Yu. M. Volovenko

Synthesis of condensed pyrrolo[b]pyrazines

Reaction of 2,3-dichloro-5,6-dicyanopyrazine with α-azahetarylacetonitriles gives α-(3-chloro-5,6-dicyanopyrazin-2-yl)-α-(2-azahetaryl)acetonitriles. Subsequent heating in pyridine causes an intramolecular cyclization to yield condensed pyrrolo[b]pyrazines.

4-Oxo-3,4-dihydroquinazolinyl- and Benzimidazolylacetonitriles in Annelation Reactions of a Haloquinoline Ring

The interaction of 4-oxo-3,4-dihydroquinazolinyl- and benzimidazolylacetonitriles with 2,6-dihalobenzaldehydes leads to 3-(2,6-dihalophenyl)-2-(4-oxo-3,4-dihydro-2-quinazolinyl)acrylonitriles and 2-(1H-benzo[d]imidazol-2-yl)-3-(2,6-dihalophenyl)acrylonitriles respectively. As a result of intramolecular cyclization of these nitriles 4-halo-12-oxo-12H-quino[2,1-b]quinazoline-6-carbonitriles and 4-halobenzo[4,5]imidazo[1,2-a]quinoline-6-carbonitriles respectively are formed.

Synthesis and Properties of 2-Amino-6-nitroindoles

A new method is proposed for the synthesis of 2-amino-6-nitroindoles, based on the reaction of 2-haloanilines and substituted acetonitriles. The reaction of 2-amino-6-nitroindoles with β-dicarbonyl compounds was studied.

Interaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutane nitriles with esters of aromatic amino acids

The reaction of 2-(2-azahetaryl)-3-oxo-4-chlorobutane nitriles with esters of aromatic acids was studied. A series of 1H,4H-3-(2-azahetaryl)pyrrolo[1,2-a] quinazoline-2,5-diones and 1-aryl-2-amino-3-(2-azahetaryl)-4-(5H)-oxopyrroles was obtained. The reaction of the latter with hydrazine and acetic anhydride was investigated.

SYNTHESIS OF 1-R-2-AMINO-3-2-(BENZ)AZOLYL-4(5H)-KETOPYRROLES

A study has been made of the interaction of 2-[2-(benz)azolyl]3-keto-4-chlorobutanenitriles with primary aliphatic amines. This is a convenient method for the synthesis of 2-amino-3-[2-(benz)azolyl]-4(5H)-ketopyrroles.

Use of azolium ylides in the synthesis of con-densed heterocyclic systems from 2-quinox-alylacetonitriles

The reaction of α-substituted 2-quinoxalylacetonitriles with 1-alkyl(aryl)imidazoles, -benzimidazoles, -1,2,4-triazoles and 5,6-dihydroimidazo[i,j]quinoline was studied. It was found that during the course of the reaction an unusually easy dealkylation of the azole ring takes place, while the aryl substituent is not split off. A reaction mechanism has been proposed including the formation of an ylide intermediate, followed by subsequent electrophilic attack on the C(2) position of the azolium ring. The applicability boundaries of the reaction studied and the spectral characteristics of the synthesized compounds were investigated.

Pseudo-cross-conjugated mesomeric betaines. 1. Synthesis of pseudo-cross-conjugated mesomeric betaines from quinoxaline derivatives

A new method for the synthesis of pseudo-cross-conjugated mesomeric betainic heterocyclic compounds with an angular nitrogen atom has been developed consisting in the reaction of 1,4-dielectrophile — α-carbethoxy-2-(3-chloro)quinoxalylacetonitrile with azoles. Experimental regularities have been studied and a reaction mechanism has been proposed including the stage of formation of an ylide from a quaternary azolium salt. A pseudo-crossconjugated mesomeric betainic heterocyclic compound containing a thiazole ring compound has been synthesized for the first time.

(HET) Arylation of substituted acetonitriles. 1. Synthesis of 2-amino-3-(benzimidazol-2-yl)pyrrolo [2,3,b]-quinoxalines

It was shown that hetarylation of benzimidazol-2-ylacetonitriles by 2,3-dichloro-quinoxaline proceeds at the methylene group. The reaction of 2-chloro-3-[α-cyano-α-(benzimidazol-2-yl) methylene]-3,4-dihydroquinoxalines formed with primary amines leads to 1-R-2-amino-3-(benzimidazol-2-yl)pyrrolo [2,3-b] quinoxalines.

Nucleophilic substitution in a series of 2-methylsulfonyl-5-chloropyrimidine-4-carboxylic acid derivatives

Abstractα-(2-Methylsulfonyl-5-chloropyrimidinoyl-4)-2-azahetarylacetonitriles were prepared by the reaction of 2-methylsulfonyl-5-chloropyrimidine-4-carboxylic acid chloride with 2-cyanomethylazaheterocycles.

Synthesis of 2-(2-hetaryl)-6-hydroxy-3-(R-amino)-2-hexenenitriles

The reaction of 2-hetaryl-2-(tetrahydrofuran-2-ylidene)acetonitriles and 6-chloro-2-(2-hetarylidene)-3-oxohexanenitriles with amines was studied. It was shown that the reaction of primary aliphatic amines with 6-chloro-2-(2-hetarylidene)-3-oxohexanenitriles takes place through a stage involving the formation of 2-hetaryl-2-(tetrahydrofuran-2-ylidene)acetonitriles followed by opening of the furanylidene fragment of the latter and the formation of 2-(2-hetaryl)-6-hydroxy-3-(R-amino)-2-hexenenitriles.