Volume 76, Issue 9

Synthetic protocols for the palladium-catalyzed arylation of various linear and cyclic polyamines and polyoxapolyamines has been worked out. Pd(0) and Pd(II)complexes with such phosphine ligands as dppf, BINAP, PPF-OMe, P( t Bu) 3 ,2-di tert -butylphosphino-1,1'-biphenyl have been explored in the catalytic amination reactions. Monoamination of chloro-, bromo-, and iodoarenes with di-, tri-, and tetraamines have been carried out, conditions for di- and polyarylation of linear polyamines have been elaborated. Successful arylation of 1,4,7,10-tetraazacyclododecane (cyclene) and 1,4,8,11-tetraazacyclotetradecane (cyclam) have been conducted. Intramolecular diamination of dihaloarenes such as 1,2-dibromobenzene, 2,6-dichlorobromobenzene, 1,3-dibromobenzene, 1,8-dichloroanthracene, 1,8-dichloroanthraquinone, 1,5-dichloroanthracene, and 1,5-dichloroanthraquinone afforded corresponding polyazamacrocycles containing arene moieties. For the first time, a convenient one-pot synthesis of the face-to-face arranged bismacrocyclic systems has been carried out.

The review surveys the reactions of electron-deficient azaaromatic compounds with mono- and bifunctional nucleophilies in which a nucleophilic attack at the unsubstituted CH carbon of an aromatic ring is one of the key steps. Use of the S N H methodology for the synthesis of fused heterocyclic systems by means of nucleophilic addition –addition A N –A N , addition –substitution of hydrogen A N –S N H , tandem substitution of hydrogen S N H –S N H , and other strategies will be discussed. Intramolecular S N H reactions will also be considered as effective synthetic tools to obtain condensed heterocyclic systems.

The review surveys new data on the directed construction of supramolecular organic–inorganic compounds from macrocyclic cavitand cucurbit[6]uril (C 36 H 36 N 24 O 12 )and mono- and polynuclear aqua complexes. Due to the presence of polarized carbonyl groups, cucurbit[6]uril forms strong complexes with alkali, alkaline earth and rare-earth metal ions, and hydrogen-bonded supramolecular adducts with cluster and polynuclear aqua complexes of transitional metals. A wide variety of supramolecular compounds and their unique structures are described.

Two series of composite micro/mesoporous materials with different contributions of micro- and mesoporosity were prepared by dealumination and recrystallization of mordenite zeolite. The materials were characterized by X-ray diffraction, infrared spectroscopy, 27 Al magic angle spinning (MAS) NMR, nitrogen adsorption–desorption, and temperature-programmed desorption of ammonia (TPD NH 3 ). Catalytic properties were studied in transalkylation of biphenyl with diisopropylbenzene. Both types of composite materials showed remarkably high activity, stability, and selectivity toward formation of di-isopropylbiphenyls with respect to both pure microporous and mesoporous materials. The effect is due to high zeolitic acidity combined with improved accessibility of active sites and transport of bulky molecules provided by mesopores.

The results of many years of collaborative research by chemists and immunologists in the area of application of synthetic polyelectrolytes in immunology are reviewed. Linear synthetic polyelectrolytes with diverse structures (which are not structural analogs of biopolymers and, hence, not antigenic because they are unknown to the immune system), when introduced into the organism, noticeably intensify the formation, migration, and dissemination of stem cells, which are precursors of all specialized cells including functional immune cells. In addition, synthetic polyelectrolytes, when introduced in mixtures with typical antigens (proteins, natural microbial polysaccharides, and their synthetic analogs), serve as immunostimulants enhancing immune response by several times. Moreover, individual bacterial or viral antigens, not sufficiently active by themselves, induce specific immune response enhanced by orders of magnitude if chemically bound to synthetic polyelectrolytes. Such conjugates being preliminarily administrated, protect organisms from absolutely mortal doses of the corresponding bacteria or viruses. The nontoxic immunostimulant was developed: the ternary copolymer of 1,4-ethylenepiperazine,1,4-ethylenepiperazine- N -oxide, and ( N -carboxymethylene)-1,4-ethylenepiperazinium bromide (brand name “polyoxidonium ”™) permitted for human administration. The conjugate of polyoxidonium with hemagglutinin and neuraminidase, protein subunits of influenza viruses, has appeared as the first non-Pasteurian vaccine, which now is successfully used in Russia (about 50 million immunized people for the last 7 years). The physicochemical mechanisms of the biological effect of these compounds and challenges of the further use of the approach developed are considered in the review.

