Anellierte Thiopyrone, 2. Mitt. Thiopyrano[3,2-b]indol-4(5H)-on- und Thiopyrano[2,3-b]indol-4(9H)-on-2-carbonsäuren

Fused Thiopyrones, II; 2-Carboxylic Acids of Thiopyrano [3,2-b]indol-4(5H)-one and Thiopyrano[2,3-b]indol-4(9H)-one 3-Indolylthiofumaric acids 2 are cyclized by polyphosphoric acid (PPA) to yield the isomeric title compounds 6 and 8 .     

Anellierte Thiopyrone, 1. Mitt. Thiopyrano[3,2-b]indol-4(5H)-one,Thiopyrano[2,3-b]indol-4(9H)-one als Nebenprodukte

Fused Thiopyrones, I: Thiopyrano[3,2-b]-indol-4(5H)-ones, Thiopyrano[2,3-b]indol-4(9H)-ones as Byproducts The 3-(3-indolylthio)acrylic acids 3 cyclize with polyphosphoric acid (PPA) to yield the isomeric title compounds 4 and 5 , which are characterized by their sulfones, thiones and oxonol dyes.     

Untersuchungen an 1,3-Dicarbonylverbindungen, 25. Mitt. Pyrano[3,2-b]indol-4(5H)-on und 9-Chlor-1-oxo-1H-pyrrolo[1,2-a]indol-2-carbaldehyd

1,3-Dicarbonyl Compounds, XXV: Pyrano[3,2-b]indole-4(5H)-one and 9-Chloro-1-oxo-1H-pyrrolo[1,2-a]indole-2-carbaldehyde On treatment with POCl₃DMF the BF₂ chelate 2 , obtained from the 1,3-dicarbonyl compound 1 , yields the title substances 5 and 9 . Compound 5 is characterized by way of the thione 6 and the oxonol 7 , compound 9 by way of the 1,4-dihydropyridines 10 .     

Anellierte Thiopyrone, 4. Mitt.1): Indeno[1,2-b]-, Indolo[3,2,-b]-, [1]Benzofuro[3,2-b]- und [1]Benzothieno[3,2-b]thiopyrone

Fused Thiopyrones, IV: Indeno[1,2-b]-, Indolo[3,2-b]-, [1]Benzofuro[3,2-b]-, and [1]Benzothieno[3,2-b]thiopyrones The thiopyrones 2 are obtained from the corresponding thiopyranones 1 by dehydration with tritylperchlorate or SeO₂. Treatment of the benzofurane 2d with m-chloroperbenzoic acid (mCPBA) yields the thiopyrone-S, S-dioxide 3d. Starting from the benzothienothiopyrone 2e only one product, the thiophene-sulfone 3e , can be isolated.     

Anellierte Chinoline, 5. Mitt. 10-Hydroxy-10H-indolo[3,2-b]chinolin-5-oxid („Dioxychindolin”︁)

Fused Quinolines, V: 10-Hydroxy-10H-indolo[3,2-b]quinoline 5-Oxide (“Dioxyquindoline”) “Dioxyquindoline”, described by Fichter and Boehringer, is not 5, 11-Dihydro-10-hydroxy-10H-indolo[3,2-b]quinoline-11-one (2) but the title compound 4 .     

[1]Benzothieno[3,2-b]thiochromone und Thiochromono[3,2-b]indole

[1]Benzothieno[3,2-b]thiochromones and Thiochromono[3,2-b]indoles The 2-(3-benzo[b]thienyl)- and 2-(3-indolyl)-benzothioic acids 2 cyclize with polyphosphoric acid (PPA) to yield the title compounds 3 , which are characterized by their sulfones and thiones.     

Synthese von 7,12-Dihydro-indolo[3,2-d][1]benzazepin-6-(5H)-onen und 6,11-Dihydro-thieno-[3′,2′:2,3]azepino[4,5-b]indol-5(4H)-on

Synthesis of 7,12-Dihydro-indolo[3,2-d][1]benzazepin-6-(5H)-ones and 6,11-Dihydro-thieno-[3′,2′:2,3]azepino[4,5-b]indol-5(4H)-one The title compounds 4 and 6 were prepared by Fischer indole synthesis. 4a is substituted in 10-position by reaction with bromine in glacial acetic acid. A fast ring inversion is observed for the azepine ring in 4 and 6 .     

