Synthesis of substituted benzo[g]isoquinolines and 8-azabenzo[a]fluoranthenes

The conversion of l,3-dimethyl-2,6-diphenyl-4-benzyl-4-piperidol and its N-unsubstituted analog by means of pyridine N-oxide to 3-methyl-2,6-diphenyl-4-benzylpyridine (I) is accompanied by the formation of l,2-diphenyl-l,2-bis(3'-methyl-2',6'-diphenyl-4'-pyridyl)ethane, which was obtained under the same conditions directly from y-benzyl-substituted pyridine I. The initial product in the catalytic dehydrocyclization of pyridine baseI is l,3-diphenylbenzo[g]isoquinoline, which is subsequently partially converted to 7-phenyl-8-azabenzo[a]fluoranthene. Spectral data for these heterocyclic compounds and the characteristics of the substances obtained by oxidation of them are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 648–651, May, 1979.     

Bridgehead nitrogen heterocycles. VI. The reaction of 1-amino- and 1,2-diaminopyridinium salts with β-dicarbonyl compounds

1,2-Diaminopyridinium iodide underwent reaction with ethyl acetoacetate to form 1,4-dihydro-2-methyl-4-oxopyrido[1,2-a]pyrimidin-1-ium iodide, and with acetyl acetone it gave 2,4-dimethylpyrido[1,2-a]pyrimidin-5-ium iodide. Though 2-acetylcyclohexanone gave the corresponding 5-methyl-1,2,3,4-tetrahydropyrido[1,2-a]quinazolin-11-ium iodide, no reaction was observed with 2,6-dimethyl-3,5-heptanedione, 1-benzoylacetone, 1,3-diphenyl-1,3-propanedione and its p-methoxyphenyl derivative. However, 1-aminopyridinium iodide and acetyl acetone in the presence of base gave 3-acetyl-2-methylpyrazolo[1,5-a]pyridine and 1-amino-2-methylpyridinium iodide yielded the corresponding 3-acetyl-2,7-dimethylpyrazolo[1,5-a]pyridine. With ethyl acetoacetate, the latter salt formed 3-ethoxycarbonyl-2,7-dimethylpyrazolo[1,5-a]pyridine but with 2,6-dimethyl substituents in the pyridine ring no condensation occurred. Reaction of 1-amino-2-methylpyridinium iodide with benzaldehyde gave N-benzalimino-2-methylpyridinium iodide which, on treatment with base, resulted in the formation of 2-picoline and benzonitrile, providing a convenient method of deamination.     

Alkylation of enolates by 3-methyl-4-chloro-4,5,6,7-tetrahydrobenz[1,2-d]isoxazole

3-Methyl-4-chloro-4,5,6,7-tetrahydrobenz[1,2-d]isoxazole was synthesized from 3-methyl-4-oxo-4,5,6,7-tetrahydrobenz[1,2-d]isoxazole. The compound is used in the alkylation of malonic ester and methoxytetralone enolates. Bi- and tetracyclic derivatives of the pyridine and hydropyridine series were obtained by catalytic hydrogenation of the alkylation products.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1379–1384, October, 1990.     

Free Radicals: XXVII. Synthesis of 2,6-Diphenyl-4-[p-(2,6-diphenyl-4-pyridyl)phenyl]pyranyl

Starting with 2,6-diphenyl-4-(p-tolyl)pyridine a synthesis of 2,6-diphenyl-4-[p-(2,6-diphenyl-4-pyridyl)phenyl]pyrylium perchlorate was performed. By reduction of the latter the corresponding radical was obtained. The radical was shown to be unstable with respect to oxygen.     

Synthesis of the Upstream Terminal Disaccharide of the O-Antigenic Polysaccharide of Vibrio cholerae O37

The terminal disaccharide of the O-antigenic polysaccharide of Vibrio cholerae O37, 4-O-methyl-α-D-QuiNAc-(1→4)-α-d-QuiNAc, was synthesized as methyl glycoside involving glycosylation between glycosyl donor ethyl 2-azido-3-O-benzyl-2,6-dideoxy-4-O-methyl-6-iodo-1-thio-α-d-glucopyranoside and glycosyl acceptor methyl 2-azido-3-O-benzyl-2,6-dideoxy-6-iodo-α-d-glucopyranoside. Dehalogenation, global deprotection, and reduction of the azide to amine were effected in one step by catalytic hydrogenation. It was followed by selective N-acetylation to give the desired deprotected disaccharide.     

