Nucleophilic substitution in dibenz[b,d]iodolium and 11,12-dihydro-10H-dibenz[b,g]iodocinium cations

Treatment of dibenz[b,d]iodolium tetrafluoroborate with NO₂ ^–, Br^–, and N₃ ^– ions gave, along with nucleophilic substitution products, 2-nitro-, 2-bromo-, and 2-azido-2-iodiphenyls, diphenyl, 2-iododiphenyl, and 2,2-diiododiphenyl (products of one electron reduction), whereas 11,12-dihydro-10H-dibenz[b,g]iodocinium tetrafluoroborate underwent nucleophilic substitution with all three nucleophiles to give a single product in each case: 1-(2-nitrophenyl)-, 1-(2-bromophenyl)-, or 1-(2-azidophenyl)-3-(2-iodophenyl)propane.M. V. Lomonosov Moscow State University, Moscow 119899. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 405–412, March, 1998.     

Nucleophilic substitution in the 10,11-dihydrodibenz[b,f]iodepinium cation

10,11-Dihydrodibenz[b,f]iodepinium tetrafluoroborate gave only 1-(2-azidophenyl)-2-(2-iodophenylethane with the N₃ ^– in aqueous DMSO, while with NO₂ ^– it gave 1-(2-nitrophenyl)-2-(2-iodophenyl)ethane (93%), 9,10-dihydrophenanthrene (5%), and traces of phenanthrene. Both in pure and aqueous DMSO this cation with the Br^– ion was converted into phenanthrene (80% and 68% respectively) and 1-(2-bromophenyl)-2-(2-iodophenyl)ethane (10 and 20%), while in water it gave 9,10-dihydrophenanthrene (75%) and phenanthrene (5%). A new route for the synthesis of 1-(2-aminophenyl)-2-phenylethane starting from this tetrafluoroborate has been proposed.M. V. Lomonosov Moscow State University, Moscow 119899, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, 110–115, January, 1999.     

Synthesis of anthra[9,1-cd]isothiazolium derivatives and their reactions with nucleophiles

The methylation of 9-methyl-4-methylamino-5H-anthra[1,9,8-bcde]-1,10⁴-dithia-9-azapentalen-5-one takes place at the S₍₁₎, atom and leads to a 2-methyl-7-methylamino-10-methylthio-6-oxo-6H-anthra[9,1-cd]isothiazolium salt, while protonation is directed to the N₍₉₎ atom to give a 5,10-bis(methylamino)-6-oxo-6H-anthra [1,9-cd]dithiolium salt. Depending on their nature, substitution of the hydrogen atom in the 5 or 3 position, reversible addition of a hydroxide ion in the 10b position, demethylation, or opening of the heteroring occurs in the reaction of the anthraisothiazolium cation with nucleophilic reagents.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 256–263, February, 1992.     

Polyfuryl(aryl)alkanes and their derivatives. 7. New recyclization and cyclization reactions in the 2-hydroxyaryldifurylmethane series

Reaction of 2-hydroxybenzaldehydes with -methylfuran (sylvan) under acid-catalysis conditions was investigated. It is shown that the reaction does not stop at the step involving formation of 2-hydroxyarylfuryl-methanes but proceeds further with opening of one of furan rings and recyclization to 3-furylbenzo-furan derivatives. The latter in turn undergo transformations that lead to new heterocyclic systems — 5,6-dihydro-2,4-dimethyl-4-(5-methyl-2-furyl)-4H-benzo[b]furo[2,3-h]cyclopenta[b]furans. Data from the IR, PMR, and mass spectra, alternative synthesis, and x-ray diffraction analysis were used to confirm structures of the synthesized compounds.For Communication 6 see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 616–626, May, 1993.     

Synthesis of pyrazolo[1,5-a]-pyrimidines by reaction of 3,5-diamino-4-nitropyrazole with acetoacetic ester in the presence of alkaline agents

Two major compounds are formed in the reaction of 3,5-diamino-4-nitropyrazole with acetoacetic ester: 2-amino-5-methyl-3-nitro-4,7-dihydropyrazolo[1,5-a]pyrimidin-7-one and 3-amino-5-(-hydroxycrotonyl)amino-4-nitropyrazole. The latter is converted to bicyclic dihydropyrazolo[1,5-a]-pyrimidinone in solutions with heating.State Science Center of the Russian Federation NIOPIK (Scientific Research Institute of Organic Intermediates and Dyes), Moscow 103787Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 73–77, January, 2000.     

