Synthesis of 1-Alkoxy-4-amino-3,6-dioxo-1-phenyl-2,3,5,6-tetrahydro-1H-pyrrolo[3,4-c]pyridine-7-carbonitriles

Russian Journal of Organic Chemistry - 1-Alkoxy-4-amino-3,6-dioxo-1-phenyl-2,3,5,6-tetrahydro-1H-pyrrolo[3,4-c]pyridine-7-carbonitriles have been synthesized with high yields by reaction of...     

Synthesis of 6-Alkoxy- and 1,6-Dialkoxy-4-amino-1-aryl-3-oxo-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-7-carbonitriles

Russian Journal of Organic Chemistry - Base-catalyzed reaction of 3-aroyl-6-halopyridine-3,5-dicarbonitriles with alcohols involved successive regioselective pyrrole ring fusion at the pyridine [c]...     

Synthesis and cycloaddition reactions of ethyl glyoxylate imines. Synthesis of substituted furo-[3,2-c]quinolines and 7H-indeno[2,1-c]quinolines

Lewis acid catalyzed cycloaddition reactions of ethyl glyoxylate imines to dihydrofuran and indene yield substituted hexahydrofuro[3,2-c]- and tetrahydro-7H-indeno[2,1-c]quinolines respectively. Oxidation of the adducts with 2,3-dichloro-5,6-dicyanobenzoquinone affords the corresponding aromatic compounds.     

The synthesis of monomethoxy-6-methyl-7H-indeno[2,1-c]quinolines

A series of monomethoxy-6-methyl-7H-indeno[2,1-c]quinolines has been prepared by cyclization of the appropriate 1,3-dioxoindan-2-yl-ethylideneanilines, followed by Wolff-Kishner reduction.     

Synthesis of N-substituted 1H-indeno[2,1-b]pyridines

It was established that N-phenacyl and p-nitrophenacyl bromides and N-methyl-1-azafluorenium iodide, as well as N-phenacyl-7-nitro-1-azafluorenium bromide, are converted to N-substituted 1H-indeno[2,1-b]pyridines rather than to the corresponding yilds or indenoindolizines upon treatment with bases under various conditions. All of the pseudoazulenes of this type were isolated in the form of crystalline black or dark-violet substances. In contrast to pseudoazulenes of the 1H-indeno[1,2-b]-and 2H-indeno[2,1-c]pyridine series, they are stable both in the solid state and in solutions. 1H-1-Methylindeno[2,1-b]pyridine forms a perchlorate and a picrate (retention of the pseudoazulene structure) but is converted to N-methyl-1-azafluorenium chloride by the action of hydrogen chloride. Spectral characteristics are presented for all of the compounds obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1511–1515, November, 1980.     

Synthesis of 2,4-diamino-9H-indeno[2,1-d]pyrimidines

As part of a search for new antifolic, antimalarial, and antitumor agents, a series of 2,4-diamino-9H-indeno[2,1-d]pyrimidines was prepared by condensation of guanidine with substituted 2-alkoxy-3-cyano-1H-indenes. Base-catalyzed cyclization of 1,2-bis(cyanomethyl)benzenes afforded 2-amino-3-cyano-1H-indenes, which were converted into 3-cyano-2-methoxy-1H-indenes by acid hydrolysis and treatment of the resultant 1-cyano-2-indanones with diazomethane. Alternatively, 2-amino-3-cyano-1H-indenes could be transformed directly into 2-ethoxy-3-eyano-1H-indenes by reaction with ethanol and sulfuric acid. The 2,4-diamino-9H-indeno[2,1-d]-pyrimidines represent a new type of planar, tricyclic pyrimethamine analog, in which free rotation of the phenyl and pyrimidine rings is prevented by means of a methylene bridge.     

4-Substituted-4H-pyrrolo[2,1-c] [1,4]benzoxazines

The condensations of 1-(2-hydroxyphenyl) pyrroles with a variety of carbonyl compounds are shown to give new 4-substituted-4H-4-methylpyrrolo[2,1-c][1,4]benzoxazines. Some of the products were further functionalized. The ir, uv, and pmr spectra of the title heterocyclic system are discussed. Reaction of 1-(2-hydroxyphenyl) pyrrole with dimethyl acetylenedicarboxylate yielded dimethyl 3-(2-hydroxyanilino) phthalale; a mechanistic rationale which accounts for the result involves a rearrangement of the hypothetical Diels-Alder adduct.     

