Chemistry

Qualitative and Quantitative Estimation of Intramolocular Hydrogenic Communication in a Row of Orto-R-phenyl-substituted Tetrazolohexahydroquinazolines

The onе-pot interaction of C-aminotetrazole, cyclohexanone and o-R-benzaldehydes (in contrast to unsubstituted benzaldehyde benzaldehyde) leads to the formation of additionally linear tetrazohexahydroquinazolines, their isomers with an angular articulation of the rings. The appearance of isomers with angular articulation of the rings can be explained by the total influence of the spatial and electronic effects, and the influence of the low-energy interaction by the type of hydrogen binding NH ··R (VVS) can not be ruled out.

Synthesis and Ways of Formation of Hydroxyphenyl Substituted Benz[4,5]imidazole-1,2,3,4,5,6- hexahydro[1,2-a]quinazolines

To synthesize new potentially biologically active benzimidazoloquinazolines, a three-component condensation of 2-aminobenzimidazole, cyclohexanone and hydroxylatedbenzaldehydes was studied. The reaction proceeds regioselectively when the equimolar ratios of the reagents are boiled for 3 hours in N,N-dimethylformamide and is accompanied by the formation of ortho-phenyl substituted hexahydrobenz[4,5]imidazolo [1,2-a]quinazolines having an angular articulation of the rings and a different number and position of hydroxyl groups in the phenyl substituent.

Transformation of a Stable Catalyst of Catalytic Riforming Facility with Using the Catalyst R-98

One of the most important tasks of modern refineries is the modernization of existing plants to increase production and improve the quality of the commodity. In this connection, the catalytic activity of the industrial catalyst of the reforming pro- cess R-98 (containing in its composition platinum and rhenium, in the amount of 0.25% by weight of each) in the conversion of a stable catalyst was studied. Stable catalyst is released from the stabilizer column of the catalytic reforming unit.

Phase Equilibrium for the System KH2PO4 – K2SO4 – H2O at 25°С

Potassium dihydrogen phosphate is widely used in industrial and agri- culture. The solvent extraction method for producing KH2PO4 from the more cheap extraction phosphoric acid and potassium chloride has gained growing attention recently. To evaluation influence SO42– on the crystallization KH2PO4 it is nessesary comprehensive knowledge of the phase equilibria in the system K+// H2PO42–, SO42– – H2O. The ternary system KH2PO4 – K2SO4– H2O was determined at 25 °C by the improved isothermal method of section.

Phase Equilibria in the Ternary System “Potassium Iodide – Water – Tert-Butyl Alcohol” within 5–30°C

Studying of the influence of the salt nature and temperature on the liquid-liquid equilibrium in the ternary systems “salt – binary solvent” is topical for the development of the salting-in–salting- out theory. In addition, the ternary potassium iodide-water-alcohol systems are constituents of the quaternary iodine – potassium iodide – water – alcohol ones, studying of which is of practical interest in terms of determining the mixed solvent compositions with the highest iodine-dissolving power.

On Interaction of Synthetic Food Dye E133 with Cetylpiridinium Cations

Synthetic food colorings (SPK) are widely used to impart consumer properties to food. But. many of them are allergens. Therefore, their definition in food objects is relevant. The rapid method of determining the SPK is ionometry. It is based on the use of ion- selective electrodes. Such an electrode for determining the food coloring E133 is not described in the literature. The purpose of this work is the study of the ionophore. Used to determine the E133 in a variety of food products.

Luminescent Properties of Doxycycline in the Presence of Silver Nanoparticles Modified by Ions of Europe

Fluorescence spectroscopy is a routine tool for studying cellular and molecular visualization, flow cytometry, medical diagnosis, forensic medical examination, genetic analysis, and also an analytical method. However, most available organic dyes used to produce an optical signal have a number of important limitations, such as hydrophobicity, low quantum yield, and low photostability.

Equilibrium Liquid–Liquid–Solid and Critical Phenomena in the Quaternary System Cesium Nitrate+Water+Pyridine+Butyric Acid with in the Range of 5 to 60°C

Phase equilibria and critical phenomena in the component mixtures of a cut of the composition tetrahedron of the quaternary system cesium nitrate + water + pyridine + butyric acid were studied in the range of 5–60°C by the visual-polythermic method. The phase equilibria in the component mixtures were studied using sections of one cut of the composition tetrahedron. The cut position was chosen in such a way as to cross all figures of the phase states with the presence of a solid phase in order to observe the phase behavior of the monotectic state figure as temperature changes.

Antioxidant Status of Macrobasidiomycetes Mycelium Grown in the Presence of Organoselenium Compounds

Antioxidant status maintenance plays a significant role for mushroom cultures in respect to oxidative stress resistance, cytodifferentiation and transition to the generative stage. Strong antioxidants are the selenium compounds. One of the antioxidant action indices is the antiradical activity determined by means of the spectrophotometric method using the reactions with the free radical 1,1-diphenyl-2-picrylhydrazyl (2,2-diphenyl-1-picrylhydrazyl, N,N-diphenyl-N’-picrylhydrazyl, DPPH) (C6H5) 2N– N•–C6H2(NO2) 3-2,4,6.

Chemometric Method of PLS in the Treatment of Titrimetric Data when Opredeleniye of Arginine and Lysine in Mixed Solutions

Arginine and lysine are the most important α-amino acids that are part of many proteins, which play an important role in the processes of nitrogen metabolism, growth and restoration of body tissues. It is used in medical nutrition in the postoperative recovery period, as well as as diagnostic factors. The simple express methods of separately determining the main α-amino acids of arginine and lysine in their mixed solutions are in demand.

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