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Sequential reaction of cyclohexanone with malononitrile and 2-aminopropene-1,1,3-tricarbonitrile in the presence of potassium hydroxide or sodium ethylate in ethanol gave 4-imino-2-(dicyanomethylene)-3-azaspiro[5.5]undecane-1,5-dicarbonitrile. The latter reacted with primary amines and an excess of formaldehyde to form new 2-(dicyanomethylene)-3,7-diazaspiro[bicyclo[3.3.1]non-3-ene-9,1′-cyclohexane]-1.5-dicarbonitrile derivatives. Contrary to the literature data, the reaction of cyclohexanone with 2-aminopropene-1,1,3-tricarbonitrile in benzene in the presence of piperidine and glacial acetic acid led to the formation of 2,4-diamino-5,6,7,8-tetrahydronaphthalene-1,3-dicarbonitrile. [ABSTRACT FROM AUTHOR]

The reaction of 2-amino-1,1,3-tricyanopropene (malononitrile dimer) with isothiocyanates leads to 1-substituted 4,6-diamino-2-thioxo-1,2-dihydropyridine-3,5-dicarbonitriles or 4,6-diamino-2-(phenylimino)-2H-thiopyran-3,5-dicarbonitrile, depending on the conditions. Quantum-chemical modeling of the IR spectra and reaction routes for the synthesized compounds was carried out. In silico predictive analysis of potential protein targets, compliance with bioavailability criteria, and ADMET parameters was performed. [ABSTRACT FROM AUTHOR]

A number of europium(III), terbium(III), and gadolinium(III) coordination compounds with N-substituted phthalamic acids were synthesized. Composition and structure of the ligands and the obtained complex compounds were confirmed by NMR and IR spectroscopy and thermogravimetric analysis. It was found that terbium(III) and europium(III) coordination compounds with N-phenylphthalamic acid possess the most pronounced luminescence. [ABSTRACT FROM AUTHOR]

The reaction of aromatic aldehydes with malononitrile, ethyl or butyl cyanoacetate and acetylacetone in the presence of NaOH under mild conditions (EtOH, 25°C) led to the formation of new series of (1S,5R,6R,9R)/(1R,5S,6S,9S)-2-amino-6,9-diaryl-7-acetyl-8-methyl-4-oxo-5-cyano-3-azabicyclo[3.3.1]nona-2,7-diene-1-carboxylic acids esters. A plausible mechanism of the cascade reaction was proposed. [ABSTRACT FROM AUTHOR]

This paper is devoted to experimental study of fine boring of steels, which improves performance and parameters of processing accuracy. The conditions that ensure high wear resistance of cutting blades and improvement of accuracy parameters and processing quality were determined by changing cutting conditions and special geometry of carbide cutters with chip-curving chamfers. In the experiments, single-cutter boring was used, as well as double-cutter according to the feed division method. On the basis of the method of planning an experiment in the presence of a large number of variable input parameters, rational values of speed, feed, depth of cut, as well as parameters of roughness, taper and deviations from the roundness of the machined holes are established. The effect of fine boring modes on wear and tool life of cutting edges has been clarified. The influence of the compliance of cantilever boring bars on the level of oscillation of the cutter was also studied. It was found that intense vibrations occur for boring bars of small diameter <10 mm at a depth of cut >0.1 mm, resulting in intensive wear of the cutters. In preliminary experiments, it was found that boring of soft parts (type 20X and steel 30) is significantly different from machining harder steels and requires the use of other cutting conditions. Although the groups of structural carbon, high-quality and alloy steels may differ insignificantly in terms of processing conditions and the results achieved in the process of fine boring, however, for processing steels with special properties, a distinctive feature arises, namely increase in the level of vibrations with increasing cutting speed within the range usually used for other steels. This paper shows results of an experimental study of the process of thin boring of 35L steel with cutters made of TЗ0K4 hard alloy and chip-curving chamfers along the cutting blades. [ABSTRACT FROM AUTHOR]

The reaction of (2E,4E)-5-phenyl-2-cyano-2,4-pentadienethioamide or (E)-3-(2-nitrophenyl)acrolein and cyanothioacetamide with α-bromoketones afforded new (2E,4E)-5-aryl-2-(4-arylthiazol-2-yl)penta-2,4-dienenitriles. Direct bromination of the latter by the action of bromine in DMF proceeded regiospecifically at the C5 position of the thiazole ring without affecting the diene system and leads to the formation of new series of (2E,4E)-5-aryl-2-(5-bromo-4-arylthiazol-2-yl)penta-2,4-dienenitriles. [ABSTRACT FROM AUTHOR]