The analysis of modern nickel-based superalloys evolution for casting single-crystal turbine blades was performed. The influence of rhenium as a new alloying element on the physicochemical, kinetic, and structural parameters of nickel-based superalloys and phase stability is discussed. The following experimental data are generalized: the coefficients of segregation and distribution of alloying elements in nickel-based superalloys gamma- and gamma'-phases, the influence of alloying elements on the melting temperature, gamma- and gamma'-phases crystal lattice parameters, diffusion rate of atoms and probability of topologically close-packed (TCP) phase formation. The principles of the balanced alloying and computerized design method for developing fourth-generation single-crystal nickel-based superalloys with high Re content (9 –10 %) are considered. The role of high gradient directional solidification (200 –220°C cm –1 ) in producing single-crystal turbine blades of nickel-based superalloys with high Re content is discussed.

Monocyclic rearrangements of azoles are extensively studied as alternative methods for the preparation of new heterocyclic systems. The present work is devoted to investigation of monocyclic and cascade rearrangements of 1,2,5-oxadiazole 2-oxide (furoxan) derivatives. It was found during investigations that rearrangements of furoxan ring had some peculiarities in comparison with analogous rearrangements of other azoles. Therefore, three different kinds of rearrangements were found. The first of them occurred through a dinitroso-ethylene intermediate and resulted in the synthesis of 1,2,3-triazole 1-oxides [oximes of 5-acetyl-4-phenyl(methyl)-2-phenyl-2 H -1,2,3-triazole 1-oxides and 2-(furoxan-4-yl)-4-nitro-5-R-2 H -1,2,3-triazole 1-oxides ]by thermal recyclization accordingly of 3-methyl-4-acetyl(benzoyl)furoxans phenylhydrazones and 3,3'-(R)-disubstituted-4,4'-azofuroxans. The latter reaction was performed in an oxidizing medium. The second kind of rearrangement (classical variant) was the synthesis of new azoles containing the 1-nitroalkyl substituent. These rearrangements were performed using three examples: base-induced interconversion of furoxanyl ketone phenylhydrazones into 5-(1-nitroalkyl)-2 H -1,2,3-triazole derivatives and of 1-alkyl(aryl)-3-(furoxan-4-yl)amidines into 1-substituted 3-(1-nitroalkyl)-1,2,4-triazoles as well as a thermally induced rearrangement of 4-thioureido-3-R-furoxans into derivatives of 5-amino-3-(1-nitroalkyl)-1,2,4-thiadiazole including (5-amino-1,2,4-thiadiazol-3-yl)nitro-formaldehyde arylhydrazones (where R =N=N –Ar). Rearrangements of the third kind were those of the cascade type. Three new cascade rearrangements of azofuroxan derivatives [3,3'-azo-4,4'-bis(acetylamino)furoxans, 3-arylazo-4-acetylaminofuroxans, and 3-arylazo-4-(3- ethoxycarbonylureido)furoxans] into 4-amino-5-nitro-2 H -1,2,3-triazole derivatives were discovered. These three reactions were assumed to include two consecutive (cascade) rearrangements: a 1,2,4-oxadiazole ring was formed at the first step and then transformed into a 1,2,3-triazole ring with the participation of an azo group.

The driving force for the constant improvement and development of synthetic methodologies in carbohydrate chemistry is the importance of natural oligosaccharide chains in numerous biological phenomena such as cell growth, differentiation, adhesion, etc. Here, we report our syntheses of the spacer-armed oligosaccharides of sialylated lacto - and neo- lacto -, globo -, ganglio- , and sulfoglucuronylparagloboside-series, which include new rationally designed synthetic blocks, efficient solutions for the stereoselective construction of glycosidic bonds, and novel protection group strategies.

One of the fundamental outcomes of nuclear theory is the predicted existence of increased stability in the region of unknown superheavy elements. This hypothesis, proposed more than 35 years ago and intensively developed during all this time, significantly extends the limits of existence of chemical elements. “Magic ”nuclei with closed proton and neutron shells possess maximum binding energy. For the heaviest nuclides, a considerable stability is predicted close to the deformed shells with Z = 108, N = 162. Even higher stability is expected for the neutron-rich nuclei close to the spherical shells with Z = 114 (possibly also at Z = 120, 122) and N = 184, coming next to the well-known “doubly magic ”nucleus 208 Pb. The present paper describes the experiments aimed at the synthesis of nuclides with Z = 113–116, 118 and N = 170–177, produced in the fusion reactions of the heavy isotopes of Pu, Am, Cm, and Cf with 48 Ca projectiles.The energies and half-lives of the new nuclides, as well as those of their daughter nuclei (Z < 113) qualitatively agree with the theoretical predictions. The question, which is the nucleus, among the superheavy ones, that has the longest half-life is also considered. It has been shown that, if the lifetime of the most stable isotopes, in particular, the isotopes of element 108 (Hs), is ≥ 5 ×10 7 years, they can be found in natu ral objects. The experiments were carried out during 2001–2003 in the Flerov Laboratory of Nuclear Reactions (JINR, Dubna) in collaboration with the Analytical and Nuclear Chemistry Division (LLNL, Livermore).

