Reactions of 1,3-Dialkyl-5-amino-1,3-dihydro-2<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-2-ones with acetylacetone and ethyl acetoacetate

1,3-Dialkyl-5-amino-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones reacted with acetylacetone to give the corresponding 4-(1,3-dialkyl-2-oxo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-5-ylamino)pent-3-en-2-ones which underwent intramolecular cyclization to 1,3-dialkyl-5,7-dimethyl-1,3-dihydro-2H-imidazo[4,5-b]-[1,8]naphthyridin-2-ones on heating in polyphosphoric acid or diphenyl ether. Analogous reaction of 1,3-dialkyl-5-amino-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones with ethyl acetoacetate led to the formation of ethyl 3-(1,3-dialkyl-2-oxo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-5-ylamino)but-2-enoates whose cyclization afforded 1,3-dialkyl-8-hydroxy-7-methyl-1,3-dihydro-2H-imidazo[5,4-b][1,8]naphthyridin-2-ones.     

Modified synthesis of some 1-(pyrimidin-2-yl)-3-methyl-4-arylidenepyrazol-5(4<Emphasis Type="Italic">H</Emphasis>)-ones

2-[3-Methyl-4(4-dialkylaminobenzylidene)-5-oxo-4,5-dihydropyrazol-1-yl]cyclopenta[d]pyrimidin-4(3H)-ones were synthesized by consecutive transformation of 2-hydrazinocyclopenta[d]pyrimidin-4(3H)-one prepared from benzylideneaminoguanidine and ethyl 2-oxocyclopentanoate.     

Synthesis of 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1<Emphasis Type="Italic">H</Emphasis>-imidazo-[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids

Nitration of 2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-one gave its 5-nitro derivative which was subjected to alkylation with dimethyl sulfate, diethyl sulfate, and benzyl(dimethyl)phenylammonium chloride. The resulting 1,3-dimethyl-, 1,3-diethyl-, and 1,3-dibenzyl-5-nitro-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones were reduced to the corresponding 1,3-dialkyl-5-amino-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones, and the latter reacted with itaconic acid to produce 1-(1,3-dialkyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acids. 1-(2-Oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-5-yl)-5-oxopyrrolidine-3-carboxylic acid was obtained by analogous reaction with 5-amino-2,3-dihydro-1H-imidazo[4,5-b]-pyridin-2-one.     

Reaction of <Emphasis Type="Italic">N</Emphasis>-aryl-3-oxobutanethioamides with 2-amino-1,3-thiazole and 2-amino-1,3-benzothiazole

N-Aryl-3-oxobutanethioamides react with 2-amino-1,3-thiazole (2-amino-1,3-benzothiazole) in acetic acid to give mixtures of 7-methyl-5H-[1,3]thiazolo[3,2-a]pyrimidine-5-thione (2-methyl-4H-pyrimido-[2,1-b][1,3]benzothiazole-4-thione) and 5-arylimino-7-methyl-5H-[1,3]thiazolo[3,2-a]pyrimidines (4-arylimino-2-methyl-4H-pyrimido[2,1-b][1,3]benzothiazoles), whose ratio depends on the nature of the aryl substituent in the initial butanethioamide.     

Synthesis and antimicrobial activity of novel fused [1,2,4]triazino[5,6-<Emphasis Type="Italic">b</Emphasis>]indole derivatives

