Reaction of indoles and 2-ketoindolines with some aldehydes

3,5-Di-tert-butyl-4-hydroxybenzaldehyde reacts with indole and 2-methylindole to give di(3-indolyl)methane derivatives but reacts with 2-ketoindoline and 1-methyl-2-ketoindoline to give 3-arylidene-2-ketoindoline derivatives. 2-Ketoindolines form 3-(o-hydroxybenzylidene)-2-ketoindolines with salicylaldehyde. They react with aryglyoxals to give 3-(2-ketoindolinyl)-aroylcarbinols, which are dehydrated to 3-phenacylidene-2-ketoindolines under the influence of acetic acid. Both the starting carbinols and these products form spiro[(2-ketoindoline)-3,5-(3-aryl-²-pyrazolines)] on reaction with hydrazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 40–44, January, 1973.     

Steroids

Summary A new method for the synthesis of steroido[17, 16-d]-3-methylpyrazoles has been proposed on the basis of a study of the alkaline decomposition and catalytic hydrogenation of steroido[17,16-d]-3-methylisoxazoles.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 410–416, 1966     

Pyrylium[2,3-b]indole salts

2-Ketoindoline and 1-methyl-2-ketoindoline condense with hydroxymethylene ketones in the presence of hydrogen chloride to give pyrylium[2,3-b]indole chlorides, which can be converted to 5-(3-oxindolyl)-²-pyrazolines by reaction with phenylhydrazine and to 5-(3-oxindolyl)-²-isoxazolines by reaction with hydroxylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1030–1032, August, 1972.     

New approach to the functionalization of δ-carboline derivatives

The possibility of transformation of 3-cyano-1-p-nitrophenyl--carbolin-2-one into 2-amino-3-cyano-1-p-nitrophenyl-1H-pyrido[3,2-b]indole derivatives and 2-imino-3-cyano-1-p-nitrophenyl-5H-pyrido[3,2-b]indole derivatives (-carbolines) is demonstrated. Methylation of 1-p-nitrophenyl-2-piperidino-1H--carboline followed by treatment with acetone in an alkaline medium yields 4-acetonyl-5-methyl-1,4-dihydro-5H-pyrido[3,2-b]indole derivative. The rearrangement of 2-arylimino-3-cyano-1-p-nitrophenyl-5H-pyrido[3,2-b]indoles into 2-(aryl)nitrophenylamino-3-cyano-5H-pyrido[3,2-b]indoles was accomplished on heating above the melting point or on treatment with potassium tert-butoxide. The structures of the resulting compounds were proved by ¹H and ¹³C NMR spectroscopy and X-ray diffraction analysis.     

Syntheses with heterocyclic β-enaminonitriles: A facile preparation of polyfunctionally substituted thiophene,thieno[3,2-b]pyridine and thieno[3,2-d]pyrimidine derivatives

Summary A convenientGewald synthesis of 3,5-diaminothiophene-2-carbonitrile derivatives (2) is reported. The synthetic potential of the -enaminonitrile moiety in2 has been explored; it proved to be a promising candidate for the synthesis of polyfunctionally substituted thieno[3,2-b]pyridines and thieno[3,2-d]pyrimidines.

---

Synthesen mit heterocyclischen -Enaminonitrilen: Eine einfache Methode zur Herstellung polyfunktionell substituierter Thiophen-, Thieno[3,2-b]pyridin- und Thieno[3,2-d]pyrimidinderivate

Zusammenfassung Eine bequeme Methode zur Herstellung von 3,5-Diaminothiophen-2-carbonitril-Derivaten (2) nachGewald wird vorgestellt. Das synthetische Potential der -Enaminonitrilfunktion von2 wurde untersucht.2 ist ein geeignetes Ausgangsmaterial für die Synthese polyfunktionell substituierter Thieno[3,2-b]pyridine und Thieno[3,2-d]pyrimidine.

     

The annelation of the 2-aminopyran-4-one ring to condensed thiophenes

The reaction of arylacetonitriles with the methyl ester of 3-hydroxybenzo[b]thiophene-2-carboxylic acid in the presence of a basic catalyst leads to the previously unreported 2-amino-3-arylbenzo[4,5]thieno[3,2-b]pyran-4-ones. Under the same conditions, the ethyl ester of 4,6-dimethyl-3-hydroxythieno[3,2-c]pyridine-2-carboxylic acid reacts to form derivatives of a new heterocyclic system, pyrano[2,3-4,5]-thieno[3,2-c]pyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1476–1478, November, 1983.     

