V. A. Artemov

Ethyl 4-bromocrotonate in the synthesis of pyrido[3′,2′∶4,5]thieno[3,2-d]pyridin-2(1h)-ones

Pyrido[3′,2′∶4,5]thieno[3,2-d]pyridin-2(1H)-ones were synthesized from 3-cyano-2(1H)-pyridinethiones and ethyl 4-bromocrotonate.

N-acetylchloroacetamide in the synthesis of functionally-substituted pyrido[3′,2′∶4,5]-thieno[3,2-d]pyrimidin-4(3H)-ones

Abstract3-Cyano-2(1H)-pyridinethiones react with N-acetylchloroacetamide in ethanol in the presence of KOH to give pyrido[3′,2′∶4,5]thieno[3,2-d]pyrimidin-4(3H)-ones.

Regioselective synthesis of substituted thieno[2,3-b]pyrimidines and pyrido[3′,2′:4,5]thienopyrimidines and their [3,2-d]selenopheno analogs from 3-cyanopyridine-2(1H)-thiones, 3-cyano-pyridine-2(1H)-selenones, and N-cyanochloracetamidine

Abstract3-Cyanopyridine-2(1H)-thiones and 3-cyano-2(1H)-selenones undergo heteroannelation with N-cyano-chloracetarnidine to give thieno[2, 3-b]pyridines,selenopheno[2, 3-b]pyridines, 2, 4-diantinopyrido-[3′, 2′:4, 5]thieno[3, 2-d]pyritnidines, and 2, 4-diamittopyrido[3′, 2′:4, 5]selenopheno[3, 2-d]pyritnidines, which were converted to compounds containing triazine, anzinopyrimidine, and pyrimidinedione rings.

Derivatives of 4-halocrotonic acids, convenient reactants in the synthesis of heterocycles. (Review)

Literature data are reviewed for the first time on the use of 4-halocrotonic acid derivatives in the synthesis of five-and six-membered heterocycles containing one or several heteroatoms in the ring, and their annelated analogs.

Synthesis of pyrido[3′,2′:4,5]thieno[2,3-c]cinnolines — A new heterocyclic system

Pyrido[3′,2′:4,5]thieno[2,3-c]cinnolines, new heterocyclic compounds, were obtained in three steps: 1) alkylation of 3-cyanopyridine-2(1H)-thiones by o-nitrobenzyl bromide to give 2-(o-nitrobenzyl)thio-3-cyanopyridines, 2) closure of the thiophene ring in these intermediates to give 3-amino-2-(o-nitrophenyl)thieno[2,3-b]pyridines, and 3) closure of the pyridazine ring by condensation of the amino and nitro groups in triethyl phosphite, leading to the final heterocyclic system.

SYNTHESIS OF 2,7-NAPHTHYRIDINES BY THE RECYCLIZATION OF TRIMETHYLFORMYL-PIPERIDONE

The structure of the product of interaction of the sodium salt of 1, 2, S-trimethyl-3 formylpiperid-4-one with cyanothioacetamide was specified. It was shown that the Knoevenagel adduct formed at the first stage in basic conditions undergoes recyclization with the formation of 1, 2,3,5,6, 7, 8, 8a-octahydro-l-oxo-6, 7, 8a-trimethyl-4-cyano-2, 7-naphthyridine-3-thione, the structure of which was confirmed by the data of physicochemical methods of analysis and chemical conversions.

2-Bromo-i-phenylethylidenemalononitrile in the synthesis of thieno[3,2-b]pyridines and thiazolo[4,5-b]pyridines

A novel regioselective synthesis of thieno[3, 2-blpyridines and thiazolo[4,5-blpyridines from 2-bromo-I-phenyl ethylidenemalononitrile is proposed. In the case of the thiazolo[4, 5-b]pyridines, the intermediate 5-(2, 2-dicyano-l-phenylvinyl)thiazoles were separated. Formation of the thiazolo(4,5-b]pyridines was confirmed by x-ray analysis.

2,N-dicyanoacetamidine in the regioselective synthesis of pyrido[2,3-d]uracils

A new regioselective method of synthesizing functionally substituted pyrido[2,3-d]uracils from 2,N-dicyanoacetamidine is proposed. 3-Cyanopyridinecyanoimidines and 4-amino-2-bromopyrido[2, 3-d]pyrimidine hydrobromides were obtained as intermediate compounds. The structures of the compounds obtained were established by data of elemental analysis, NMR, IR, and mass spectra.