Synthesis of new fused systems of triazino[5,6-b]indole starting with preparation of 3-amino[1,2,4]-triazino[5,6-b]indole 1 by reaction of isatin with 2-aminoguanidinium carbonate in boiling acetic acid is presented [1]. Intermediate compound 1 reacted with aldehyde, ethyl chloroformate, triethyl orthoformate, and ninhydrine and gave new heterotetracyclic nitrogen systems, such as 3-(N ²-guanidinylimino)indole-2(1H)-one 2, 3-(N-ethoxycarbonylamino)-4H-[1,2,4]triazino[5,6-b]indole 3, 3-(N-ethoxymethyleneamino)-4H-[1,2,4]-triazino[5,6-b]indole 4, 3-(hydrazinothiocarbonylamino)-4H-[1,2,4]triazino[5,6-b]indole 5, respectively. N-(1,3-dioxoindene-2-ylidene)-4H-[1,2,4]triazino[5,6-b]indol-3-amine 6 was synthesized by reaction of compound 1 with aldehyde, ethyl chloroformate, triethyl orthoformate, and ninhydrine. New fused indole systems, pyrimido[2′,1′:3,4][1,2,4]triazino[5,6-b]indol-3(4H)-one 8, 9, 11, 12 and 1H-imidazo[2′,1′:3,4][1,2,4]triazino-[5,6-b]indol-2(3H)-one 10, were synthesized in the reaction of the intermediate 1 with bifunctional compounds. Structures of the products were elucidated from their elemental analysis and spectral data (IR, ¹H and ¹³C NMR and mass spectra). Antimicrobial activity of some synthesized compounds was tested.     

Halocyclization of 3-{[2-methyl(bromo)prop-2-en-1-yl]-sulfanyl}-5<Emphasis Type="Italic">H</Emphasis>-[1,2,4]triazino[5,6-<Emphasis Type="Italic">b</Emphasis>]indoles

Reactions of 3-[(2-bromoprop-2-en-1-yl)sulfanyl]-5H-[1,2,4]triazino[5,6-b]indole with bromine and of 3-[(2-methylprop-2-en-1-yl)sulfanyl]-5H-[1,2,4]triazino[5,6-b]indole with iodine and bromine afforded 3-halomethyl-10H-[1,3]thiazolo[3′,2′: 2,3][1,2,4]triazino[5,6-b]indol-4-ium halides whose structures were determined by ¹H NMR and X-ray analysis.     

Synthesis and Structure of 4-Indolyl-5-(thieno[3,2-<Emphasis Type="Italic">b</Emphasis>]pyrrol-6-yl)imidazoles

A procedure was proposed for regioselective acylation of methyl 2-methyl-4H-thieno[3,2-b]-pyrrole-5-carboxylate with 2-(3-indolyl)-2-oxoacetyl chloride. Reactions of the resulting methyl 6-[2-(3-indolyl)-1,2-dioxoethyl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate with aromatic aldehydes and ammonium acetate in acetic acid afforded the corresponding methyl 6-[2-aryl-4-(3-indolyl)imidazol-5-yl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylates. The structure of methyl 6-[2-(4-chlorophenyl)-4-(3-indolyl)imidazol-5-yl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate was studied by X-ray analysis.     

Recyclization of 1,3-dialkyl-6-nitro-1<Emphasis Type="Italic">H</Emphasis>-imidazo[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridine-2,5(3<Emphasis Type="Italic">H</Emphasis>,4<Emphasis Type="Italic">H</Emphasis>)-diones into imidazole derivatives

Treatment of 5-amino-1,3-dialkyl-2,3-dihydro-1H-imidazo[4,5-b]pyridin-2-ones with sodium nitrite in aqueous HCl gave 1,3-dialkyl-1H-imidazo[4,5-b]pyridine-2,5(3H,4H)-diones which were nitrated with potassium nitrate in sulfuric acid to 6-nitro derivatives, and the latter underwent recyclization into 4-amino-1,3-dialkyl-5-(1H-pyrazol-5-yl)-2,3-dihydro-1H-imidazol-2-ones by the action of hydrazine hydrate.     

Synthesis of arylmethylpyrimidinetriones and pyrimidoquinolinediones with fluorescent and nonlinear-optical properties

5-Arylmethyl-2,4,6-(1H,3H,5H)pyrimidinetriones and 12-aryl-8,12-dihydrobenzo[f]pyrimido[4,5-b]quinoline-9,11-(7H,10H)diones were synthesized, and their spectral-luminescence and nonlinear-optical properties were examined.     