New method of synthesis of δ-carbolines from 3-indolinone via pyrano[3,2-b]indoles

2-Arylidene-1-acetylindolin-3-ones were obtained from 1-acetylindolin-3-ones and p-substituted benzaldehydes or 4-pyridinecarboxaldehyde, by the action of malonodinitrile, andwere converted into 2-amino-4-aryl-5-acetyl-3-cyanopyrano[3,2-b]indoles. When heated with an aqueous-alcoholic solution of KOH, the latter compounds transform into 2-alkoxy-4-aryl-3-cyano--carbolines. The possible paths of formation of -carbolines and pyrano[3,2-b]indoles are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 230–235, February, 1985.     

Synthesis and rearrangement of cycloalkyl[1,2-e]oxazolo[3,2-a]pyrimidin-8/9-ones: an access to cycloalkyl[1,2-d]oxazolo[3,2-a]pyrimidin-5-ones

2-Substituted-4a-hydroxy-9H-cycloalkyl[1,2-e]oxazolo[3,2-a]pyrimidin-9-ones 2a-c were synthesized by an one-step cyclocondensation from the 5-substituted-2-amino-2-oxazolines 1a-c with ethyl 2-oxocyclohexanecarboxylate in ethanol at room temperature, and easily dehydrated to provide 2-substituted-9H-cycloalkyl[1,2-e]oxazolo[3,2-a]pyrimidin-9-ones 3. In refluxing xylene, the reaction conducted with various ethyl 2-oxocycloalkanecarboxylates led to the two isomeric 2-substituted-8/9H-cycloalkyl[1,2-e]oxazolo[3,2-a]pyrimidin-8/9-ones 3 and 2-substituted-5H-cycloalkyl[1,2-d]oxazolo[3,2-a]pyrimidin-5-ones 4. The structure of some compounds was unambiguously established using X-ray crystallography. According to results from the DSC analysis of compound 2a, formation of the thermodynamically stable pyrimidinones 4 could be related to an intramolecular rearrangement of kinetically controlled pyrimidinones 3.     

Studies in the imidazole series

A new synthesis of derivatives of thiazolo[3,2-a]benzimidazoles based on 2-halogenobenzimidazoles has been performed. The reaction of 2-chlorobenzimidazole with -halogeno ketones and the subsequent heating of the resulting 1-acylmethyl-2-chlorobenzimidazoles with thiourea has given 1-acylmethyl-2-mercaptobenzimidazoles. The cyclization of the latter under the action of mineral acids or water-abstracting agents has given a series of 2-alkyl-, 2-aryl-, and 2-heteryl-substituted thiazolo[3,2-a]benzimidazoles.For Communication XLIX, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 827–831, June, 1970.     

Acetals of lactams and acid amides. 35. Synthesis of condensed two- and three-ring pyridine systems on the basis of enamino amides

The synthesis of 2,3,5,6-tetrahydropyrrolo[3,2-c]pyrid-6-one was accomplished by rearrangement of 8H,1-cyano-8-dimethylaminomethylene-2,5,6,7-tetrahydropyrrolo[1, 2-c]pyrimidine. Pyrrolo[3,2-c]pyrimidine, 1,6-naphthyridine, and pyrimido[4,3-b]-azepine derivatives were synthesized on the basis of enamino dinitriles. The hydrolysis of 8H,1-cyano-8-dimethylaminomethylene-2,5,6,7-tetrahydropyrrolo[1,2-c]-pyrimidine in 50% CH₃COOH leads to a pyrrolo[1,2-c]pyrido[4,3-d]pyrimidine derivative. A similar dipyrido[4,3-d-1,2-c]pyrimidine derivative was obtained from 1-cyano-9-dimethylaminomethylene-2,5,6,7,8,9-hexahydropyrido[1,2-c]pyrimidine under these conditions, and 3,4-dioxo-3,4,7,8,9,10-hexahydropyrido[1,2-c]pyrano[4,3-d]-pyrimidine was synthesized bytreatment with a 1 N solution of HCl.See [1] for Communication 34.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 518–522, April, 1982.     