Synthesis and antiviral activity of new 4-(phenylamino)/4-[(methylpyridin-2-yl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acids derivatives

The synthesis of new 4-(phenylamino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (3a-l) derivatives and the new 4-[(methylpyridin-2-yl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (5a–c) derivatives was achieved with an efficient synthetic route. Ethyl 4-chloro-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylate (1) on fusion with appropriate substituted anilines or aminopicolines gave the required new ethyl 4-(phenylamino)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylates (2a–l) (52–82%) or new ethyl 4-[(methylpyridin-2-yl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylates (4a–c) (50–60%), respectively. Subsequent hydrolysis of the esters afforded the corresponding carboxylic acids (3a–l) (86–93%) and (5a–c) in high yield (80–93%). Inhibitory effects of 4-(phenylamino)/4-[(methylpyridin-2-yl)amino]-1-phenyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acids. Derivatives on Herpes simplex virus type 1 (HSV-1), Mayaro virus (MAY) and vesicular stomatitis virus (VSV) were investigated. Compounds 2d, 3f, 3a, and 3c exhibited antiviral activity against HSV-1, MAY, and VSV virus with EC₅₀ values of 6.8, 2.2, 4.8, 0.52, 2.5, and 1.0. None of these compounds showed toxicity for Vero cells.     

Untersuchungen an 1,3-Dicarbonylverbindungen, 15. Mitt. 4,5-Dihydro-5-alkyl-4-oxo-pyrano[3,2-b]indole

1,3-Dicarbonyl Compounds, XV: 4,5-Dihydro-5-alkyl-4-oxopyrano[3,2-b]indoles N-Alkylanthranilic acids react with chloroacetone/K₂CO₃ to form the 1-alkyl-2-acetyl-3-hydroxy-indoles 3 . The 1,3-dicarbonyl compounds 3 condense with dialkyl oxalates to yield the 1,3,5,6-tetra-carbonyl compounds 5 , which cyclize on heating with alcohols, saturated with HCl, to form the alkyl 4-pyrone-2-carboxylates 6 . The acids 8 , obtained from 6 , possess antiallergic activity. Decarboxylation of 8 affords the pyrono[3,2-b]indoles 9 . Condensation of 5 with triethyl orthoformate/acetic anhydride yield the alkyl 4-pyrone-3-ketocarboxylates 7 . Compounds 6 and 9 are converted to the thiocarbonyl compounds 11 and 12 . The amide 10 is obtained from 6c by reaction with ammonia.     

Reaktionen von 2-Amino-imidazo[2,1-b]-1,3,4-thiadiazolen mit Dicarbonsäureestern in Polyphosphorsäure (PPA)

Reactions of 2-Aminoimidazo[2,1-b]-1,3,4-thiazoles with Ethyl Dicarboxylates in Polyphosphoric Acid (PPA) The 2-amino-6-arylimidazo[2,1-b]-1,3,4-thiadiazoles 1d,e cyclise on heating in polyphosphoric acid (PPA) with ethyl malonate or ethyl diethylmalonate to yield the 2-aryl-6,8-dioxodihydro-6H-imidazo[2,1-b]-1,3,4-thiadiazolo[3,2-a] pyrimidines 3d,e or the 7,7-diethyl compounds 4d,e . Compounds 1a – f cyclise in PPA with ethyl succinate or ethyl phthalate to yield the 6-aryl-2-succinimido- or 6-aryl-2-phthalimido-imidazo[2,1-b]-1,3,4-thiadiazoles 5a, b, d-f and 6a – f . Compounds 1d,e were condensed with ethyl oxalate to yield the 2-(ethoxycarbonyl-formylamino)-6-arylimidazo[2,1-b]-1,3,4-thiadiazoles 7d,e. Ethyl levulinate with 1d,e in PPA probably forms 6-aryl-2-(2-methyl-5-oxo-Δ³-pyrrolino)imidazo [2,1-b]-1,3,4-thiadiazoles.     