Nitration of 1,3-dihydro-2<Emphasis Type="Italic">H</Emphasis>-imidazo[4,5-<Emphasis Type="Italic">b</Emphasis>]pyridin-2-one derivatives

Nitration of 1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one and its N-methyl derivatives at 0–5°C and 60°C gives 5-nitro-and 5,6-dinitro-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones, respectively. The latter can also be obtained by nitration of 5-mononitro derivatives under similar conditions. The nitration of 6-chloro-and 6-bromo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones and their N-methyl-substituted analogs leads to the formation of the corresponding 6-chloro(bromo)-5-nitro compounds. The same products are formed in the nitration of 5,6-dichloro-and 5,6-dibromo-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-ones. In this case, the process involves replacement of the halogen atom in position 5 of the pyridine fragment by nitro group. The nitration of 6-bromo-5-methyl-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one is accompanied by oxidation of the 5-methyl group to carboxy.     

Condensation of fluorine-substituted benzaldehydes with amines and cyclic ketones

Condensation of fluorine-containing benzaldehydes with naphthalen-2-amine or quinolin-6-amine and cyclic ketones (cyclopentanone, cyclohexanone, and 4-methylcyclohexanone) gave new fluorine-containing derivatives of cyclopenta[c]benzo[f]quinoline, benzo[a]phenanthridine, and cyclopenta[a]- and benzo[a]-[4,7]phenanthroline. Intermediate products, 2-[(fluorophenyl)(2-naphthylamino or quinolin-6-ylamino)methylidene] cyclohexanones, dihydrobenzo[f]quinolines, and dihydro-4,7-phenanthrolines, were isolated.     

Synthesis of 13-alkylbenzo[<Emphasis Type="Italic">f</Emphasis>]isochromeno[4,3-<Emphasis Type="Italic">b</Emphasis>]indole-5,7,12(13<Emphasis Type="Italic">H</Emphasis>)-triones by reaction of 2-alkylamino-1,4-naphthoquinones with ninhydrin

Reactions of 2-alkylamino-1,4-naphthoquinones with 2,2-dihydroxy-1H-indene-1,3(2H)-dione afforded 13-alkylbenzo[f]isochromeno[4,3-b]indole-5,7,12(13H)-triones.     

Electrophilic heterocyclization of 6-alken(yn)ylsulfanyl-pyrazolo[3,4-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(5<Emphasis Type="Italic">H</Emphasis>)-ones

6-Allylsulfanyl-1-arylpyrazolo[3,4-d]pyrimidin-4(5H)-ones react with iodine and sulfuric acid to give angular pyrazolothiazolopyrimidine derivatives. The reaction of 6-(prop-2-yn-1-ylsulfanyl)-1-(4-tolyl)-pyrazolo[3,4-d]pyrimidin-4(5H)-one with sulfuric acid gives angularly fused pyrazolo[4,3-e][1,3]thiazolo-[3,2-a]pyrimidin-4-one, whereas in the reaction with sodium methoxide linearly fused pyrazolo[3,4-d][1,3]-thiazolo[3,2-a]pyrimidin-4-one was formed. Linearly fused pyrazolo[3′,4′:4,5]pyrimido[2,1-b][1,3]thiazole derivatives were also obtained by reaction of 1-aryl-6-(3-phenylprop-2-en-1-ylsulfanyl)pyrazolo[3,4-d]pyrimidin-4(5H)-ones with sulfuric acid.     

Reactions of 2-(2-propynylsulfanyl)-5,6,7,8-tetrahydrobenzo[<Emphasis Type="Italic">b</Emphasis>]thieno[2,3-<Emphasis Type="Italic">d</Emphasis>]pyrimidin-4(<Emphasis Type="Italic">3H</Emphasis>)-one with arylsulfenyl chlorides

2-(2-propynylsulfanyl)-5,6,7,8-tetrahydrobenzo[b]thieno[2,3-d]pyrimidin-4(3H)-one with arylsulfenyl chlorides in chloroform gave products of anti-Markownikoff Ad _E-addition. The use of nitromethane as solvent in the presence of lithium perchlorate additives favored intramolecular electrophilic cyclization into 1-arylsulfanyl-1,2,6,7,8,9-hexahydro-4H-benzo[4,5]thieno[3,2-e][1,3]thiazolo[3,2-a]-pyrimidin-5-one.     