Physicochemical foundations of various processes which comprise the single stages of natural gas processing into motor fuels are considered. Among them are: novel process of syngas production by methane reforming using rocket technology, direct dimethyl ether synthesis from syngas and its conversion into the ecologically benign gasoline, an advanced technology of methanol synthesis, as well as methanol transformation into pure hydrogen, Fischer–Tropsch synthesis with increased selectivity. New developments made by the Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences (TIPS RAS) in this field are discussed. In this light, the achievement of a global goal, to make synthetic motor fuels cheaper than their oil counterparts, appears to be a solvable task for the nearest future.

The existence of a tide relationship between fundamental chemical properties of either copper or manganese as 3d transition elements and advanced functional properties of related oxide materials is demonstrated using original experimental results. The complex role of ionic sizes, oxidation and spin states, and Jahn–Teller distortions is discussed in terms of the influence of these phenomena on the crystal structure, phase assemblage, microstructure, and physical properties of three key classes of modern copper- and manganese-containing materials (high-temperature superconductors, colossal magnetoresistive compounds, and 1d superionics), bringing up innovation technologies in electrical power engineering, micro- electronics, spintronics, magnetic field sensing, electrode materials, and fuel cells.

Thermoprogrammed desorption of H 2 from [TiFe 0.95 Zr 0.03 Mo 0.02 ]H 2 showed two forms of absorbed hydrogen. The first one is evolved from the intermetallic hydride under heating up to 185 °C under Ar (loosely bound hydrogen, LBH). The second portion of H 2 (strongly bound hydrogen, SBH) remains in the intermetallic hydride up to 700–920 °C. SBH reacts with CO 2 to give CO rather selectively (80–99 %) at CO 2 conversion of 50–70 % at 350 –430 °C and 10 –12 atm. Dehydrogenation of cyclohexane coupled with CO 2 hydrogenation into CO predominantly proceeds efficiently in the presence of the intermetallic hydride [TiFe 0.95 Zr 0.03 Mo 0.02 ]H x (where x = 0.1) in a combination with industrial Pt/Al 2 O 3 catalyst. Aliphatic primary alcohols undergo oxidation by CO 2 forming aldehydes in the presence of [TiFe 0.95 Zr 0.03 Mo 0.02 ]H 0.36 . Conversion of the alcohols into alkanes with carbon skeleton counting at least doubled carbon number in comparison with parent alcohol was found to be catalyzed by the mixture of the last intermetallic hydride and Pt/Al 2 O 3 catalyst.

New trends in chemistry induced by genetic engineering and genomic information are analyzed. Genomic information and bioinformatics make the identification of all molecular participants of biological processes possible. The methods of identification of enzyme-active sites from sequence data were demonstrated. The problems of "chemical proteomics" were formulated and analyzed. New biocatalytic processes based on a new generation of enzymes, including CO 2 reduction and enzyme fuel cell construction, are demonstrated. It was shown that in many reactions the enzymes are substantially more efficient in comparison with classical chemical catalysts. The creation of recombinant proteins from unnatural amino acids is demonstrated, and organisms containing such proteins are described. The new trends of proteomics and bioanalytical chemistry in the postgenomic era are discussed.

This document describes the introduction of the concept of property in the field of molecular biology for the presentation of results of clinical laboratory investigations of genes and mutations. It follows the IUPAC–IFCC systematic rules and attempts to create a common base for communication between the clinical laboratory sciences, the medical practitioner, and the molecular biology areas of knowledge. Because of the plethora of possible structural variations in the outcome of analysis, the designation of components is restricted to the symbols of genes as identified by the Human Genome Nomenclature Database (HUGO). The listing of properties having DNA as system comprises all symbols in the HUGO database except for symbols related to mitochondrial genes, while properties having RNA as system are included only when known to be in actual use. The detailed and accurate presentation of results is made by the laboratory performing the study, and it is recommended that the explicit guidelines given by Antonarakis and den Dunnen be adhered to. For electronic communication, a code (NPU) is allocated to each property identified. The complete list of properties, which is an integral part of this report, can be accessed at <www.iupac.org/publications/pac/2004/7609/7609x1799.html>.