyl complex of cytochrome c dissociates to form cytochrome c (III). The decomposition of this complex can be monitored by thermal lensing (514.5 nm) down to a level of 1 × 10−7 mol/L.

The facile general synthetic route to azidoalkylphosphonates by the nucleophilic substitution reaction in a series of bromoalkylphosphonates was elaborated, using 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) as a recyclable reaction medium. These azidoalkylphosphonates were used as intermediates for copper(I)-catalyzed regioselective 1,3-dipolar cycloaddition with a variety of alkynes to afford 4-substituted (1H-1,2,3-triazol-1-yl)alkylphosphonates as potential drug candidates. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:293–300, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20420

New alanine derivatives containing both the carboranyl and trifluoromethyl groups were synthesized by the reaction of organometallic derivatives of o-carborane with methyl trifluoropyruvate imines. When using the 1R-(−)-menthoxycarbonyl protecting group at the nitrogen atom, one of diastereomers was isolated and characterized. Trifluoromethyl-carboranylalanine methyl esters containing different protecting groups at the nitrogen atom were studied by X-ray diffraction. Both complete and partial deprotection of the amino and carboxy groups was performed.

An efficient general synthetic approach giving a facile, rapid and inexpensive access to a wide range of novel 1,2,3-triazoles bearing closo-dodecaborate fragment has been developed. The method is based on the nucleophilic cleavage of oxonium dodecaborate with NaN3 or tertiary propargylamine and subsequent Huisgen 1,3-dipolar cycloaddition ("click" methodology) of the cleavage products and organic acetylenes or azides.

2-Trifluoromethyl-substituted 1,2,3,6-tetrahydro-2-pyridyl carboxylates were synthesized in one step by the aza Diels—Alder reactions of methyl trifluoropyruvate sulfonyl- and phosphorylimines with 1,3-dienes.

To ensure a sulfur content on the level of 0.05–0.10 wt. % in catalytic naphthas, hydrotreating technology has been developed for hydrogenating primarily sulfur compounds and diolefin hydrocarbons. Monoolefinic hydrocarbons are converted to an insignificant degree, which preserves the high octane number of the naphtha obtained. The process is conducted at a pressure of 2–3 MPa, temperature of 250–350°C, and feedstock space velocity of 5–10 h−1. The possibility of “selective” hydrotreating of mixed catalytic and thermal naphthas was demonstrated. The technology has been industrially tested with positive results.

A preparative method for the synthesis of diethyl 1-diazo-2,2,2-trifluoroethylphosphonate from trifluoroacetic anhydride and benzyl carbamate via diethyl 1-benzyloxycarbonylimino-2,2,2-trifluoroethylphosphonate is developed. Optimum conditions for the chlorination of benzyl N-trifluoroacetylcarbamate with SOCl2—Py to afford the imidoyl chloride, phosphorylation of the latter under the conditions of the Arbuzov reaction, as well as diazotization of amino phosphonate with isopropyl nitrite are found.

Automotive gasolines and diesel fuels with improved environmental characteristics are produced at hydrotreating plants using finely granulated catalysts fabricated by impregnation technology, particularly series GP and GKD developed at the All-Russian Scientific-Research Institute on Petroleum Refining [1–4].

In resolving the question of how best ecologically clean diesel fuel (ECDF), extensive research has been performed at VNII NP with the active participation of Mazeikiai Nafta Joint Stock Company (Lithuania) and NORSI Joint Stock Company (Russia), aimed at working out the scientific principles of severe hydrotreating as applied to straight-run and mixed diesel fuel distillates.

Operating experience with the vacuum distillate hydrotreating section of the KT-1/1 unit has demonstrated the high efficiency of the GP-534 catalyst in the production of low sulfur cat cracker feed (sulfur content 0.35 % by weight maximum).

Single crystals of 2223 phase have been prepared by flux growth method from KCl. Their crystal structure is tetragonal (I4/mmm), a=3.82 A , c=37.06 A . Chemical composition of crystals as determined by EDAX was Bi2.00Pb0.27Sr1.62Ca1.92Cu3.18O10+δ. Microhardness measurements with Knoop indenter carried out on (001) pinacoid face show polar hardness anisotropy of between 0.9 and 1.33 GPa.

International audience; The reaction of fluorinated 1,6- and 1,7-enynes, containing the moiety N(PG)C(CF(3))(CO(2)R), with diazo compounds in the presence of [RuCl(cod)(Cp*)] (cod=cycloocta-1,5-diene, Cp*=C(5)Me(5) , PG=protecting group) as the catalyst precursor leads to the formation of fluorinated 3-azabicyclo[3.1.0]hexane-2-carboxylates and 4-azabicyclo-[4.1.0]heptane-3-carboxylates. This catalytic transformation was applied to various protecting groups and has proved to be a selective and a general synthetic tool to form constrained proline or homoproline derivatives in good yields. Z stereoselectivity of the created alkenyl group is obtained with N(2)CHSiMe(3), whereas N(2)CHCO(2)Et favours selectively the E configuration for the same double bond. The diastereoselectivity exo/endo depends on the size of the created ring. The X-ray structures of two products have been determined, showing the stereochemistry of the compounds. The reaction can be understood by initial [2+2] addition of the Ru=CHY bond, generated from diazoalkane, with the C≡CH bond of the enyne leading to a key bicyclic ruthenacyclobutane, which promotes the cyclopropanation, rather than metathesis. This selective formation of bicyclic [n.1.0] compounds results from the ruthenium-catalysed creation of three carbon-carbon bonds in a single step under mild conditions.