Cyclisations intramoléculaires: Accés aux 9-oxo-4H,9H-pyrrolo[1,2-a]thieno[2,3-d]pyridine et 4-oxo-4H,9H-pyrrolo[1,2-a]thieno[2,3-d]pyridine. Synthèse des pyrrolo[1,2-a]thieno[3,2-e][1,4]diazepine et pyrrolo[1,2-a]thieno[2,3-e][1,4]diazepine

Synthesis of 1-(2- or 3-thienylmethyl)methyl)pyrrole and some derivatives are described from halogenomethylthiophenes. The intramolecular cyclisation of carboxylic acid 19 and 20 leads to pyrrolothienopyridines 22 and 23. On the other hand azide-aldehydes 29 and 30 in aqueous acid mixture gave the pyrrolo[1,2a]thieno[2,3-e][1,4]diazepine.     

Synthesis of substituted pyrrolo[1,2-a][1,3]diazepine. A correction

The structure of a formerly described pyrrol[1,2-a][1,3]diazepine is corrected by synthesis. The correction is discussed by comparing physicochemical data and synthetic procedures for both substances.     

A novel practical synthesis of pyrrolo[1,2-a]thieno[2,3-e][1,4]diazepines

In an investigation of new heterocyclic systems, a novel way to obtain pyrrolo[1,2-a]thieno[2,3-e][1,4]diazepine 8 was effected by ring closure to the appropriate nitroaldehyde compound which was synthesized in five steps from 3-bromomethyl-2-nitrothiophene 1 .     

Synthesis of 5,6-dihydro-4H-pyrrolo[1,2-a]thieno[2,3-f][1,4]diazepines

The reduction of 1-[3-(thienyl-2-carbonitrile)]pyrrole, formed by condensation of 3-aminothiophene-2-carbonitrile with 2,5-dimethoxytetrahydrofuran, gave 1-[3-(thienyl-2-aminomethyl)]pyrrole. This compound was found to be a convenient intermediate for the preparation of 4-aryl-5,6-dihydro-4H-pyrrolo[1,2-a]thieno-[2,3-f][1,4]diazepines which was accomplished by two different synthetic routes.     

Pyrrolothienopyrazines: Synthèse de la pyrrolo[1,2-a]thieno[3,2-e]pyrazine et de la pyrrolo[1,2-a]thieno[2,3-e]pyrazine

The synthesis of pyrrolo[1,2-α]thieno[3,2-e]pyrazine and pyrrolo[1,2-α]-thieno[2,3-e]pyrazine is described. These syntheses could be achieved by intramolecular cyclization of 2- (and 3-) (1-pyrrolyl)-3- (and -2)-thienyl-amines obtained by hydrolysis of carbamates or by cleavage of the corresponding ureas. An original way giving better results was also studied via a Curtius rearrangement by reaction between the azide and aldehyde groupings. The synthesis of 2- (and -3)-2-formyl-1-pyrrolyl)-2- (and -3)-thenoylazide is described.     

Synthesis and reactivity of furo[2,3-e]pyrrolo[1,2-a][1,4]diazepin-9-one

A convenient method for the synthesis of furo[2,3-e]pyrrolo[1,2-a][1,4]diazepin-9-one is described. It has been C-alkylated with amine (piperidine, morpholine, 4-methylpiperazine) and N-alkylated with alkyl halides (methyl iodide and benzyl chloride).     

1,3-cyclohexanedione as the precursor of C4X-C6-C4Y systems. Synthesis of pyrrolo[2,3-e]indoles and thieno[2,3-e]indoles

A novel synthesis of substituted pyrrolo[2,3-e]indoles and thieno[2,3-e]indoles is described. This new approach uses 1,3-cyclohexanedione as the starting material. Diketone intermediates are obtained in four steps from the aforementioned ketone. Using these intermediates, the title compounds are synthesized efficiently.     

