Role of Conformational Changes of Hexameric Bacterial Uridine Phosphorylases in Substrate Binding

Crystallography Reports - Crystals of mutants of uridine phosphorylase from Shewanella oneidensis MR-1 at the active-site threonine residue were obtained, and the three-dimensional structures of...     

Crystal Structure of Synthetic High-Chromium Analogue of Yimengite

Crystallography Reports - The structure of a potassium compound with the chemical formula K0.90Ti5.16Cr2.94Fe2.54Mg0.87Al0.22Mn0.30O19 has been investigated by single-crystal X-ray diffraction...     

Screening of Conditions that Facilitate Crystallization of Oligopeptidase B from Serratia Proteamaculans by Differential Scanning Fluorimetry

Crystallography Reports - Oligopeptidases B (OpdBs) are two-domain serine peptidases with trypsin-like substrate specificity belonging to the prolyl oligopeptidase family. These enzymes are...     

Synthesis of functionalized tetrahydropyridones by the tandem Knoevenagel—Michael—intramolecular ammonolysis—alkylation reaction

Russian Chemical Bulletin - The tandem Knoevenagel—Michael—intramolecular ammonolysis—alkylation reaction was used to synthesize functionalized tetrahydropyridones. The molecular...     

Unexpected formation of dinaphthoaza-17-crown-5 ether containing γ-aminopiperidine subunit

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Quantum-Chemical Simulation of the Structure of Charge-Transfer Complexes of 9,10-Phenanthrenequinone Nitro-Derivatives with Phenanthrene. Crystal and Molecular Structure of 1 : 1 Complex of 2,4,7-Trinitro-9,10-phenanthrenequinone with Phenanthrene

Russian Journal of General Chemistry - Data on the structure and properties of charge transfer complexes of nitro derivatives of 9,10-phenanthrenequinone (acceptor) with phenanthrene (donor) were...     

Reaction of methyl 2,4-dioxobutanoates with tetracyanoethylene

Reaction of methyl 2,4-dioxobutanoates with tetracyanoethylene yielded methyl 3-acyl-4-cyano-5-(dicyanomethylene)-2-hydroxy-2,5-dihydro-1H-pyrrole-2-carboxylates. X-Ray diffraction data showed that 3-acyl-4-cyano-5-(dicyanomethylene)-2-hydroxy-2,5-dihydro-1H-pyrrole-2-carboxylic acid methyl esters can form supramolecular structures with one-dimensional channels which make possible inclusion of large organic and bioorganic molecules.     

Reaction of 1-(2-Oxocyclohexyl)ethane-1,1,2,2-tetracarbonitrile with α,β-Unsaturated Aldehydes

Russian Journal of General Chemistry - The reaction of 1-(2-oxocyclohexyl)ethane-1,1,2,2-tetracarbonitrile with crotonic aldehyde, cinnamic aldehyde, 2-furylacrolein, 3-phenyl-2-propinal,...     

Origination and Transformation of the Monoclinic and Orthorhombic Phases in Reactor Powders of Ultrahigh Molecular Weight Polyethylene

Using powerful synchrotron X-ray radiation of the beamline “Belok” operated by the National Research Center “Kurchatov Institute,” we perform X-ray diffraction (XRD) study of an intact, virgin (not subjected to any external mechanical loads) particle isolated from reactor powder of ultrahigh molecular weight polyethylene. Along with the peaks originating from the orthorhombic phase, we detect the peaks characteristic of the monoclinic phase that is stable only under mechanical stress, suggesting that the mechanical stress that leads to the formation of the monoclinic phase and persists at room temperature develops during the polymer synthesis. The monoclinic phase gradually disappears when the particle is heated stepwise in increments of 5 K, and its peaks become undetectable when the temperature reaches 340 K. We contrast the results obtained for the phase composition of the virgin particle to those for a tablet prepared by compaction of the same reactor powder at room temperature. XRD analyses of the tablet were performed on D2 Phaser (Bruker) instrument. The monoclinic phase that originates during the polymer synthesis and the one that forms in the tablet during compaction have different parameters. We discuss the mechanisms by which these two different monoclinic phases originate during the processes involved.