Studies on organophosphorus compounds—V: Pyridines from secondary car☐amides and HMPA

A new pyridine synthesis has been found by refluxing certain simple secondary car☐amides in HMPA. Thus 2,6-dimethylpyridine, 2-ethyl-6-methylpyridine, 2,3,6-trimethylpyridine, 2-ethyl-3,6-dimethylpyridine, 2-benzyl-6-methyl-3-phenylpyridine, 2-ethyl-3-methyl-5,6,7,8-tetrahydroquinoline and 2-t-butyl-6-methylpyridine were prepared in 15–40% yield.     

Preparation of 4-bromo-1-hydroxypyrazole 2-oxides by nitrosation of α-bromo-α,β-unsaturated ketoximes

Nitrosation of the oximes of 3-bromo-3-penten-2-one, 3-bromo-4-phenyl-3-buten-2-one, and 2-bromo-1,3-diphenyl-2-propen-1-one using sodium nitrite in acetic acid gave low yields of 4-pyrazolone 1,2-dioxides. Nitrosation using butyl nitrite in the presence of copper(II) sulfate and pyridine in aqueous ethanol produced insoluble copper complexes from which 3,5-dimethyl-, 3-methyl-5-phenyl-, and 3,5-diphenyl-4-bromo-1-hydroxypyrazole 2-oxides could be liberated by treatment with dilute potassium hydroxide, filtration, and acidification of the filtrate. High yields were obtained with the first two oximes, but, presumably due to unfavorable stereochemistry of the oxime, the diphenyl derivative gave a lower yield of the complex, accompanied by 4-bromo- and 4-nitro-3,5-diphenylisoxazole and 4-oximino-3,5-diphenyl-4,5-dihydroisoxazole.     

新型2,6-双(3,5-二取代吡唑基-1-羰基)吡啶的合成

报道了四种吡唑衍生物和它们四种新型的杂环酰胺衍生物的合成 ,它们是 3 ,5 二甲基吡唑 (1) ,5 甲基 3 苯基吡唑(2 ) ,3 ,5 二苯基吡唑 (3 ) ,5 甲基 3 二茂铁基吡唑 (4 ) ,2 ,6 双 (3 ,5 二甲基吡唑基 1 羰基 )吡啶 (5 ) ,2 ,6 双 (5 甲基 3 苯基吡唑基 1 羰基 )吡啶 (6) ,2 ,6 双 (3 ,5 二苯基吡唑基 1 羰基 )吡啶 (7)和 2 ,6 双 (5 甲基 3 二茂铁基吡唑基 1 羰基 )吡啶 (8) .并对它们进行了元素分析 ,FT IR ,1HNMR和13 CNMR等波谱分析 .     

The synthesis of 4-benzylamino-6-methyl-1H-pyrrolo[3, 2-c]pyridine and 4-benzylamino-6-methyl-1H-pyrrolo[2, 3-b]pyridine

4-Benzylamino-6-methyl-1H-pyrrolo[3,2-c]pyridine ( 2 ) and 4-benzylamino-6-methyl-1H-pyrrolo[2,3-b]pyridine ( 3 ) were synthesized as deaza analogues of the anxiolytic agent 4-benzylamino-2-methyl-7H-pyrrolo[2,3-d]pyrimidine ( 1 ). The 1-deaza analogue (2) was prepared via a multi-step procedure from a pyrrole precursor, 1-benzyl-2-formylpyrrole ( 4 ) while the 3-deaza analogue 3 was synthesized from a pyridine precursor, 2-amino-3,6-dimethylpyridine ( 12 ).     