Synthesis of 5-oxo-5H-chromeno[3,4-c]pyridine-1-carbonitriles and features of their NMR spectra

Two different methods leading to 5-oxo-5H-chromeno[3,4-c]pyridine-1-carbonitriles were investigated. Reactions of 3-aminocrotonirile with substituted salicylaldehydes provided 5-oxo-5H-chromeno[3,4-c]pyridine-1-carbonitriles with the same substituent on positions 2 and 4 of the system. The reaction of 3-aminocrotonirile with variety of substituted 3-acetylcoumarins lead to 5-oxo-5H-chromeno[3,4-c]pyridine-1-carbonitriles with different substituents on positions 2 and 4. The structures of the products were confirmed by spectroscopic methods. The presence of nitrile moiety in the structures with fixed geometry caused the highly downfield shift of the aromatic proton at position 10 in ¹H NMR spectrum. The electronic factor of the substituents caused variation of this downfield shift.     

Synthesis of 1,4,6,7-tetrahydroimidazo[2,1-c] [1,2,4] triazines

From 2-methylthioimidazoline and phenaeylbromides in DMF there were obtained the 2-(2-methylthio-2-imidazolin-1-yl)aeetopht'nones 3a-3f . From these the substituted 3-phenyl-1,4,6,7-tetrahytlroimidazo[2,1-c][1,2,4]triazines 4a-4n were prepared upon reaction with hydrazine and methylhydrazine respectively. Compound 4a was degraded to the triazine 6. From the (2-methylthio-2-imidazolin-l-yl)-acetie acid ester 10, the imidazo[2,1-c] [1,2,4]triazines 11a-11c were prepared. Selective ethylation on the oxygen was achieved with 11b in the presence of Meerwein' salt.     

Synthesis of substituted indano[2,1-c]piperidines

Substituted indano[2,1-c]piperidines were obtained by selective hydrogenation over Re₂S₇ and also by reduction with sodium in alcohol of 3-methyl-2-azafluorene and its derivatives. The geometrical isomers of the products were isolated and characterized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1383, October, 1973.     

Synthesis of thieno[3,4-c] and thieno[3,2-c][2,1]benzothiazepines

Starting from [4,3-c] and [3,2-c] methyl chlorosulfonylthiophenecarboxylates the synthesis of ketones 7 and 8 is described. These compounds are the first two representatives of the new thieno[3,4-c] and thieno-[3,2-c][2,1]benzothiazepine ring systems. The formation of methyl 3-chlorosulfonylthiophene-2-carboxy-late is also revised.     

Synthesis of 5-phenyl-2,3,8,9-tetramethoxy-11H-indeno[1,2-c]isoquinoline

A novel approach to the title compound 10 starting with a conveniently available cinnamic acid is proposed. It involves a Friedel-Crafts reaction followed by the synthesis of the amide and subsequent cyclodehydration via a Bischler-Napieralski reaction.     

Facile and convenient syntheses of 6,11-dihydro-5H-indeno[1,2-c]isoquinolin- 5-ones and 6,11-dihydro-5H-indolo[3,2-c]isoquinolin-5-one

[reaction: see text] The synthesis of 6,11-dihydro-5H-indeno[1,2-c]isoquinolin-5-ones from the base-promoted condensation reaction of homophthalic anhydride and 2-(bromomethyl)-benzonitrile and a convenient method for the synthesis of indolo[3,2-c]isoquinolinones are described.     

Synthesis and Properties of 1,3-Diaryl-5,6-dihydro-8H-imidazo[2,1-c]-1,4-oxazinium Bromides

It has been established that the condensation of 3-(4-methoxyphenylamino)-5,6-dihydro-2H-1,4-oxazine with substituted phenacyl bromides occurs at the exocyclic nitrogen atom with formation of 3-aryl-3-hydroxy-1-(4-methoxyphenyl)-2,5,6,8-tetrahydro-3H-imidazo[2,1-c]-1,4-oxazinium bromides. By treatment of the latter with acetic anhydride 3-aryl-1-(4-methoxyphenyl)-5,6-dihydro-8H-imidazo[2,1-c]-1,4-oxazinium bromides are formed. The structures of the compounds synthesized were determined via ¹H NMR spectroscopy and X-ray diffraction.     

Synthesis of 5,6-dihydro-4H-pyrrolo[1,2-a][1,4]benzodiazepine and 10,11-dihydro-5H,12H-pyrrolo[2,1-c][1,4]benzodiazocine derivatives via cyclization of 2-aminomethylpyrroles

We have synthesized pyrrolo[1,2-α][1,4]benzodiazepine 6 and pyrrolo[2,1-c][1,4]benzodiazocines 12 and 13 from the corresponding 1-arylpyrrole 1d and 1-benzylpyrroles 7a and 7b by routes involving four and five steps, respectively.