V. V. Pirozhenko

Thiocyanation of N-arylsulfonyl-, N-aroyl-, and N-[(N-arylsulfonyl)benzimidoyl]-1,4-benzoquinone imines

Reactions of thiocyanate ion with N-aroyl-, N-arylsulfonyl-, and N-(N-arylsulfonylbenzimidoyl)-1,4-benzoquinone imines follow the 1,4-addition pattern, and the adducts undergo intramolecular cyclization to give the corresponding N-substituted 5-amino-1,3-benzoxathiol-2-ones as final products.

Reactions of N -aryl(methyl, trifluoromethyl)sulfonyl-1,4-benzoquinone monoimines with sodium sulfinates

In reactions with sodium sulfinates of N-substituted 1,4-benzoquinone monoimines with the quinoid ring having free positions 2 and/or 6 the fraction of products of 1,4-addition of the sulfinate ion grows in the series ArSO2 → MeSO2 → CF3SO2. In the case of 2,6-dimethyl derivatives the 1,6-addition is preferable, and the amount of products of 6,1-addition decreases.

Heterocyclization reactions of 2-(2-propynylthio)-4(1H)-quinazolinone derivatives when treated with electrophilic and nucleophilic reagents

Reaction of the potassium salt of 2-thioquinazolin-4-one with propargyl halides leads to formation of 2-propargylthioquinazolin-4-one derivatives, which undergo heterocyclization when they are treated with electrophilic or nucleophilic reagents and, depending on the nature of the cyclization agent, leads to formation of tricyclic systems with angular or linear structure.

Heterocyclization of functionalized heterocumulenes with C,N- and C,O-binucleophiles: IV. Reactions of 1-chloroalkylheterocumulenes and N-(1-chloroalkylidene)carbamates with 2-benzimidazolylacetonitriles and methyl 2-benzimidazolylacetates

Abstract1-Chloroalkyl isocyanates and 1-chloroalkylcarbodiimides undergo regioselective cyclization with nitriles and esters of 2-benzimidazolylacetic acid to give derivatives of 1-oxo and 1-arylimino-1,2,3,5-tetrahydrobenzo[4,5]imidazo[1,2-c]pyrimidine respectively. The cyclocondensation of 1,1-dichloroalkyl isocyanates or N-(1-chloroalkylidene)carbamates with nitriles and esters of 2-benzimidazolylacetic acid afforded 1,5-dihydrobenzo[4,5]imidazo[1,2-c]pyrimidin-1-one derivatives.

Heterocyclization of Functionalized Heterocumulenes with C,N- and C,O-Binucleophiles. 1. Cyclocondensation of 1-Chloroalkylheterocumulenes and N-(1-Chloroalkylidene)urethanes with 2-Cyanomethylpyridine

The interaction of 1-chloroalkyl isocyanates, 1-chloroalkylcarbodiimides, 1,1-dichloroalkyl isocyanates, and N-(1-chloroethylidene)-O-methylurethanes with 2-cyanomethylpyridine has been investigated. An effect of organic base has been detected on the regioselectivity of the cyclocondensation of 1-chloroalkyl isocyanates, which leads to 2,3-dihydro-1H-pyrido[1,2-c]pyrimidin-1-one or the isomeric 2,3-dihydro-1H-pyrido[1,2-c]pyrimidin-3-one. Irrespective of the cyclization conditions 1-chloroalkylcarbodiimides react with the formation of 1-imino-2,3-dihydro-1H-pyrido[1,2-c]pyrimidines. One type of product, a 1H-pyrido[1,2-c]pyrimidin-1-one, was also isolated from 1,1-dichloroalkyl isocyanates and N-(1-chloroalkylidene)urethanes.

Synthesis and stereochemical configuration of diastereomeric inherently chiral calixarenes with ABCH and ABCD type of substitution at the lower rim

By sulfonylation of tetra(p-tert-butyl)-27-propoxy-25-[N-(1-phenylethyl)carbamoylmethoxy]calix[4] arene diastereomeric inherently chiral calixarenes with the ABCH substitution at the lower rim were synthesized and separated by column chromatography. The alkylation of these compounds afforded the corresponding calixarenes with the ABCD substitution type. The absolute configuration of compounds was established by XRD analysis.

σ-Complexes in the pyrimidine series. 13. Reaction of 7- and 5-methoxyfuroxano-[3,4-d]pyrimidines with some C-nucleophiles

We have studied the reaction of isomeric 7-and 5-methoxyfuroxano[3,4-d]pyrimidines with carbanions of some CH acids. We have shown that regardless of the position of the substituent in the pyrimidine ring, nucleophilic attack occurs regioselectively at the C(7) atom. As a result, we have obtained the products of substitution at the methoxy group, and also anionicσ complexes and covalentσ adducts.

Synthesis of 4-oxo-1,4,5,6,7,8-hexahydro-1H-pyrazolo[3,4-e]-[1,4]diazepine-7-carbonitriles, -carboxamides, and -carboxylic acids

Products of intramolecular cyclocondensation of 5-amino-N-(2,2-dimethoxyethyl)pyrazolo-4-carboxamides, 7-hydroxy-5,6,7,8-tetrahydro-1H-pyrazolo[3,4-e][1,4]diazepin-4-ones, react with potassium cyanide in water affording 4-oxo-5,6,7,8-tetrahydro-1H-pyrazolo[3,4-e][1,4]diazepine-7-carbonitriles, which under the conditions of alkaline hydrolysis are converted into the corresponding carboxamides and carboxylic acids.

Synthesis and structure of [2-oxo(thioxo)tetrahydropyrimidin-4-yl]calix[4]arenes

Cone-shaped di- and tetrapropoxycalix[4]arenes functionalized at the upper rim with one or two 2-oxo(thioxo)tetrahydropyrimidine residues were synthesized by the Biginelli reaction of formylcalixarenes with urea (thiourea) and methyl acetoacetate. The steric structure of the products was studied by NMR and X-ray diffraction. The Biginelli reaction with dipropoxyformylcalixarene was diastereoselective, and it quantitatively produced the corresponding meso form. Tetrapropoxydiformylcalixarenes under analogous conditions gave rise to equimolar mixtures of racemic and meso compounds. The macrocyclic skeleton of the synthesized pyrimidine-containing calixarenes in crystal and in solution has a flattened cone conformation. (5-Methoxycarbonyl-2-oxotetrahydropyrimidin-4-yl)calixarene molecules in crystal undergo self-organization to form infinite chains via repeated inclusion of the methoxy group into the cavity of the neighboring macrocycle. Selforganization of bis(5-methoxycarbonyl-2-oxotetrahydropyrimidin-4-yl)calixarene with formation of analogous chains involves intermolecular hydrogen bonding NH ... O=C.

SYNTHESIS AND SOME CONVERSIONS OF 4-ARYL-6-METHYL-2-METHOXY(PHENYL)5-NITRO-1,4-DIHYDROPYRIMIDINES

The reaction of 1-arylidene-1-nitropropan-2-ones with O-methylisourea (or benzamidine) in the presence of aluminum oxide gave 4-aryl-6-methyl-2-methoxy(phenyl)-5-nitro-1,4-dihydropyrimidines. It was shown that the reactions of the compounds synthesized with electrophilic agents proceed at the exocyclic methyl group, as well as at the N(1), N(3), and C(5) atoms of the 1,4-dihydropyrimidine fragment of the molecule.