Three-Component Spiro Heterocyclization of Pyrrolediones with Malononitrile and Cyclic Enols

Ethyl 4,5-dioxo-2-phenyl-4,5-dihydro-1H-pyrrole-3-carboxylates reacted with malononitrile and five-membered cyclic enols, indan-1,3-dione and cyclopentane-1,3-dione to give 1-substituted ethyl 2-amino-3- cyano-2′,5-dioxo-5′-phenyl-1′,2′-dihydro-5H-spiro[indeno[1,2-b]pyran-4,3′-pyrrole]-4′-carboxylates and ethyl 2-amino-3-cyano-2′,5-dioxo-5′-phenyl-1′,2′,6,7-tetrahydro-5H-spiro[cyclopenta[b]pyran-4,3′-pyrrole]-4′-carboxylates, respectively.     

Synthesis and Study of Macroheterocyclic Compounds Based on 2,6-Dihydro-1<Emphasis Type="Italic">H</Emphasis>-cyclopenta[<Emphasis Type="Italic">cd</Emphasis>]phenalene-5,7-diimine

Previously unknown macroheterocyclic compounds containing cyclopenta[cd]phenalene and 1-phenyl-1,2,4-triazole, 1,3,4-thiadiazole, or pyridine fragments were synthesized by reaction of 2,6-dihydro-1H-cyclopenta[cd]phenalene-5,7-diimine with heteroaromatic diamines.     

Tetronic acid in reaction with aromatic aldehydes and 2-naphthylamine. Investigation of fluorescent and nonlinear-optical characteristics of compounds obtained

By Knoevenagel condensation and by three-component condensation 3-arylmethylenetetrahydrofuran-2,4-diones and previously unknown 8,11-dihydro-11-arylbenzo[f]furo[3,4-b]quinolin-10(7H)-ones were respectively synthesized. The luminescent spectra and nonlinear-optical characteristics of compounds obtained were investigated.     

Synthesis of oxo derivatives of <Emphasis Type="Italic">N</Emphasis>-(<Emphasis Type="Italic">p</Emphasis>-tolysulfonyl)hexahydrocycloalka[<Emphasis Type="Italic">b</Emphasis>]indoles

Hydroxymercuration-demercuration of N-p-tolysulfonyl-4,4a,9,9a-tetrahydro-3H-carbazoles and N-p-tolyl(or methyl)sulfonyl-1,3a,4,8b-tetrahydrocyclopenta[b]indoles leads to the formation of the corresponding N-p-tolylsulfonyl-2,3,4,4a,9,9a-hexahydro-1H-carbazol-2-ols and N-p-tolyl(or methyl)sulfonyl-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indol-2-ols. The latter are oxidized to 2-oxo derivatives with potassium dichromate. The oxidation of 2-methoxy-8-methyl-N-p-tolylsulfonyl-2,3,4,4a,9,9a-hexahydro-1H-carbazol-1-ol under analogous conditions gives 2-methoxy-8-methyl-N-p-tolysulfonyl-2,3,4,4a,9,9a-hexahydro-1H-carbazol-1-one.     

Cyclocondensation of 1<Emphasis Type="Italic">H</Emphasis>-indol-2-amine with pentane-2,3,4-trione 3-arylhydrazones

3-(Aryldiazenyl)-2,4-dimethyl-9H-pyrido[2,3-b]indoles were synthesized for the first time by cyclocondensation of 1H-indol-2-amine with pentane-2,3,4-trione 3-arylhydrazones.     

Synthesis and Antimycobacterial Activity of Hydrazides Based on Pyridoxine Derivatives

Pyridoxine derivatives, 3-hydroxy-2-methylpyridine-4- and -5-carbohydrazides, were synthesized according to optimized known procedures, and a method for the synthesis of 5-(hydroxymethyl)-2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridine-6-carbohydrazide was developed. The hydroxymethyl groups in positions 5 and 6 of 2,2,8-trimethyl-4H-[1,3]dioxino[4,5-c]pyridine showed different reactivities, and only the 6-hydroxymethyl group was selectively oxidized to aldehyde under mild conditions. The lactone ring in 5,6-dihydrofuro[3,4-b]pyridin-7(5H)-one was found to be stable to nucleophiles. The synthesized hydrazides showed no antimycobacterial activity.