Synthesis and configuration of trans-1-amino-4-benzyl-2,6-dimethylpiperazine as an intermediate of semi-synthetic rifamycins

The synthesis of trans-1-amino-4-benzyl-2,6-dimethylpiperazine (1b), trans-4-benzyl-2,6-dimethylpiperazine (VIIb) and trans-2,6-dimethylpiperazine (IIb) are described, by condensation of N-benzyl-1,2-propanediamine with α-bromopropionate and successive thermal cyclization and reduction with lithium aluminum hydride. The assignment of the cis, trans configuration to the isomers was based on a thorough examination of the ring proton nmr signals of the two isomers of 4-benzyl-2,6-dimethylpiperazine (VIIa and VIIb) interpreted in terms of conformational considerations.     

The reaction of 2,6-diphenyl-2,3,5,6-tetrahydro-4H-thiopyran-4-one with sulfuryl chloride

2,6-Diphenyl-2,3,5,6-tetrahydro-4H-thiopyran-4-one was treated with one, two, and three equivalents of sulfuryl chloride in the presence of pyridine to give the dihydrothiopyranone 2 , the 3-chlorodihydrothiopyranone 3 , and the triehlorotetrahydrothiopyranone 4 , respectively. Compound 4 was converted to 3-chloro-2,6-diphenyl-4H-thiopyran-4-one by pyrolysis and to 3-hydroxy-2,6-diphenyl-4H-thiopyran-4-one on treatment with alcohols. Several pyrylium dyes were prepared from the latter compounds.     

Synthesis and configuration of 4-alkyl-2-methyl-3,4-diphenyl-1,2-thiazetidine 1,1-dioxide

4-Alkyl-2-methyl-3,4-diphenyl-1,2-thiazetidine 1,1-dioxide 5, 6 and 7 were obtained from 2-methyl-3,4-diphenyl-1,2-thiazetidine 1,1-dioxide 1 by reaction of its anion 4 with alkyl halides. cis- and trans-Configuration of the 4-alkylated products were determined by ¹H-nmr and NOE difference spectro-scopy studies.     

Dmap-Catalyzed Synthesis of Novel Pyrrolo[2,3-D]Pyrimidine Derivatives Bearing an Aromatic Sulfonamide Moiety

4-(N,N-Dimethylamino)pyridine (DMAP), with a dual role as a basic nucleophilic catalyst, was shown to be a highly efficient catalyst for the synthesis of some new N-(2-aryl-7-benzyl-5,6-diphenyl-7H-pyrrolo[2,3-d]pyrimidin-4-yl)benzenesulfonamides through the reaction of 2-aryl-7-benzyl-5,6-diphenyl-7H-pyrrolo[2,3-d]pyrimidin-4-amines (7-deazaadenines) with benzenesulfonyl chlorides. It was also found that the use of DMAP under solvent-free conditions is much more effective than other catalytic systems such as pyridine as both the catalyst and solvent, t-BuOK in t-BuOH, Et₃N in ethanol (EtOH), and even DMAP in dimethylformamide (DMF). The influences of the reaction parameters, temperature, and the catalyst amount, on the catalytic performance have been studied. All synthetic compounds were characterized on the basis of their full spectral data.     

Synthesis and molecular structure of 4-nitro-9-phenyl-1H-and 9-hydroxy-3-oxo-9-phenyl-2,3-dihydro-9H-indeno-[2,1- c ]pyridines and 3,7-diphenyl-3a, 4,5,6-tetrahydroindeno[2,1- c ]isoxazolo[5,4- d ]pyridine

The 4-nitro derivatives and an oxidation by-product, 9-hydroxy-2-methyl-3-oxo-9-phenyl-2,3-dihydro-9H-indeno[2,1-c]pyridine were obtained by the nitration of N-alkyl-9-phenyl-2,3-dihydro-1H-indeno-[2,1-c]pyridines with sodium nitrite in acetic acid. Their molecular structures were studied by X-ray structural analysis. The product of [2+3] cycloaddition, 5-methyl-3,7-diphenyl-3a, 4,5,6-tetrahydroindeno[2,1-c]isoxazolo[5,4-d]pyridine, was obtained by the interaction of 2-chloro-1-hydroxy-2-phenylazomethine with 2-methyl-9-phenyl-2,3-dihydro-1H-indeno[2,1-c]pyridine. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1390–1399, September, 2007.     

