Some reactions of nitropyrroles associated with the mobility of the N-H bond

Summary The salt formation, methylation, and cyanoethylation of nitropyrroles unsubstituted on the nitrogen were studied, and it was shown that the readiness with which these reactions occur depends on the acid character of the nitropyrrole.     

Synthesis and Spin State of the Cobalt(II) Complexes with Substituted 2,6-Bis(pyrazol-3-yl)pyridine Ligands

Russian Journal of Coordination Chemistry - The direct template reactions afford the cobalt(II) complexes (I–III) with the hydroxy- and acetyl-substituted 2,6-bis(pyrazol-3-yl)pyridine...     

Kinetics of enzymatic reactions in the production of fish protein hydrolysates

The kinetic laws of enzyme hydrolysis of waste products (heads, fins, bones, and muscle tissue) of the Atlantic cod Gadus morhua have been investigated. An enzyme specimen hepatopancreatine was used for the hydrolysis reaction (proteolysis). A kinetic model describing the mechanism of enzyme hydrolysis of fish proteins as a second-order reaction was developed. The proteolysis model was based on the existence of easily hydrolysed and hydrolysis-resistant protein fractions. Autolysis of the enzyme was also taken into consideration. In the context of the developed kinetic model, the second-order rate constants of the intermediate stages of proteolysis were calculated.     

Regio- and diastereoselectivity of the cycloaddition of nitrones with N-propadienylindole and pyrroles

The 1,3-dipolar cycloaddition of nitrones to N-propadienyl indoles and pyrroles proceeds predominantly via the C1-C2 bond to form 4-methyleneisoxazolidines. In the case of aldonitrones, the cis-isomers are predominantly formed.     

Magnetic and luminescent properties of copper-deficient Cu1–x(In0.7Ga0.3)Se2 (0 < x ⩽ 0.32) solid solutions with chalcopyrite structure

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Equivalent criterion of Haar and Franklin systems in symmetric spaces

In the present article it is proved that if the Haar and Franklin systems are equivalent in a separable symmetric space E, the following condition holds: 0<_EE<1, (1) where _E and _E are the Boyd indices of the space E. It is already known that if condition (1) is fulfilled, it follows that the Haar and Franklin systems are equivalent in the space E. Thereby, this estabishes that condition (1) is necessary and sufficient for the equivalence of the Haar and Franklin systems in E.In proving the assertion a number of interesting constructions involving Haar and Franklin polynomials are presented and upper and lower bounds on the Franklin functions applied.Translated from Matematicheskie Zametki, Vol. 52, No. 3, pp. 96–101, September, 1992.     

On some problems of interpolation by ℒ-splines

_n (D) — ,s — _n (D), _v (v=1, 2, ...,s/2) — . _m={0x ₀<x ₁<...<x _2m–1<2,x _2m =x ₀+2} , x _j +1–x _j <(4s max _v )^–1,j=0, 1, ..., 2m –1, ( ) 2- - _n,m 2m , _m . , L _q - (1q) W ( _n )={f ₂ :f ^(n–1)AC ₂ , _n (D)f 1} 2- - (s _n f), _m . , - - _n,m .

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The author expresses his gratitude to Yu. N. Subbotin for a useful discussion on the results of this paper.