Indoles,III Lactamisation of 4.9-Dihydropyrano [3.4-b]indol-1(3H)-ones. - A New Synthetic Route to the β-Carboline Ring System

Reaction of the pyrano[3.4-b]indolones 1a-d with aniline, benzylamine, phenylethylamine and propylamine at 200–210 °C yields the 2.3.4.9-tetrahydro-1H-pyrido[3.4-b]indol-1-ones 5a-j , which can be converted to the 2.3.4.9-tetrahydro-1H-pyrido[3.4-b]indoles 6a-j by reduction with LiAlH₄. After treatment with methylamine and 2 only the amides 3 and 4 could be isolated. Unsubstituted tetrahydro-β-carboline 7 is available by regioselective debenzylation of 6c .     

Untersuchungen an 1,3-Dicarbonylverbindungen, 16. Mitt. 4,5-Dihydro-4-oxo-indeno[1,2-b]pyran-2-carbonsäure

1,3-Dicarbonyl Compounds, XVI: 4,5-Dihydro-4-oxoindeno[1.2-b]pyran-2-carboxylic acid The title compound 5 is synthesized by the oxalic ester method from 2-acetyl-1-indanone. It has good antiallergic activity in the passive cutaneous anaphylaxis test, showing an ED₅₀ of 1.6 mg/kg. Derivatives of 5 and of the heterocyclic parent compound 6 are reported.     

Untersuchungen an 1,3-Dicarbonylverbindungen, 14. Mitt. 4-Oxo-4H-[1]benzofuro[3,2-b]pyrane und 4-Oxo-4H[1]benzothieno-[3,2-b]pyrane

1,3-Dicarbonyl Compounds, XIV: 4-Oxo-4H-[1]benzofuro[3,2-b]pyranes and 4-Oxo-4H-[1]benzothieno[3,2-b]pyranes The 1,3-dicarbonyl compounds 1 condense with dialkyl oxalates to form the 1,3,5,6-tetracarbonyl compounds 2 , which hydrolize under mildly alkaline conditions to give the ketocarboxylic acids 3 . Compounds 2 and 3 cyclize on heating with alcohols, saturated with HCl, to yield the alkyl 4-pyrone-2-carboxylates 4 . The acids 5 , obtained from 4 , decarboxylate on heating with quinoline/copper to give the heterocycles 6 . Compound 6b is also obtained from 1b by reaction with N,N-dimethylformamide dimethyl acetal (DMFDMA) and treatment with acid of the product 8b , whereas 1a and DMFDMA give the derivative 7a . Compounds 4 were characterized in the form of their amides 10 . The pyrylium salts 11 were obtained from 6 by reaction with dimethyl sulfate/HClO₄. Compounds 4 and 6 are converted to the thiocarbonyl compounds 12 and 13 by reaction with P₄S₁₀. Condensation of 2 with triethyl orthoformate/acetic anhydride yields the alkyl 4-pyrone-3-ketocarboxylates 14 . Compound 15b , formed by hydrolysis from 14b, afforded the 4-pyrone-3-carboxylic acid 16b by oxidative decarbonylation.     

Anellierte Thiopyrone, 5. Mitt.1): Darstellung und Reaktionen von 3-Formyl-indeno[1,2-b]-, -[1]benzofuro[3,2-b]-, -[1]-benzothieno[3,2-b]thiopyronen und 3-Formyl-thiopyrono[3,2-b]indolen

Fused Thiopyrones, V: Syntheses and Reactions of 3-Formyl-indeno[1,2-b]-, -[1]benzofuro[3,2-b]-, -[2]benzothieno[3,2-b]thiopyrones, and 3-Formyl-thiopyrono[3,2-b]indoles Alternative syntheses of the title compounds are described. The configuration of the oximes, obtained from the aldehydes, is proved. Furthermore the syntheses of the nitriles and the carboxylic acids is presented.     

