Reaction of Disodium Ethene-1,1-bis(thiolates) with Dibromobutanes

Russian Journal of Organic Chemistry - Previously unknown 2-(1,3-dithiolan-2-ylidene)malononitrile, 2-cyano-2-(1,3-dithiolan-2-ylidene)­acetamides, and methyl...     

Quaternary size distribution of soluble aggregates of glutathione-S-transferase-purified viral protein as determined by asymmetrical flow field flow fractionation and dynamic light scattering

Polyomavirus VP1 protein in pentamer form was expressed in E. coli and purified using glutathione-S-transferase (GST) affinity chromatography. Purified GST-tagged protein was found to exist as soluble aggregates with a size distribution of 1-52 tagged pentamers (340-1800 x 10(3)kDa), as determined by asymmetrical flow field flow fractionation with multiple angle light scattering (AFFFF-MALS). Aggregation did not inhibit tag removal by enzymatic cleavage, implying that the quaternary structure of the VP1 pentamers had been maintained. Elution gel filtration (EGF) was utilized to prepare a solution enriched with protein small enough to access resin pores (LMWe) as well as solution enriched with protein excluded from resin pores (HMWe). Material size distributions within both solutions were determined using AFFFF-MALS (radius of gyration LMWe: 5-10nm; HMWe: 10-35 nm) and dynamic light scattering (DLS) (hydrodynamic diameter LMWe: 10-90 nm; HMWe: 20-300 nm). DLS and AFFFF-MALS analysis of each fraction of affinity chromatography purified material identified the elution profiles of large and small aggregate structures. DLS readings of all fractions were significantly affected by the presence of high molecular weight aggregates, with Z-average hydrodynamic diameter values reflecting the mass ratio of large and small aggregate structures in a solution. The methods utilized in this study have the potential to be used during chromatographic purification of all proteins that exist as soluble aggregates to determine size distribution. The finding that GST-tagged viral proteins exist as soluble aggregates has implications for existing immunological studies that utilize them.     

Synthesis of 2,7-Diazabicyclo[3.2.1]oct-3-ene Derivatives

Russian Journal of Organic Chemistry - Tetracyanoethylene adducts with ketones, 4-oxoalkane-1,1,2,2-tetracarbonitriles reacted with hydrogen chloride or phosphorus(III) chloride in 1,4-dioxane to...     

Reaction of Disodium Ethene-1,1-bis(thiolates) with 1,1,2-Trichloroethane

Russian Journal of Organic Chemistry - Previously unknown chloro-substituted 1,3-dithiolanes were synthesized by reaction of disodium 2-cyanoethene-1,1-bis(dithiolates) with 1,1,2-trichloroethane....     

Synthesis of some 2-ylidene-1,3-dithiolanes

Russian Journal of Organic Chemistry - Convenient procedures have been developed for the synthesis of 2-(1,3-dithiolan-2-ylidene)- malononitriles and 2-cyano-2-(1,3-dithiolan-2-ylidene)acetamides...     

Tricomponent domino synthesis of 6-hydroxy-2-chloro-1,4,5,6-tetrahydropyridine-3,4,4-tricarbonitriles

In reaction of tetracyanoethylene with ketones and HCl in 1,4-dioxane at 30–40°? 6-hydroxy-2-chloro-1,4,5,6-tetrahydropyridine-3,4,4-tricarbonitriles are formed.     

Targets for studying the dynamic and radiative properties of material with laser facilities

The technology of target preparation for direct and indirect laser irradiation is developed to study the shock compressibility of materials on the Sokol-2 and Iskra-5 laser facilities. Copper and aluminum films with a density close to that of the bulk materials are prepared by ion-beam deposition. The difference in the densities of the film and bulk materials is 0.8–1.7%, and the accuracy of density measurement is 0.4–1.5%. Processes for the preparation of porous materials (aluminum, copper, nickel, gold, etc.) are also devised. Porous cop-per samples of thickness 10–50 μm, pore size 0.1–5.0 μm, mean density 0.065–0.4 g/cm³, and porosity 20–140 are obtained. The preparation of freely suspended film targets 0.1–0.2 μm thick that are irradiated by picosecondlaser shots on the Progress-P and élas-PS facilities is described.     

A New Technique for Synthesis of Nordstrandite

Basic physicochemical characteristics of aluminum trihydroxide prepared for the first time bycarbonization in the form of nordstrandite are described. Silicon-containing complexes present in the solution being carbonized act as stabilizers of the nordstrandite structure in the course of hydroxide precipitationfrom aluminate solutions.     

Specific Features of the Composition of Solid Phases in the Na+K+Ca2+∥CO 3 2- OH--H2O System

The composition of solid phases in the Na⁺K⁺Ca^{2 +}CO₃ ^{2 -}OH^--H₂O system at 95°C was studied. Triple carbonates of alkali metals and calcium, different from the known synthetic and natural compounds, were found in the system.     

Operator algebras and lattices of invariant subspaces. I

For a bounded linear operator T one considers questions regarding the commutativity of the commutant {T}, the possibility of approximation in the weak operator topology of the operators from the bicommutant {T}, reflexivity, the equality of other operator algebras and lattices of subspaces, connected with the operator T. One gives the answers to these questions for operators from certain classes (C_o-contractions; weak contractions, contractions having finite defect index, etc.).Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akademii Nauk SSSR, Vol. 178, pp. 23–56, 1989.