Synthesis of N,7-diaryl-5-methyl-4,7-dihydro-1,2,4-triazolo[1,5-a]-pyrimidine-6-carboxamides

Reaction of N-arylamides of acetoacetic acid with aromatic aldehyde and 3-amino-1,2,4-triazole derivatives has resulted in N,7-diaryl-5-methyl-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-6-carboxamides.     

Three-component synthesis of 6-aryl-4-methyl-2-oxo-1,2,3,6-tetrahydropyrimidine-5-(N-aryl)carboxamides

A three-component synthesis using acetoacetanilides and a mixture of an aromatic aldehyde and urea yields 6-aryl-4-methyl-2-oxo-1,2,3,6-tetrahydropyrimidine-5-(N-aryl)carboxamides.     

Material parameters for angular ranges in biisotropic media

A comparison was carried out on systems of material equations which have been proposed to describe regular biisotropic media. In order to satisfy the edge conditions over a range of angles, limits are imposed on the values of the material parameters for a lossless biisotropic medium. Ranges of undefined values arise for the medium parameters with simple angular structures having ideally conducting boundaries.V. D. Kuznetsov Physico-Technical Institute, Tomsk State University, Siberia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 51–57, April, 1995.     

Synthesis of <Emphasis Type="Italic">N</Emphasis>-Aryl- and <Emphasis Type="Italic">N,N</Emphasis>-diethyl-2-methyl-3-phenyl-4-sulfanylidene-3,4,5,6-tetrahydro-2<Emphasis Type="Italic">H</Emphasis>-2,6-methano-1,3,5-benzoxadiazocine-11-carboxamides

N-Aryl- and N,N-diethyl-3-oxobutanamides reacted with salicylaldehyde and N-phenylthiourea in ethanol in the presence of sodium hydrogen sulfate as catalyst to give the corresponding N-substituted 2-methyl-3-phenyl-4-sulfanylidene-3,4,5,6-tetrahydro-2H-2,6-methano-1,3,5-benzoxadiazocine-11-carboxamides.     

On teaching sets for 2-threshold functions of two variables

We consider k-threshold functions of n variables, i.e. the functions representable as the conjunction of k threshold functions. For n = 2, k = 2, we give upper bounds for the cardinality of the minimal teaching set depending on the various properties of the function.     

Interrelationships of the structures and antioxidant activities of some flavonoids from the plants of Central Asia

A study has been made of the influence 27 flavonoids on the processes involved in the peroxide oxidation of lipids. The interrelationship between the chemical structures of isoflavones, flavones, flavanones, and flavonols and their antioxidant activities is discussed.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 350–356, May–June, 1996. Original article submitted November 21, 1994.     

New synthesis of ethyl 6-amino-4-aryl-5-cyano-1,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates

Ethyl 6-amino-4-aryl-5-cyano-1,4-dihydropyrano[2,3-c]pyrazol-3-carboxylates were synthesized by a reaction of diethyloxalacetate sodium salt with aromatic aldehyde, hydrazine hydrate, and malononitrile in the presence of acetic acid.     

Synthesis,Structure, and Antibacterial Activity of Alkyl 6-Aroyl-7-aryl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-5-carboxylates

Russian Journal of General Chemistry - A series of new alkyl 6-aroyl-7-aryl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-5-carboxylates was obtained through the three-component reaction of alkyl esters...     

Synthesis and antimicrobial activity of <Emphasis Type="Italic">N</Emphasis>,6-diaryl-4-methyl-2-thioxo-1,2,3,6-tetrahydropyrimidine-5-carboxamides

Three-component reactions of acetoacetic acid N-arylamides, aromatic aldehydes, and thiourea afforded N,6-diaryl-4-methyl-2-thioxo-1,2,3,6-tetrahydropyrimidine-5-carboxamides. Structure and antimicrobial activity of the compounds obtained were examined.     

Field generated by an anisotropic conducting plane in a half-space with chiral properties

This article inaugurates theoretical studies on a new class of composite structures that are a combination of anisotropically conducting surfaces and media possessing chiral properties. To test the mathematics, we solved the simplest model of the problem in which an in-phase electric current filament excites a plane formed by a layer of straight conductors at the interface of two isotropic media, one of which is chiral. The solution is given as a Fourier integral. As shown by analysis, one retarded wave of a discrete spectrum and three waves of a continuous spectrum are excited in the given structure. The first one exists only because of the anisotropically conducting plane and does not exist without it, while the latter three are associated with plane waves of corresponding homogeneous media, magnetodielectric and chiral.V. D. Kuznetsov Siberian Physicotechnical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 34–38, September, 1994.