Regioselective Synthesis of Flindersine Analogues

6-Alkylpyrano [3,2-c] quinolin-5(2H)-ones(11a-e) were obtained in excellent yields by simply refluxing propynyl and butymyl ethers (6) of 4-hydroxy-1-alkylquinolin-2H-ones (2) in chlorobenzene for 10h, 5-Prop-2-ynyloxy-2H-pyrano [3,2-c] quinoline (12) was also obtained from the thermal rearrangement of 2,4-bis prop-2-ynyloxyquinoline (4).     

Synthesis and Some Transformations of Derivatives of Pyrido[3,2-b]indole (δ-Carboline)

The reactions of 2-dimethyliminomethyl-3-(p-nitrophenyl)aminoindole chloride with compounds with an active methylene center have been studied. A series of derivatives of -carboline have been synthesized. By the reaction of 3-ethoxycarbonyl-2-methyl-1-p-nitrophenylpyrido[3,2-b]indolinium chloride with the diethyl acetal of DMF the corresponding 2-dimethylaminovinyl derivative was synthesized which was converted into 5-p-nitrophenyl-1-oxo-1,10-dihydropyrano[3',4':5,6]pyrido[3,2-b]indol-5-ium chloride in the presence of acid.     

The synthesis of new azoniathiahelicenes

Synthesis of new azonia derivatives of thia[6]helicene ( 1 ) and thia[7]helicene ( 2 ) is described. The Knoevenagel condensation of 2‐methylbenzothieno[3,2‐a]quinolizinium salt ( 8 ) with appropriate arylaldehydes yielded 2‐(arylvinyl)benzothieno[3,2‐a]quinolizinium salts ( 9 and 10 ), respectively. Photocyclization of 2‐styrylbenzothieno[3,2‐a]quinolizinium salt ( 8 ) gave 7a‐azonia‐5‐thia[6]helicene ( 1 ) in 63% yield. Similarly, 2‐[2‐(2‐naphthyl)vinyl]benzothieno[3,2‐a]quinolizinium salt ( 10 ) afforded 7a‐azonia‐5‐thia[7]helicene ( 2 ) in 56% yield. The complete and unambiguous assignment of their ¹H‐ and ¹³C‐nmr spectra was performed by utilizing two‐dimensional nmr spectroscopic methods.     

Condensed O-, N-heterocycles by the transformation of azidoacrylates

Summary A number of furo[3,2-c]pyridines (4a–4d) and benzo[b]derivative (4e), as well as pyrrolo[2,3-4,5]furo[3,2-c]pyridine (8) were prepared by reaction of the corresponding iminophosphoranes, available from ethyl azidoheteroacrylates and triphenylphosphine, with phenyl isocyanate. The appropriate azidoheteroacrylates were used for the preparation of some substituted furo[3,2-b:4,5-b]dipyrroles (6). The reactions of the prepared compounds are described.

---

Kondensierte O-, N-Heterocyclen durch Umwandlung von Azidoacrylaten

Zusammenfassung Eine Anzahl von Furo[3,2-c]pyridinen (4a –4d), ein Benzo[b]derivat (4e) und Pyrrolo[2,3:4,5]furo[3,2-c]pyridin (8) wurden durch die Reaktion von Phenylisocyanaten mit den entsprechenden Iminophosphoranen dargestellt, die aus Ethyl-azidoheteroacrylaten und Triphenylphosphin leicht zugänglich sind. Die entsprechenden Azidoacrylate wurden zur Synthese einiger Furo[3,2-b:4,5-b]dipyrrole (6) verwendet. Die Reaktionen einiger dieser Verbindungen werden beschrieben.

     

Regioselective photocyclization of (e)‐2‐(2,3,6‐trichlorostyryl)‐benzothiazole and synthesis of 3,4‐dichloro‐ and 4‐chlorobenzothiazolo[3,2‐α]quinolinium chlorides: A synthetic and theoretical study