Synthesis and transformations of 1-methyl-4-azafluorene

By means of catalytic dehydrocyclization of dimethyl-substituted 2-phenylpyridines in a pyridine ring to 1(2,3)methyl-4-azafluorenes with subsequent oxidation, synthesis of alkaloid onychine — 1-methyl-4-azafluorene — several of its isomers were achieved. Using 1-methyl-4-azafluorene, we obtained a C₉ furfurylidene product, substituted tetrahydroindine[1,2-b]pyridine and NH-indine[1,2-b]-pyridine. We obtained 7-nitro-1-methyl-4azafluorene by nitration of onychine and oxidation of nitro-substituted azafluorene; this indicates an identical orientation of 4-azafluoren(one) and fluoren(one) during nitration.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 513–517, April, 1982.     

Five-membered 2,3-dioxo heterocycles: LXXXIX. Reaction of methyl 1-aryl-3-cinnamoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates with (E)-4-arylaminopent-3-en-2-ones. Crystalline and molecular structure of 9-acetyl-4-cinnamoyl-3-hydroxy-1-(4-methoxyphenyl)-8-methyl-7-phenyl-1,7-diazaspiro[4.4]nona-3,8-diene-2,6-dione

Methyl 1-aryl-3-cinnamoyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with 4-benzylamino- and 4-arylaminopent-3-en-2-ones to give 1-aryl-7-benzyl- and 1,7-diaryl-9-acetyl-4-cinnamoyl-3-hydroxy-8-methyl-1,7-diazaspiro[4.4]nona-3,8-diene-2,6-diones. The crystalline and molecular structures of 9-acetyl-4-cinnamoyl-3-hydroxy-1-(4-methoxyphenyl)-8-methyl-7-phenyl-1,7-diazaspiro[4.4]nona-3,8-diene-2,6-dione were studied by X-ray analysis.     

Reaction of benzoyl and trichloroacetyl isocyanates with Schiff bases

Conclusions Benzalbenzylamine and p-substituted benzalbenzylamines react with benzoyl and trichloroacetyl isocyanates by the type of 1,4-addition, with the formation of 2,6-diphenyl-3-benzyl-3,4-dihydro-2H-1-oxa-3, 5-diazin-4-one and 2-phenyl-3-benzyl-6-trichloromethyl3,4-dihydro-2H-1-oxa-3,5-diazin-4-one derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 617–621, March, 1970.     

Synthesis of N6-substituted adenines from 3-methylxanthine

A series of 6-arylalkyl(hetarylalkyl, cycloalkyl, carboxyalkyl)amino-7-benzyl-2-chloropurines have been synthesized from 3-methylxanthine via the reaction of the intermediate 7-benzyl-2,6-dichloropurine with amines and aminoacids. N⁶-benzyladenine, N⁶-(-furfuryl)adenine (kinetin), and N-(purinyl)glycine have been obtained via the catalytic hydrogenation of 7-benzyl-6-benzyl(furfuryl, carboxymethyl)amino-2-chloropurines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, 529–532, April, 2000.     

Substituted pyridines 5-methyl-4-benzyl-2-styryl(phenylethynyl)pyridines

5-Methyl-4-benzyl-2-styrylpyridine (II), its p-dimethylaminostyryl analog IV, and 5-methyl-4-benzyl-2-(1,3-dioxo-2-hydrindenyl)pyridine (V) have been prepared. II has been converted into 5-methyl-4-benzyl-2-phenylethynylpyridine (VII), 5-methyl-4-benzylpyridine-2-carboxylic acid (VIII), and 3-styryl-6, 7-benzoisoquinoline (X).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1228–1231, September, 1970.     

Reaction of methyl-substituted pyrylium salts with tertiary amines

2,4,6-Trimethylpyrylium perchlorate reacts with heterocyclic compounds containing apyridine nitrogen atom and having basicities higher than 9 pK_a units (in acetonitrile) through a step involving the formation of a methylenepyran. 4-Methyl-2,6-diphenyl- and 2-methyl-4,6-diphenylpyrylium perchlorates react with benzimidazole to give 1,2-ethanediylidenebispyrans. Methyl-substituted pyrylium salts react with 2,6-diphenylpyrylium and flavylium perchlorates in the presence of benzimidazole to give methylidynecyanines and with acetic anhydride to give trimethylidynecyanines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1484–1489, November, 1976.