Synthesis of novel imidazo[1,2-a][3,1]benzothiazines 4, imidazo[1,2-a]-[1,2,4]benzotriazines 5, and 4H-imidazo[2,3-c]pyrido[2,3-e][1,4]oxazines 6

Starting from the readily available 2-aminobenzhydrols ( 7 ), 3-amino-1,2,4-benzotriazine ( 11 ) and 2-amino-3-pyridinol ( 12 ), novel derivatives of 5-phenyl-5H-imidazo[1,2-a][3,1]benzothiazine-2-carboxylic acid, ethyl ester ( 4 ), imidazo[2,1-c][1,2,4]benzotriazine-2-carboxylic acid, ethyl ester ( 5 ) and 4H-imidazo[2,3-c]pyrido-[2,3-e][1,4]oxazine ( 6 ) were prepared.     

Synthesis of isoxazolo[2,3-a]quinoxalines and pyrrolo[1,2-a]quinoxalines by 1,3-dipolar cycloaddition reaction

The isoxazolo[2,3-a]quinoxalines 11a,b and pyrrolo[1,2-a]quinoxalines 12a,b were selectively synthesized from the 2-substituted 6-chloroquinoxaline 4-oxides 10a,b . The pyrrolo[1,2-a]quinoxalines 12a,b were clarified to be produced by the ring transformation of the isoxazolo[2,3-a]quinoxalines 11a,b . The pyrrolo[1,2-a]quinoxalines 14a,b were obtained from both 2,6-dichloroquinoxaline 4-oxide 9 and compounds 12a,b .     

Furo[3,2-e]pyrrolo[1,2-α][1,4]diazepine and derivatives

The 5,10-dihydro-4H-furo[3,2-e]pyrrolo[1,2-α][1,4]diazepin-5-one ( 7 ) and furo[3,2-e]pyrrolo[1,2-α][1,4]diaze-pine ( 10 ) are synthesized from suitable isocyanates 3a,b in acetic acid. The reactivity of 10 (C- and N-alkyla-tion) is investigated.     

New synthesis of imidazo[4,5-e][1,3]diazepine

A new approach has been implemented in the synthesis of imidazo-[4,5,-e][1,3]diazepines consisting in the cyclization of 4,5-di-(cholormethyl)imidazole by urea derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1193–1195, September, 1993.     

New four-component Ugi-type reaction. Synthesis of heterocyclic structures containing a pyrrolo[1,2-a][1,4]diazepine fragment

[reaction: see text] We present a convenient synthesis of novel heterocyclic structures containing pyrrolo[1,2-a][1,4]diazepine fragment using a novel modification of four-component Ugi condensation. We demonstrate the usefulness and versatility of the developed approach for the synthesis of variously substituted compounds and discuss the scope and limitations of the chemistry involved.     

Synthesis of novel imidazo[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines and pyrimido[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines

Several 1 1-amino-5H-pyrrolo[2,1-c][1,4]benzodiazepines have been used as starting material to prepare a number of derivatives of 9H-imidazo[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines and 10H-pyrimido[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepines. The imidazole nucleus was built by reaction of amidines with ethyl bromopyruvate or aminoacetaldehyde dimethylacetal. Several derivatives of imidazo[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepine have been prepared by formylation of the pyrrole ring followed by formation of thioamides. Condensation of 11-amino-5H-pyrrolo[2,1-c][1,4]benzodiazepines with diethyl ethoxymethylenemalonate afforded intermediate diesters which were transformed into the corresponding 10H-pyrimido[1,2-a]pyrrolo[2,1-c]-benzodiazepines.     

Synthesis of substituted pyrrolo[2,3-e][1,3,4]thiadiazine 4,4-dioxides

A series of substituted pyrrolo[2,3-e][1,3,4]thiadiazine 4,4-dioxides is synthesized from 1-substituted-2-amino-3-cyanomethylsulfonyl-4,5-dimethylpyrroles.     

Synthesis and reactions of pyrrolo[1,2-a][3,1,6]benzothiadiazocines

A new synthesis of the thiadiazocine ring is reported together with an investigation of the diverse chemical reactions of pyrrolo[1,2-a][3,1,6]benzothiadiazocines.