ChemInform Abstract: γ-Carbolines and Their Hydrogenated Derivatives. Part 2. Hydrogenated Derivatives of γ-Carbolines: Methods of Synthesis

Methods of synthesis of new prospective polyol components for obtaining of polyurethane foams of reduced combustibility using eco-friendly substrates have been presented. With this end in view, N,N′-bis(2-hydroxypropyl)urea was esterified with boric acid and next the hydrogenborate obtained was hydroxyalkylated by the excess of propylene carbonate. The influence of the way of esterification on the hydroxypropyl derivatives of borate substituted urea properties has been investigated. Esterification was run in the presence and in the absence of solvent. According to instrumental analysis, the characteristic of hydrogenborates obtained in both methods was found to be similar. The hydroxypropyl derivatives of borate substituted urea show similar spectral characteristics and thermal stabilities and differ slightly in molar masses, by-product contents, and physical properties, particularly viscosities. The properties of these derivatives were assessed paying special attention to their application as the polyol components of polyurethane foams. Hydroxypropyl urea derivatives, modified by boric acid, show changes in physical properties with temperature, similarly to typical polyols used for obtaining of polyurethane foams.

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Synthesis, physico-chemical properties of 3-thio and 3-thio -4-amino derivatives of 1,2,4-triazole

Farmatsevtychnyi zhurnal ◽

10.32352/0367-3057.2.15.01 ◽

2019 ◽

pp. 28-44

Author(s):

V. V. Parchenko

Keyword(s):

Chemical Properties ◽

Biological Properties ◽

Modern Medicine ◽

Toxic Substances ◽

Triazole Derivatives ◽

Synthetic Drugs ◽

Physico Chemical ◽

Methods Of Synthesis ◽

Amino Derivatives ◽

Derivatives Of

Modern medicine and pharmacy has at its disposal highly efficient synthetic drugs. Large extent of these drugs accounted for derivatives of 1,2,4-triazole. The purpose of the work was an attempt to summarize the literature in recent years related to the methods of synthesis and study of physico-chemical properties 3-thio- and 3-thio-4-amino derivatives of 1,2,4-triazole. Studies national scientists in recent years indicates prospects of the search in this direction, since this class of organic compounds is interest not only to scientists pharmaceutical, medical and veterinary field, but also among researchers of engineering, metallurgical and agricultural areas. 1,2,4-triazole derivatives are also widely used in practice for optical materials, photosensitizers are used as coloring agents, antioxidants, additives for fuels and oils, some of which are widely used as corrosion inhibitors for controlling various pests in agriculture. In addition, 1,2,4-triazole derivatives belong to the class low toxic or essentially non-toxic substances. The presence of a growing number of publications about methods of synthesis, reactions, physico-chemical and biological properties of 1,2,4-triazole, inspires scientists around the world search for perspective molecules of substituted 1,2,4-triazole. It should be noted that in spite of a sufficient amount of information about the derivatives of 1,2,4-triazole, some issues related to the generalization of data in the literature synthesis presented insufficient.

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Statistical properties of derived signal systems

Radiotekhnika ◽

10.30837/rt.2020.4.203.14 ◽

2020 ◽

pp. 141-147

Author(s):

A.A. Zamula ◽

I.D. Gorbenko ◽

Ho Tri Luc

Keyword(s):

Statistical Properties ◽

Random Sequences ◽

Signal Systems ◽

Discrete Signals ◽

Information Transformation ◽

Methods Of Synthesis ◽

Linear Signal ◽

Correlation Properties ◽

Derivatives Of ◽

Structural Ensemble

The search for effective methods of synthesis of discrete signals (sequences) that correspond to the potentially possible limiting characteristics of correlation functions and possess the necessary correlation, structural, ensemble properties remains an urgent problem. The authors have proposed a method for the synthesis of derivatives of signal systems, for which orthogonal signals are used as the initial ones, and nonlinear discrete complex cryptographic signals (CS) are used as generating signals. The synthesis of the latter ones is based on the use of random (pseudo-random) processes, including algorithms for cryptographic information transformation. Derivative signals synthesized in this way have improved (in comparison with linear signal classes) ensemble and correlation properties, while the statistical properties of such signal systems remain unexplored. The paper presents the results of testing derived signal systems using the tests defined in FIPS PUB 140 and NIST 800-22. Analysis of the results obtained allows us to assert that the statistical properties of this class of derived signals satisfy the requirements for pseudo-random sequences: unpredictability, irreversibility, randomness, independence of symbols, etc. In essence, such signals do not differ from random sequences. The use of the proposed class of derived signals will improve the performance of signal reception noise immunity, information security and secrecy of the ICS functioning.

