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2- and 4-(Arylmethylideneamino)phenols react with Reformatsky reagent, obtained from methyl 1-bromocyclohexanecarboxylate and zinc, to form 3-aryl-2-[2-(or 4-)hydroxyphenyl]-2-azaspiro[3.5]nonan-1-ones. The reaction involves the initial addition of the organozinc reagent across the C=N double bond of the Schiff base and the subsequent intramolecular cyclization of the adduct via the nucleophilic attack of the nitrogen atom on the ester carbonyl carbon atom. The structures of the products were confirmed by X-ray diffraction analysis.

Depending on the ring size in the Reformatsky reagent and the nature of substituents in arylmethylidene fragment, the reactions of Reformatsky reagents obtained from methyl esters of 1-bromocycloalkanecarboxylic acids and zinc with N′-(arylmethylidene)-2-oxo-2H-chromene-3-carbohydrazides afforded methyl 1-{3-[2-(arylmethylidene)hydrazinylcarbonyl]-2-oxochroman-4-yl}cycloalkanecarboxylates or methyl 1-{3-[(3-aryl-1-oxo-2-azaspiro[3.5]nonan-2-yl)carbamoyl]-2-oxochroman-4-yl}cyclohexanecarboxylates. The resulting compounds exhibit antinociceptive activity.

1-Aryl-3-(2-hydroxy-5-R-phenyl)prop-2-en-1-ones reacted with the Reformatsky reagent derived from methyl 1-bromocyclohexanecarboxylate to give 4-(2-aryl-2-oxoethyl)-6-R-2H,4H-spiro[[1]benzopyran-3,1′-cyclohexan]-2-ones. The products are formed as a result of intramolecular cyclization of the adduct of the organozinc reagent and substituted chalcone via nucleophilic attack of the phenoxide oxygen atom on the ester carbonyl carbon atom. No cyclization products resulting from attack of the enolate oxygen atom on the ester carbonyl carbon atom were detected.

New substituted pyrazolo[3,4-d]pyrimidin-4-ones have been synthesized as a result of a series of transformations including hydrolysis of ethyl 5-amino-1H-pyrazole-4-carboxylates, cyclization of the carboxylic acids thus obtained to pyrazolo[3,4-d][1,3]oxazin-4(1H)-ones, and treatment of the latter with substituted anilines. The final pyrazolo[3,4-d]pyrimidin-4-one derivatives can also be synthesized from 5-(arylamido)-1H-pyrazole-4-carboxylic acids in the presence of a catalytic amount of anhydrous zinc(II) chloride.

The electron-spin-resonance (ESR) spectra of SrTiO3:Mn single crystals have been investigated. Results unambiguously indicate that the impurity center formed by an Mn2+ ion has a dynamic nature. In the high temperature range (T > 100 K), ESR spectra of Mn2+ ions reveal cubic symmetry; the spectrum is found to broaden significantly with a decrease in temperature. Upon cooling to T < 10 K, low-symmetry centers of Mn2+ ions with a strong orientational dependence emerge in the spectra. Temperature evolution of the ESR spectrum can be described within the model of a dynamic off-center Mn2+ ion substituting for the Sr2+ ion, with a transition to the static regime at low temperatures with an average localization energy of ∼2.4 ± 0.4 meV for Mn2+ centers due to random deformations.

We study paramagnetic resonance linewidth in a series of CaWO4 and CaMoO4 crystals with different concentrations of neodymium ions (0.0031–0.81 at %). Experimental data are interpreted in the framework of the statistical theory of line broadening by charged point defects. In our calculations, three different contributions are singled out: arising from the local electric fields, electric field gradients and magnetic fields of the nearby point defects. The interaction parameters are determined from the spectroscopic data available for Nd:CaWO4 crystal. Direct calculations of the linewidth are performed for different crystal orientations with respect to external magnetic field. We conclude that major contribution to the broadening comes from the interactions with random electric fields produced by neodymium and charge compensator ions.

The structure of a two-phase stream in a regular grainy bed of a separator was analyzed. A two-phase emulsion stream in a grainy bed transforms into a stream of two mutually permeable continuous phases with a highly developed and nondegenerate (i.e., not varying noticeably with time) phase boundary surface, which creates favorable conditions both for induced coalescence of emulsion contaminations and for mass exchange between the streams. High retaining power of a grainy bed toward minor stream and the corresponding differences in the flow velocities give rise to a braking effect for impurities adsorbed on the phase boundary, which allows the use of the separator for removing solid phase particles from the product stream. The possibility of removing carbon black particles from a stream simulating a spent nuclear fuel solution was demonstrated.

The study of the ability of Lactobacillus plantarum 8P-A3 to synthesize nitric oxide (NO) showed that this strain lacks nitrite reductase. However, analysis by the EPR method revealed the presence of nitric oxide synthase activity in this strain. Like mammalian nitric oxide synthase, lactobacillar NO synthase is involved in the formation of nitric oxide from L-arginine. L. plantarum 8P-A3 does not produce NO in the denitrification process. The regulatory role of NO in symbiotic bacteria is emphasixed.

It was pointed out in some works that asymmetry of an electron paramagnetic resonance (EPR) line is generally caused by both the electrical conduction and the nondiagonal elements of the dynamic susceptibility of a magnetic subsystem. Direct measurements of the temperature dependences of the conductivity and the EPR line shape in a La0.70Ca0.25Ba0.05MnO3 sample showed that the conduction makes the predominant contribution to the EPR line asymmetry.