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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.

The spectral characteristics of dithiomalondianilide ( N , N ′-diphenyldithiomalonodiamide) were studied, and the dissociation constant was determined by potentiometric titration. Quantum-chemical methods at the B3LYP-D3BJ/6-311+G (2d,p) level were used to calculate the molecular geometry and vibrational spectra of the most stable tautomeric forms of dithiomalondianilide. The bioavailability parameters were calculated, and possible protein targets were predicted by the protein ligand docking method.

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This paper is devoted to obtaining and investigating the stability of silver and palladium sols in N,N-dimethylformamide medium. Due to the unique properties exhibited by metals in the nanosized state, metallic nanoparticles are gaining increasing importance in various fields of application, science and technology. This makes the task of obtaining stable metal sols extremely urgent. The synthesis of aggregate-resistant organosols of metals is associated with a number of problems, since the metal sols obtained in organic media are much less stable than hydrosols. For this reason, there arises the challenge of choosing an appropriate stabilizer. In this study, the stabilizer was branched polyester Laprol 5003. A distinctive feature of the synthesis of silver sols was the absence of a special reducing agent, since N,N-dimethylformamide, used as a solvent, recovers silver cations  itself. As a result, stable sols of silver and palladium have been obtained in N,N-dimethylformamide medium. Sodium borohydride was used as the reducing agent for the synthesis of palladium nanoparticles. Spectral studies of the resulting sols were carried out. The silver and palladium nanoparticles were sized up by scanning electron microscopy. The procedure has shown that the average size of the silver particles formed in the N,N-dimethylformamide medium is 4 ± 2 nm, which is substantially smaller than the particles obtained in isopropanol medium by the borohydride method.  The silver sols aggregation in dimethylformamide under the action of potassium thiocyanate was studied via optical absorption spectroscopy. It has been found that the stability of the silver sol in dimethylformamide to the electrolyte is higher than that of the sol obtained in isopropanol. It has also been detected that several absorption bands are present in the optical spectrum of the palladium sol in dimethylformamide. The effect of the stabilizing polyester concentration on the stability of silver and palladium sols in N,N-dimethylformamide was studied. The result is that when the concentration of Laprol 5003 exceeds some quantity, a sharp increase in the aggregation time of sols is observed, which indicates a significant increase in their stability.

The main physical-chemical characteristics of ceramic high-porosity block-cellular catalysts coated with a palladium active layer in the process of oxidation of hydrogen under different experimental conditions are presented. It is concluded on the basis of the data obtained on the energy of activation and catalytic activity that in comparison with imported granular catalysts they hold promise for use in the catalytic oxidation of hydrogen isotopes.Ceramic high-porosity block-cellular catalysts of the oxidation of hydrogen isotopes with a platinum active layer, deposited by permeation from a solution of platinum-chlorine-hydrogen acid followed by reduction, have exhibited high efficiency [1] and a number of advantages over the commercial granular platinum catalyst JM (Great Britain) [2] in the process of hydrogen oxidation, which are mainly due to the characteristic arch-labyrinthine structure and strength of the ceramic framework [3,4].The aim of obtaining palladium catalysts, which are similar in terms of the structure and physical-chemical characteristics, for the oxidation of hydrogen isotopes on the basis of high-porosity ceramic cellular materials (HPCM), aside from lowering their cost of production as a result of the replacement of platinum by palladium, was to check the efficacy of a palladium active layer deposited by means of chemical precipitation [5].The characteristics of the samples of ceramic high-porosity block-cellular catalysts, containing a palladium active layer and metallic palladium in amounts no more than 1% (mass fraction) of the mass of the ceramic carrier, which are fabricated for performing tests in a catalytic hydrogen-oxidation reactor are presented in Table 1. This content of palladium in the experimental samples corresponds to the platinum content in the commercial granular catalyst JM (Johnson Matthey, Great Britain), also taken for comparison.Electronic photomicrographs of samples with a deposited palladium coating are presented in Fig. 1. They attest to the formation of a compact palladium coating on the surface of the cellular-mesh ceramic framework, where the coating consists of rough aggregates with an extended outer surface and an appreciable number of micropores. The cellular struc-