Utility of N‐[4‐(N‐Substituted Sulfamoyl)Phenyl] Cyanothioformamides in the Synthesis of Heterocyclic Compounds

The novel cyanothioformamides 2a‐d were prepared by treatment of isothiocyanatosulfonamides 1a‐d with potassium cyanide at room temperature. Cyclocondensation of compounds 2b,c with phenyl isocyanate as electrophile furnished the corresponding imidazolidines 3a,b . The reactivity of compound 3a towards some nitrogen nucleophiles was investigated. Thus, the thiosemicarbazone 4 and imidazo[4,5‐b]quinoxaline 6 were synthesized by condensation of compound 3a with thiosemicarbazide and o‐phenylenediamine, respectively. Treatment of 3a with hydrochloric acid afforded compound 7 . Our investigation was extended to include the reactivity of cyanothioformamide 2 towards o‐aminophenol, anthranilic acid, and o‐phenylenediamine and yielded the corresponding heterocycles 9 , 11 and 13 derivatives, respectively. Structures of the synthesized compounds were established by their elemental analysis and spectral data.     

Electrophoretic and amino acid compositions of the proteins of maize lines differing in the anthocyan coloration of the seeds

The electrophoretic and amino acid compositions of the proteins of lines of maize differing in the anthocyan coloration of their seeds have been investigated. The molecular masses of the quantitatively main components ranged from 11 to 42 kDa for the albumins and from 15 to 81 kDa for the globulins. Differences between the lines were observed in the levels of components with molecular masses of from 11 to 31 kDa. The amino acid compositions of the zeins of the lines studied were characterized by high levels of leucine, glutamic acid, aspartic acid, alanine and serine, and those of the other groups of proteins by high levels of arginine, glutamic acid, and glycine.Institute of Genetics, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 64 22 30. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 871–873, November–December, 1997.     

Synthesis of lepidine and its derivatives from aromatic amines and quaternary salts of Mannich bases

A quaternary salt of 4-(diethylamino)butan-2-one, methyldiethyl-3-ketobutylammonium methyl sulfate, is used as an alkylating agent to synthesize lepidine and 1-phenyllepidine salts. The method gives good yields, under mild conditions, of lepidine and 1-phenyllepidine perchlorate. An intermediate product is isolated, and a reaction mechanism suggested.     

The energies of dissociation of the N—O bonds in pyridine 1-oxide derivatives

The enthalpies of combustion of some pyridine derivatives in the solid state have been measured by precision bomb calorimetry, and their enthalpies of formation have been calculated. The enthalpies of sublimation of these compounds have been determined from the experimental temperature dependences of saturated vapor pressure using the Clausius-Clapeyron equation. The enthalpies of combustion, formation, and sublimation are the following (kJ mol^–1): -3360.9±2.1, -0.5±2.1, and 79.1±1.3, respectively, for 4-methylpyridine 1-oxide; -2551.0±1.7, 11.7±1.7, and 89.1±2.5, respectively, for 4-nitropyridine 1-oxide;-2355.6±1.3, 102.1±1.3, and 106.3±2.9 for 2,4,6-trinitropyridine 1-oxide; and -2287.6±1.3, 34.3±1.3, and 101.7±2.9 for 2,4,6-trinitropyridine. The enthalpies of formation in the solid state and the enthalpies of sublimation of pyridine derivatives obtained together with the literature data allowed the energies of dissociation of the donor-acceptor N—O bonds in pyridine 1-oxides to be calculated.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 660–662, April, 1995.     

Periodic Gibbs measures for the three-state SOS model on a Cayley tree with a translation-invariant external field

Theoretical and Mathematical Physics - We consider a three-state solid-on-solid (SOS) model on a Cayley tree in the presence of an external field. We show that periodic Gibbs measures are either...     

On a Boundary Value Problem for a System of Differential–Difference Equations of Retarded Type

Differential Equations - We consider a control system described by a system of differential equations of retarded type with variable matrix coefficients and several delays. The relationship between...     

Boundary-value problem for the two-dimensional stationary heisenberg magnet with nontrivial background. II

The investigation of the boundary-value problem on a half-plane for the two-dimensional stationary Heisenberg magnet is continued. The asymptotic behavior of N-soliton solutions is discussed. The asymptotic contribution of the continuous spectrum is calculated. The gauge equivalence of the boundary-value problems for the models of a magnet and the elliptic equation represented by the sinh—Gordon equation is considered.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 104, No. 3, pp. 513–529, September, 1995.     

Studies on the liquid-liquid extraction and precipitate flotation of the second kind of Co(II) using 8-hydroxy quinoline

Catalysis of mixed oxide LaMnO₃ was studied for the decomposition of hydrogen peroxide (H₂O₂). The catalyst was -irradiated in open petri dishes, vacuum, dry oxygen and moist oxygen. LaMnO₃ irradiated in moist oxygen showed highest catalytic activity. X-ray photoelectron spectroscopic (XPS) studies were carried out to investigate the surface modifications occurred during -irradiaiton of LaMnO₃. No significant change in the surface was noticed in LaMnO₃ irradiated in vacuum and dry oxygen. However, LaMnO₃ irradiated in moist oxygen and in open petri dishes showed the reduction of transition metal (MN³⁺ to Mn²⁺) which in turn leads to the formation of chemisorbed superoxide ions (O ₂ ^– ) and surface carbonate species (CO ₃ ^2– ). The latter processes decreases the electrical conductivity by trapping the charge carriers. The hydrated electron generated by the radiolysis of moisture reduces the transition metal. A qualitative molecular orbital model has been proposed for the chemisorption of O ₂ ^– on the reduced transition metal centers (Mn²⁺).     

On low-degree p mode rotational splitting

This paper is devoted to the measurement of low-degree p mode rotational splitting, which is one of the most urgent problems in helioseismology. The last three years witnessed considerable progress in this field. It can be stated with confidence that the angular velocity of solar core rotation exceeds only marginally or even does not exceed the rotation velocity of the Sun envelope, except for an area of radius 0.1R in the deep interior of the core. Further progress in this avenue encounters a variety of serious difficulties for lack of reliable data on g modes. These difficulties are due to the physical nature of the p modes themselves and the imperfection of the analytical techniques.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 10, pp. 1218–1221, October, 1996.     

Linear operators generated by stochastic processes

Let X_t(0 t < ) be a homogeneous stochastically continuous stochastic process with independent increments; (, A, P) be the corresponding probability space; p, q1 be fixed numbers. Necessary and sufficient conditions are found for a stochastic integral defined on finite-valued functions to be extendable to a bounded operator from L_p (0, ) to L_q() (p q).Translated from Teoriya Sluchainykh Protsessov, No. 16, pp. 7–13, 1988.