Russian Chemical Bulletin最新文献

Three-component (ternary) microgels based on carboxymethylcellulose and copper(ii) ions with the immobilized inhibitor of inducible NO synthase (N-(5,6-dihydro-4H-1,3-thiazin-2-yl)benzamide), as well as the activator of this enzyme (N-(4-isopropylphenyl)-N-(1-iminoethyl)piperidine-1-carbothioamide hydrobromide) were prepared. The hydrodynamic and electrokinetic characteristics of the microgels were studied and demonstrate an optimal size and high colloidal stability in both aqueous and physiological environments. The synthesized ternary microgels are characterized by high cytotoxicity causing apoptosis of leukemic Jurkat cells.

The reaction of hexamethylenetetramine (CH₂)₆N₄ with sparingly soluble (1-hydroxyethylidene)diphosphonates M(H₂L)•2H₂O (M = Mn, Co, Zn; H₄L is (1-hydroxyethylidene)diphosphonic acid) afforded water-soluble compounds of the composition [(CH₂)₆N₄H₂]ML•2H₂O (M = Mn (1), Co (2), Zn (3)). Manganese derivative 1 lost its solubility during storage, whereas the cobalt and zinc compounds retained it. The tetrafunctional base hexamethylenetetramine reacts with tetrafunctional (1-hydroxyethylidene)-diphosphonic acid H₄L in methanol to form hexamethylenetetraminium (1-hydroxyethylidene)diphosphonate dihydrate [(CH₂)₆N₄H]⁺(H₃L)•2H₂O (4). When heated in an aqueous methanol medium, compound 4 dissociates to acid H₄L and base (CH₂)₆N₄, hexamethylenetetramine reacts with water to produce ammonia and formaldehyde, and the acid H₄L and ammonia generate diammonium (1-hydroxyethylidene)diphosphonate (NH₄)₂H₂L. The heating in an inert atmosphere causes the extensive decomposition of compound 4 giving a non-volatile water-soluble residue and a series of volatile organic compounds, such as amines, amides, amino alcohols, and amino acids. The obtained compounds were studied by IR spectroscopy, elemental analysis, powder X-ray diffraction, and thermogravimetric analysis. The molecular structure of diammonium (1-hydroxyethylidene)diphosphonate (NH₄)₂H₂L was determined.

The structure and photophysical properties of the luminophore 4′-butyl-4-propyloxysalicylideneaniline (1) were studied by X-ray diffraction analysis and differential scanning calorimetry. At room temperature, compound 1 does not luminesce. According to the DSC data, compound 1 undergoes a crystal—mesophase phase transition at 54.1 °C and it melts at 68.4 °C, being transformed into an isotropic melt. When cooled to 67.9 °C, the isotropic melt becomes turbid due to the formation of a mesophase. A yellow fluorescence of the sample is achieved under UV irradiation, it intensifies on further cooling, persists at room temperature for about a week, and then fades. The mechanical action triggers the growth of luminescent crystals (1′). The X-ray diffraction study of original non-luminescent crystal 1 and luminescent crystal 1′ demonstrated that they are structurally identical. The possible cause of the difference in the photophysical properties of crystals 1 and 1′ is discussed. It is based on dynamic processes leading to a shift of the prototropic equilibrium toward either the benzenoid or quinoid configuration of the bonds in the azomethine moiety.

The sequential and combined sorption of bovine serum albumin (BSA) and copper ions on nanohydroxyapatite (HAP) changes the sorption capacity and sorption mechanism and affects the sorption reaction constants. Ligands, effectors of NO synthase N-(5,6-dihydro-4H-1,3-thiazin-2-yl)benzamide (iNOS inhibitor, L¹) and N-(4-isopropylphenyl)-N-(1-imminoethyl)piperidine-1-carbothioamide hydrobromide (NOS activator, L²), are not sorbed on HAP. However, the CuL¹₂Cl₂ complex shows weak binding to HAP possibly due to a higher sorption capacity of copper ions, which can displace calcium ions.

A number of dimethylaminoalkyl esters of butanoic and pentanoic acids were obtained by the acylation reaction of N,N-dimethylaminoalkanols. 3-(Dimethylamino)propyl butanoate, 3-(dimethylamino)ethyl- and 2-(dimethylamino)propyl pentanoates are described for the first time. The structures of all synthesized compounds are confirmed by NMR spectroscopy and elemental analysis. 2-(Dimethylamino)ethyl pentanoate and 3-(dimethylamino)propyl pentanoate are obtained in 66% yield. It was found using the data of DTA, FTIR spectroscopy, as well as taking into account the value of the gel-fraction content in the cured compositions, that with a decrease in the length of the hydrocarbon fragment linked to nitrogen and oxygen atoms, and with an increase in the total nitrogen content in the amino ester molecule, the activity in the epoxy resin curing reaction increases. An assessment of the bonding strength of St3 steel and aluminum alloy D16 with ED-20 epoxy resin cured with amino esters demonstrated that all synthesized compounds provide more effective bonding than the standard polyethylene polyamine hardener.

The heterocyclization reaction of mixed phosphonium-iodonium ylides with alkynes in the presence of various dipolarophiles was studied in order to identify the dependence of the process result on the dipolarophile nature. The library of phosphinolines and phosphonium-substituted furans obtained under the conditions of this process was expanded. The studies, including quantum chemical calculations, were conducted to reveal the influence of the nature of substituents in the iodonium fragment on the reactivity of mixed ylides in heterocyclization reactions. The antiproliferative activity of new compounds was studied and phosphonium-substituted furans were found in some cases to demonstrate higher activity in human cancer cell lines compared to cisplatin.

A study of electrochemical separation of pure H₂ from hydrogen-containing gas mixtures is described. Use was made of a hydrogen pump containing a polymer proton exchange membrane based on polybenzimidazole. A high degree of recovery of pure hydrogen from gas mixtures containing carbon oxides, methane, and nitrogen was demonstrated. The current-voltage characteristics of the hydrogen pump were analyzed, and the energy efficiency of electrochemical separation of hydrogen from carbon oxides, methane, and nitrogen was estimated.

A methos for the synthesis of triazeneoxidoacetic acid chloride from 1-hydroxy-3,3-dimethyl-1-triazene 2-oxide sodium salt and haloacetic acid esters was developed. Preliminary reactivity studies of the synthesized acid chloride were performed. The products synthesized based on this acid chloride can be potential nitric oxide donors in living organisms.

Visible light-assisted (λ = 465–470 nm) reactions of (phenyl)(trifluoromethylsulfonylimino)-λ³-iodane with alkenes gave products of sulfonamidation and cyclization. Solvent effect on the product composition was revealed. A comparison of the reactions of the title iodane with cyclohexene carried out in the presence of N-halosuccinimides and under blue LED-light-activation conditions (440–450 nm) revealed the differences in triflamidation reaction producing cyclic (aziridine) and linear (halo amides, halo amidines) products. Plausible reaction mechanisms were discussed.

4-Oxo-4,5,6,7-tetrahydrobenzofurazan, which is easily synthesized from cyclohexanone, can be efficiently converted to 4-(2-carboxyethyl)- and 4-[3-(E)-hydroxyimino)-3-nitropropyl]furazan-3-carboxylic acids by the oxidation with nitric acid. Subsequent alkaline oxidation provides a route to furazan-3,4-dicarboxylic acid.