A high degree of regioselectivity is observed in the photochemically induced cyclization of (E)‐2‐(2,3,6‐trichlorostyryl)benzothiazole ( 1a ). According to the proposed mechanism, this compound was expected to afford two products, 3,4‐dichloro‐ and 1,4‐dichlorobenzothiazolo[3,2‐α]quinolinium chlorides ( 4a and 4a' , respectively). However, this reaction produced 3,4‐dichlorobenzazolo[3,2‐α]quinolinium chloride ( 4a ) as the sole product. On the other hand, irradiation of (E)‐2‐(2,3,5‐trichlorostyryl)benzothiazole ( 1b ) failed to produce the expected 1,3‐dichlorobenzothiazolo[3,2‐α]quinolinium chloride ( 4b ). Furthermore, (E)‐2,3‐difluorostrylbenzothiazole ( 1c ) also failed to give the corresponding 1‐fluorobenzothiazolo[3,2‐α]quinolinium fluoride ( 4c ). Interestingly, the irradiation of 2,6‐dichlorostyrylbenzothialole ( 1d ) produced 4‐chlorobenzothiazolo[3,2‐α]quinolinium chloride ( 4d ) in excellent yield. This paper presents the results of these investigations and a mechanistic rationale for the outcome of this reaction based on steric arguments and theoretical studies using a combination of molecular mechanics (MM+) and semiempirical quantum mechanical calculations (PM3/RHF/CI). Two‐dimensional high field nmr methods were employed to make complete assignments of the proton and carbon spectra of all new compounds.     

Condensed heterocycles with a thiazole ring.

Derivatives of new condensed heterocyclic systems — pyrido- and quinolino[1,2:3,2]thiazolo[4,5-b]pyrazines — were synthesized by condensation of 2,3-dichloropyrazine with 2-mercaptopyridine and 2-mercaptoquinolines.See [1] for Communicaton 17.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1276–1278, September, 1990.     

Synthesis of some 1 -oxo-1h-2,3,4,5-tetrahydro-benzofuro [3, 2-c]azepines

Condensation of O-phenylhydroxylamine with 1H-2,3,4,5,6,7-hexahydroazepine-2,4-dione in alcoholic hydrogen chloride solution gave 1-oxo-1H-2,3,4,5-tetrahydrobenzofuro[3,2-c]-azepine, while a similar condensation with 6,6-dimethyl-1H-2,3,4,5,6,7-hexahydroazepine-2,4-dione gave a mixture of 4,4-dimethyl-1H-2,3,4,5-tetrahydrobenzofuro[3,2-c]azepine and 2-oxo-3-(3,3-dimethyl-5-pyrrolidylidene)benzofuran. Tetrahydrobenzofuroazepines were also synthesized by Beckmann rearrangement of oximes of 1-oxo-1,2,3,4-tetrahydrobenzofuran and 3,3-dimethyl-1-oxo-1,2,3,4-tetrahydrodibenzofuran, which were obtained in turn by condensation of O-phenylhydroxylamine with dihydroresorcinol and dimedone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 149–153, February, 1973.     

Fluoro-containing Heterocycles: XIII. Fluoro-containing Derivatives of Thiazolo[3,2-<Emphasis Type="Italic">a</Emphasis>]-, Benzothiazolo[3,2-<Emphasis Type="Italic">a</Emphasis>]-, and Benzimidazo[3,2-<Emphasis Type="Italic">a</Emphasis>]quinazolinones

Reactions of 2-aminothiazole, derivatives of 2-aminobenzothiazole and 2-aminobenzoimidazole with polyfluorobenzoyl chlorides gave rise to acylation products that at heating in the diphenyl ether formed fluoro-containing derivatives of thiazolo[3,2-a]-, benzothiazolo[3,2-a]-, and benzimidazo[3,2-a]quinazolinone.     

Some substituted 4-aminothionaphtheno [3, 2-d] pyrimidines

Boiling 2-methyl-4-oxo-3,4-dihydrothionaphtheno[3,2-d]-pyrimidine with phosphorus oxychloride gives 2-methyl-4-chlorothionaphtheno [3,2-d]pyrimidine (II), in which the chlorine atom is mobile. Nucleophilic substitution of the mobile chlorine atom in compound II gives the 4-ethoxy,4-(N-piperidino),4-(N⁴-methyl-N-piperazino), 4-[2-(diethylamino)ethylamino],4-3-(diethylamino)-2-hydroxypropylamino]substituted derivatives.     

Preparation of 8-(5-oxoindeno [3,2-b]-4-pyridyl)-1-naphthoic acids

The condensation of 1-(1,3-indanedion-2-ylidene)-2-acenaphthenone with imines of -dicarbonyl compounds gave 2,5-dioxospiro 1,4,acenaphthene-1,4-dihydroindeno-[3,2-b]pyridines. Oxidation of the pyridines with air oxygen at room temperature without catalysts brings about cleavage of the C-C bond to give 8-(5-oxoindeno[3,2-b]-4-pyridyl)-1-naphthoic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 210–212, February, 1972.