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Boranes in Organic Chemistry 3. α-, β- and γ-Haloalkylboranes: The Perspective Vehicles for Organic Synthesis

Eurasian Chemico-Technological Journal ◽

10.18321/ectj288 ◽

2016 ◽

Vol 5 (2) ◽

pp. 83 ◽

Cited By ~ 1

Author(s):

V.M. Dembitsky ◽

G.A. Tolstikov ◽

M. Srebnik

Keyword(s):

Organic Chemistry ◽

Nucleophilic Substitution ◽

Organic Synthesis ◽

General Scheme ◽

Radical Addition ◽

Boronic Esters ◽

Methods Of Synthesis ◽

Boron Tribromide ◽

Derivatives Of ◽

Acid Esters

<p>The methods of synthesis of α− and β−haloalkylboranes, including chloration of alkylboronic acid esters, additive bromation and chloration of esters of vinyl- and alkenylboronic acids, addition of bromine to trivinylborazines have been considered. The reactions of radical addition of polyhaloidmethanes to vinylboranes, α− and β−unsaturated boronic esters, B-vinyl-B-arylboronic esters, B-trivinyl-B-triarylborazines were discussed. The hydroboration of acetylenic halogenides of dicycloalkylboranes, which led to halocontaining derivatives of dialkylvinylborane was separately considered. The examples of hydroboration of halogenides of allyl and vinyl types are presented. The reaction of dienic synthesis, which takes place between vinylchloroboranes or vinylboronic esters and tetra- or hexachlorocyclopentadienes has been discussed. The reaction of alkenes and allenes with boron tribromide was described. The Markovnikov and non-Markovnikov hydrobromation of boron vinylderivatives has been envisaged. The approaches to the synthesis of perfluoroalkylboranes on the base of hydroboration of perfluoroalkenes have been discussed. The methods of the synthesis of boronates, containing halogetaryl substituents, have been performed. The reactions of hydroboration of halogenides of allylic and propargylic types by 9-borabicyclononane have been shown. The regio- and stereoselectivity of the reaction has been discussed. The examples of the synthesis of boranes of the norbornene type were presented. The reaction of boroallylilation of allyl- and propargylhalogenides leading to the derivatives of 3-bora-bicyclo[3,3,1]-nonane has been discussed. Some directions of using of haloidalkylboranes in the synthesis have been discussed. The examples of nucleophilic substitution leading to oxyalkyl- and azidoalkylboranes have been presented. The route of obtaining of alcohols from α−haloidalkylboranes has been shown. The general scheme of synthesis of α−aminoboronic acids was perfomed. The general approach to the synthesis of allenes on the base of hydroboration products of propargyl halogenides has been discussed. The schemes of synthesis of 1,4-disubstituted-1,2,3-butatrienes are presented. The wide using reaction of introducing of vinylic group into substituent, bonding with boron atom in molecules of dialkylvinylboranes, was discussed. The reactions of new C-C bonds formation, based on the action of iodine on the alkylvinylboronates leading to 1,3-dienes and alkylidencyclanes have been shown. Τhe route of the synthesis of cyclopropanes from β−haloidalkylboranes has been discussed.</p>

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Synthesis of 1-phenylindoles derivatives

Butlerov Communications ◽

10.37952/roi-jbc-01/19-58-4-53 ◽

2019 ◽

Vol 58 (4) ◽

pp. 53-57

Author(s):

Alexander V. Syromolotov ◽

◽

Alexander A. Kimyashov ◽

Diana R. Khafizova ◽

◽

...

Keyword(s):

Copper Chloride ◽

Aryl Halide ◽

Physiological Activity ◽

Reaction Conditions ◽

Structural Formulas ◽

Methods Of Synthesis ◽

Ancient Times ◽

Physical And Chemical ◽

Derivatives Of ◽

Physiological Value

The growing needs of medicine and pharmacology induce synthetic organic chemistry to constantly be in the process of modernizing existing methods of synthesis and developing new ones. Since ancient times, the high physiological activity of indole derivatives has been widely known. Indole is a heterocyclic condensed aromatic compound that is part of the molecules of a multitude of compounds with biochemical and physiological value. A large number of drugs of the indole group obtained synthetically are derivatives of arylindols. One of the most common methods of obtaining arylindoles is the use of Ulman reaction conditions. However, this technique involves the use of high temperatures and a large amount of aryl halide to obtain optimal yields. Some classical methods suggest the use of palladium compounds as a catalyst, which are highly prices and require inert conditions, which limits their uses in the syntheses and reduces the overall synthetic attraction. In order to mitigate the conditions of the Ulman reaction and increase the reaction yields, methods have been proposed for the synthesis of 1-phenylindole derivatives based on the introduction of phenyldiodide by arylating the nitrogen atom in position 1 of the 5-methoxyindole indole ring in the presence of monovalent copper chloride using phenanthroline and anthracene as ligands, followed by heteroarylation the compounds obtained quinoline and isoquinoline in the presence of benzoyl chloride and 2-bromo-3-methylbutanoyl chloride. The physical and chemical characteristics of the compounds obtained were determined. Installed using 1H NMR spectroscopy and elemental analysis of the structure of the obtained derivatives are in good agreement with the proposed structural formulas. According to a review of literature data, the obtained structures can be supposedly used to research their physiological activity.

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