New Eu3+ and Tb3+ complex compounds [Ln(H2O)2L2]Cl∙H2O were synthesized on the basis of coumarin-3-carboxylic acid and its derivatives. Composition and structure of the ligands and the complex compounds were confirmed by NMR and IR spectroscopy, thermogravimetry, and complexometric titration. Europium(III) coordination compounds with coumarin-3-carboxylic and 6-nitrocoumarin-3-carboxylic acids show effective luminescence. [ABSTRACT FROM AUTHOR]

Bromination of (2E)-3-aryl(hetaryl)-2-[4-aryl(hetaryl)-1,3-thiazol-2-yl]acrylonitriles proceeds regioselectively at the C5 atom of the thiazole ring with the formation of new (2E)-3-aryl(hetaryl)-2-[5-bromo-4-aryl(hetaryl)-1,3-thiazol-2-yl]acrylonitriles. The latter were alternatively obtained by the reaction of aldehydes, cyanothioacetamide, α-bromoketones and bromine in the presence of triethylamine in DMF. Structure of the key compounds was confirmed using 2D NMR spectroscopy and single crystal X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

[Cu(L)2] (1), [Co(L)2] (2), [Ni(L)2]·H2O (3) complexes where L is 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dionate are synthesized. Single crystals of complexes 1-3 are obtained. According to X-ray crystallographic data, in the Co and Ni complexes, a coordination polyhedron N2O4 is a distorted octahedron, and in the Cu complex, N2O2 is a distorted square. L is a tridentate ligand coordinated by oxygen atoms of carbonyl and methoxy groups as well as the nitrogen atom of the amide group. The cytotoxic properties of 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dione and respective complexes are studied on the Hep2 cell line (human laryngeal carcinoma). The compounds are shown to not exhibit cytotoxic properties in the studied concentration range (1-50 μM). Antibacterial, protistocidal, and fungistatic properties of HL, its structural analogue 2-anilinomethylidene-5,5-dimethylcyclohexane-1,3-dione (HL1), and complexes on their base are also studied. The antibacterial activity of HL and [Co(L1)2(C2H5OH)2] against S. aureus, of HL1 and [Co(L)2] against E. coli is revealed within 25-30% of the activity of reference drugs (ciprofloxacin, furazolidone). The [Ni(L1)2(C2H5OH)2] complex is found to have a pronounced protistocidal activity. Furthermore, the behavior of the [Ni(L)2]·H2O complex in phosphate buffered saline is analyzed at storage times t = 0 h, 24 h, 48 h and also in an aqueous solution at different pH values. [ABSTRACT FROM AUTHOR]

The reaction of cyanothioacetamide with aromatic aldehydes and 1,3-dicarbonyl compounds followed by aminomethylation or S-alkylation gave a series of heterocyclic derivatives with a 1,2,3,4-tetrahydropyridine or 1,4,5,6,7,8-hexahydroquinoline fragment. The resulting compounds were tested for analgesic activity in vivo. Some of the prepared compounds showed an antinociceptive effect superior to that of ketorolac in dynamics. [ABSTRACT FROM AUTHOR]

1,6-Diamino-2-oxo-1,2,3,4-tetrahydropyridine-3,5-dicarbonitriles under the action of primary aliphatic amines and an excess of 37% formalin in ethanol were converted into 2,3,8,9-tetrahydro-6,10-methano[1,2,4]triazolo[1,5-a][1,5]diazocine-6,10(7H)-dicarbonitrile derivatives. At the same time, the Mannich reaction in the case of 1,6-diamino-4-aryl-2-oxo-1,2-dihydropyridine-3,5-dicarbonitriles proceeds ambiguously, and, depending on the conditions, gives either N-ethoxymethylation products or 1,2,4-triazolo[1,5-a]pyridine derivatives. In silico predictive analysis of the biological activity of new compounds was carried out. [ABSTRACT FROM AUTHOR]

The sequential reaction of furfural with cyclic secondary amines and further with benzaldehyde and cyanoacetates affords new 2,4-dicyano-8-(R2N)-6-oxo-3-phenylbicyclo[3.2.1]-octane-2,4-dicarboxylates as rac-(1R,2R,3R,4S,5S,8R)-diastereomers. The structures of the reaction products were determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

The recent data (2007–2018) on the synthesis of thieno[2,3-b]pyridines are summarized and systematized. [ABSTRACT FROM AUTHOR]

Hydroxymethylation of (E)-3-aryl-2-cyanoprop-2-enethioamides with an aqueous alcoholic solution of formaldehyde has afforded (E)-3-aryl-N-(hydroxymethyl)-2-cyanoprop-2-enethioamides. The predictive analysis of the biological activity of the obtained compounds in silico has been carried out. [ABSTRACT FROM AUTHOR]