Pyrimidine derivatives. 58. A new method for synthesizing 7-aminopyrrolo[2,3-d]-pyrimidine derivatives

A number of aldimines of 7-aminopyrrolo[2,3-d]pyrimidine have been synthesized by the action of bromine on hydrazones of 5-allyl-4-hydrazinopyridine. The structures of the compounds obtained were confirmed by IR spectroscopy and mass spectrometry.For Communication 57, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 678–681, May, 1985.     

Production of Magnetic Supports Coated with Silica Layer from Dispersed Cobalt and Zinc-Nickel Ferrites

The possibility of obtaining dispersed powders of cobalt and zinc-nickel ferrites with particle size of 1-4 m by thermal treatment of the corresponding oxalates was analyzed. Changes in porous characteristics of the ferrites obtained in their thermal treatment were studied.     

ESR studies of free radicals formed during hydrogen and methane oxidation in contact with chalcopyrite

ESR studies have revealed that in the complex conjugated transformations of chalcopyrite under the effect of gasphase chain oxidation of methane and hydrogen, free radicals are formed. These radicals are sulfur-containing paramagnetic particles.

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Chromatographic Properties of Silica Gel Packing Materials as Influenced by Polymeric Coating

Some chromatographic properties of microspheric silica gels coated with copolymer of polystyrene, p-divinylbenzene, and allyl alcohol were studied. The measurements were performed by reverse-phase high-performance liquid chromatography using modified C₈ and C_{1 8} phases with secondary silanization with trimethylchlorosilane.     

Synthesis and intramolecular recyclization of 2,2-dialkyl-6-chloro-4-hydroxymethyl-benzo[<Emphasis Type="Italic">f</Emphasis>]isoindolinium salts

The intramolecular cyclization of dialkyl(2-butynyl-4-hydroxy)[3-(p-chlorophenyl)propargyl]ammonium chlorides, catalyzed by aqueous KOH, was realized. It was shown that the obtained products — 2,2-dialkyl-6-chloro-4-hydroxymethylbenzo[f]isoindolinium chlorides — readily undergo recyclization under the action of a twofold molar amount of KOH in aqueous solution with heating with the formation of 4-dialkylaminomethyl-8-chloro-1,3-dihydronaphtho[1,2-c]furans. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 834–840, June, 2007.     

The completeness of systems of functions of the Mittag-Leffler type for weighted uniform approximation in a complex domain

For a givenρ(1/2 <ρ < + ∞) let us set L _ρ = {z: |arg z| = π/(2ρ)} and assume that a real valued measurable function ?(t) such that ?(t) ≥ 1(t ∈ L _ρ ) and \(\mathop {\lim }\limits_{|t| \to + \infty } \varphi (t) = + \infty (t \in L_\rho )\) is defined on L _ρ . Let C _? (L _ρ ) denote the space of continuous functionsf(t) on L _ρ such that \(\lim \tfrac{{f(t)}}{{\varphi (t)}} = 0\) , where the norm of an elementf is defined as: \(\parallel f\parallel = \mathop {\sup }\limits_{t \in L_\rho } \tfrac{{|f(t)|}}{{\varphi (t)}}\) . In this note we pose the question about the completeness of the system of functions of the Mittag-Leffler type {Eρ(ut; μ)} (μ ≥ 1, 0 ≤ u ≤a) or, what is the same thing, of the system of functions \(p(t) = \int_0^a {E_\rho (ut;\mu )d\sigma (u)} \) in C _? (L _ρ ). The following theorem is proved: The system of functions of the Mittag-Leffler type is complete in C _? (L _ρ ) if and only if sup |p(z)| ≡ +∞, z ∈ L _ρ , where the supremum is taken over the set of functions p(t) such that ∥p(t) (t + 1)^?1 ∥ ≤ 1.     

Four-Photon Adiabatic Excitation of Rydberg States

Propagation of four laser pulses in the five-level ladder system in the case of arbitrary intensities and the different strengths of oscillators is investigated, when one of the eigenstates of the interaction Hamiltonian is formed in the whole volume of the medium. Taking into account the first non-adiabatic correction, the equations of propagation are obtained. An analytical solution of these equations is obtained. The conditions for an effective excitation of the fifth level in the whole volume of medium and the limitations on the interaction parameters are obtained as well.     

Comparison of the Reactivities of Tyrosine–Proline-Based Dipeptides toward Acylation with Nitrophenyl Benzoates

Russian Journal of Organic Chemistry - The reactivities of the L-Tyr–L-Pro dipeptide and its analog with a hydroxymethyl group instead of carboxy group in the proline moiety were compared by...