A. N. Komogortsev

Three-Component Condensation of 2,4-Diaminoselenazole with Aldehydes and Meldrum’s Acid: Synthesis of 7-Aryl(alkyl)-Substituted 2-Amino-6,7-dihydro-4H-selenazolo[4,5-b]pyridin-5-ones

A method for the synthesis of 7-aryl(alkyl)-substituted 2-amino-6,7-dihydro-4H-selenazolo [4,5-b]pyridin-5-ones 5 based on three-component condensation of in situ–generated 2,4-diaminoselenazole 7 with aromatic (aliphatic) aldehydes 9 and Meldrums acid 10 was developed.

Multi-component condensation of 4-hydroxy-6-methyl-1H-pyridin-2-one with carbonyl compounds and Meldrum’s acid

A convenient method for the synthesis of earlier unknown substituted derivatives of 4-aryl-7-methyl-4,6-dihydro-3H-pyrano[3,2-c]pyridine-2,5-dione and ethyl 3-(4-hydroxy-6-methyl-2-oxo-1,2-dihydropyridin-3-yl)-3-arylpropionate was developed based on the multi-component condensation of 4-hydroxy-6-methyl-1H-pyridin-2-one, Meldrum’s acid, and carbonyl compounds.

Synthesis and optical properties of new photochromic systems based on 1,2-bis(2-methylbenzo[b]thien-3-yl) hexafluorocyclopentenes and 5,7-dihydro-1H-1,2,5,7,8-pentaaza-s-indacen-6-one or 1,7-dihydro-5-thia-1,2,7,8-tetraaza-s-indacen-6-one derivatives

New photochromic molecules based on 1,2-bis(2-methylbenzo[b]thien-3-yl)hexafluorocyclopentenes and fluorescent 5,7-dihydro-1H-1,2,5,7,8-pentaaza-s-indacen-6-one or 1,7-dihydro-5-thia-1,2,7,8-tetraaza-s-indacen-6-one derivatives were synthesized via nucleophilic substitution. Photochromic properties of the compounds and composite mixtures of fluorophores and photochrome were investigated. GRAPHICAL ABSTRACT

Three-component condensation of 5-aminoimidazole derivatives with aldehydes and Meldrum’s acid. Synthesis of 3,4,6,7-tetrahydroimidazo[4,5-b]pyridin-5-ones

A convenient method for the synthesis of the earlier unknown substituted 3,4,6,7-tetrahydroimidazo[4,5-b]pyridin-5-ones was developed based on a three-component condensation of 5-aminoimidazole derivatives, aldehydes, and Meldrum’s acid. Unstable aminoimidazole derivatives were readily formed in situ by decarboxylation of 5-amino-4-imidazolecarboxylic acids in acidic medium at room temperature, whose sodium salts were obtained by the alkaline hydrolysis of the corresponding, readily available esters.

Multicomponent condensation of 1,2-dihydropyrazol-3-one derivatives with carbonyl compounds and Meldrum´s acid

A convenient method for the synthesis of earlier unknown 3-aryl-3-(3-oxo-2,3-dihydro-1H-pyrazol-4-yl)propionic acid derivatives was developed based on the multicomponent condensation of 1,2-dihydropyrazol-3-ones, carbonyl compounds, and Meldrum´s acid.

Synthesis and structure of 6-aryl-6,7-dihydro-2H-imidazo[5,1-c][1,2,4]triazole-3,5-diones

An approach to the synthesis of earlier unknown substituted 6-aryl-6,7-dihydro-2H-imidazo[5,1-c][1,2,4]triazole-3,5-diones was developed, which is based on the reaction of 5-arylaminomethyl-2,4-dihydro[1,2,4]triazol-3-ones with 1,1′-carbonyldiimidazole. The structure of one of the products was unambiguously established by X-ray diffraction analysis.

Three-component condensation of 3-aminothiophene derivatives with isatines and Meldrum’s acid. Synthesis of 2,5′-dioxo-3′-phenyl-5′,6′-dihydro-4′H-spiro[indoline-3,7′-thieno[3,2-b]pyridine]-2′-carboxylic acids

A method for the synthesis of 2,5′-dioxo-3′-phenyl-5′,6′-dihydro-4′H-spiro[indoline-3,7′-thieno[3,2-b]pyridine]-2′-carboxylic acids was elaborated based on the three-component condensation of 3-aminothiophenes, Meldrum’s acid, and isatines.

Multicomponent condensation of 6-acetyl-5,7-dihydroxy-4-methylchromen-2-one with aldehydes and Meldrum´s acid

Previously unknown 6-acetyl-10-aryl-5-hydroxy-4-methyl-9,10-dihydropyrano[2,3-f]-chromene-2,8-diones were synthesized by multicomponent condensation of 6-acetyl-5,7-dihydroxy-4-methylchromen-2-one, aromatic aldehydes, and Meldrum´s acid. A fundamen-tal possibility of interconversion of substituted 6-acetyl-10-aryl-5-hydroxy-4-methyl-9,10-dihydropyrano[2,3-f]chromene-2,8-diones and methyl 3-(6-acetyl-5,7-dihydroxy-4-meth-yl-2-oxo-2H-chromen-8-yl)-3-arylpropionates was demonstrated.

Synthesis of 2-alkyl-5-phenylaminomethyl-2,4-dihydro-3H-[1,2,4]triazol-3-ones based on 2-alkyl-6-phenyl-6,7-dihydro-3H-imidazo-[5,1-c][1,2,4]triazole-3,5(2H)-diones

A new convenient method for the synthesis of earlier unknown 2-substituted derivatives of 5-phenylaminomethyl-2,4-dihydro-3H-[1,2,4]triazol-3-ones was developed. The method involved the alkaline hydrolysis of 2-alkyl-6-phenyl-6,7-dihydro-3H-imidazo[5,1-c][1,2,4]-triazole-3,5(2H)-diones obtained by alkylation of 6-phenyl-6,7-dihydro-2H-imidazo[5,1-c]-[1,2,4]triazole-3,5(2H)-diones.