Indoles,IV 9-Substituted 4,9-Dihydropyrano[3,4-b]indol-1(3H)-ones - Synthesis and Conversion into 2,3,4,9-Tetrahydro- 1H-pyrido-[3,4-b]indoles

Pyrano[3,4-b]indolones 3a-d are available from α-ethoxyalyllactones 1a, c and disubstituted hydrazines 2a, b without isolation of intermediates. In a two-phase system, however, the intermediate hydrazones 4a, c can be isolated. Conversion of 3a-d into β-carbolines was not possible by lactamisation but via the amides 8 and 9 .     

Synthesis and antibacterial activity of 3,4-dihyhdropyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4-ones

A series of 3,4-dihydropyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4-ones were synthesized by the reaction of ethyl 3-alkyl(aryl)carboxamidothieno[2,3-b]pyridine-2-carboxylates with aliphatic amines. The starting carboxamides were obtained via the reaction of ethyl 3-aminothieno[2,3-b]pyridine-2-carboxylate with acid chlorides. It is established that the synthesized pyridothienopyrimidinones possess antistaphylococcal activity. Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 42, No. 9, pp. 37–39, September, 2008.     

Reaktionen an Heterocyclen mit 2-Acyl-2-propenon-Teilstruktur, 5. Mitt. 2,5-Dioxo-2H,5H-[1]benzopyrano[4,3-b]pyridine durch Cyclisierung 3-substituierter 4-Aminocumarine

Reactions on Heterocycles Containing the 2-Acyl-2-propenone Structure, V: [1]Benzopyrano[4,3-b]-pyridine-2,5(2H, 5H)-diones by Cyclization of 3-Substituted 4-Aminocoumarines The synthesis of fluorescent [1]Benzopyrano[4,3-b]pyridine-2,5(2H, 5H)-diones 9 by a Wittig reaction using 4-chloro-2-oxo-2H-chromene-3-carbaldehydes 1 and phosphorane 2 is described. Aminolysis of the acrylic acid esters 3 leads to the 4-aminocoumarines 8 , which are cyclized thermically.     

3-Acyl-pyrano [2,3-b]indol-4-one

3-Acylpyrano[2,3-b]indol-4-ones The mixture which is obtained by treating 1-methyloxindole ( 1 ) with phosgene reacts with the alkali salts of the 1,3-dicarbonyl compounds 10a - 10d to yield the 3-acylpyrano[2,3-b]indol-4-ones 11a - 11d . Reactions with the salts of 1, 3-dimethylbarbituric acid and of 1 lead to the pyrone derivatives 12 and 13 , respectively.     

Synthesis of Some New Derivatives of Thiazolo[4,3-b]- and Thiazolo[2,3-b] quinazolone

The new 5H-thiazolo[4,3-b]quinazoline-3,5(1H)-diones 3, 4a–c, 5a–c and 5H-thiazolo[2,3-b]quinazoline-3,5(2H)-diones 9a–c, 11a–c were prepared by reaction of anthranilic acid with the 2-thiazolidinone-4-thione derivatives 1b, 6a–c, 7a–c and the 5-substituted 2-(alkylmercapto)-2-thiazolin-4-ones 8a-c, 10a-c , respectively.     

Imidazo[2,1-b]-1,3,4-thiadiazolo[3,2-a]pyrimidone-(6) aus 2-Acetoacetylamino-imidazo[2,1-b]-1,3,4-thiadiazolen

Imidazo[2,1-b]-1,3,4-thiadiazolo[3,2-α]pyrimidin-6-ones by Cyclisation of 2-(Acetoacetylamino)-imidazo[2,1-b]-1,3,4-thiadiazoles The 2-acetoacetylamino-6-methyl- (or -aryl) imidazo[2,1-b]-1,3,4-thiadiazoles 1, 2a–f cyclise on heating in polyphosphoric acid (PPA) to yield the tricyclic 2,8-dimethyl- or 2-aryl-8-methyl-imidazo[2,1-b]-1,3,4-thiadiazolo[3,2-α]pyrimidin-6-ones 3, 4a–f . Only 4c inhibits the growth of vaccinia viruses. The other compounds have no antiviral activity.