Carbolines

The synthesis of 1-methyl-4-(-dimethylaminopropyl)--carboline from 3-(1-methyl-2-pyrrolidyl)indole is described.See [1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 337–339, March, 1973.     

Condensed imidazo-1,2,4-azines. 4. Synthesis of 1,4-Dihydroimidazo[1,5-c]-1,2,4-triazine derivatives

The reaction of 2-methyl-4(5)-nitro- and 2-methyl-4(5)-nitro-5(4)-bromoimidazoles with -halo ketones was investigated, during which a number of 1-acylmethyl-substituted 2-methyl-4-nitro- and 2-methyl-4-nitro-5-bromoimidazoles were obtained. 1,4-Dihydro derivatives of imidazo[1,5-c]-1,2,4-triazine were synthesized by reaction of the latter with hydrazine and its monosubstituted derivatives. The structures of the 1-acylmethyl-substituted 2-methyl-4-nitro-5-bromoimidazoles and 1,4-dihydro derivatives of imidazo[1,5-c]-1,2,4-triazine were confirmed by their IR, PMR, and mass spectra.See [1–3] for Communications 1–3, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 833–837, June, 1981.     

Synthesis of 6-methyl-3-cyano-5-ethylpyridine-2(IH)thione and condensed heterocycles based on this compound

Summary It has been established that the direction of formylation of methyl propyl ketone depends on the reaction conditions. By condensation of the synthesized salts of 3-hydroxymethylene-2 pentanone with cyanothioacetamide, we have synthesized 6-methyl-3-cyano-5-ethylpyridine-2(1H)-thione and 6 propyl-3cyancpyridine-2(IH)-thione, respectively, which are alkylated regioselectively by halides ClCH₂Z (Z = Alk, COOAlk, COPh, CONH₂, CN) at the sulfur atom. These thiones and the derived 2-SCH₂Z-3-cyanopyridines have been used in the regioselective synthesis of substituted annelated heterocycles: 3-aminothieno(2, 3b]pyridines and 4-aminopyridol[2,3:2,3]thieno[4,5-d]pyrimidines. 3:2, 3]thieno[4, 5-d]pyrimidines.N. D. Zelinski Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, 117913. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 851–857, June, 1995. Original article submitted May 22, 1995.     

Synthesis of 2,3-dioxo-2,3-dihydro-4-methyl-6-chloro-1H-pyrrolo[2,3-b]pyridine and its 1-α-L-arabinopyranoside

A new type of isatin analog-2,3-dioxo-2,3-dihydro-4-methyl-6-chloro-1H-pyrrolo[2,3-b]pyridine — was obtained by oxidation of 4-methyl-6-chloro-1H-pyrrolo(2,3-b]pyridine. Condensation of L-arabinose with 4-methyl-6-chloro-2,3-dihydropyrrolo[2,3-b]pyridine and subsequent acetylation and dehydrogenation gave 1-(2,3,4-tri-O-acetyl--L-arabinopyranosyl)-4-methyl-6-chloropyrrolo[2,3-b]pyridine, which served as the starting compound for the synthesis of 1--L-arabinopyranosyl-4-methyl-6-chloropyrrolo[2,3-b]pyridine. Oxidation of 1-(2,3,4-tri-O-acetyl-L-arabinopyranosyl)-4-methyl-6-chloropyrrolo[2,3-b]pyridine gave 1-(2,3.4-tri-O-acetyl--L-arabinopyranosyl)-2,3-dioxo-2,3-dihydro-4-methyl-6-chloropyrrolo [2,3-b]pyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1083–1086, August, 1977.     

Solid-phase synthesis of 1,2-benzophenazine and some fused imidazole derivatives

The solid-phase synthesis of 1,2-benzophenazine and various N-methylbenzimidazoles using o-diaminoarenes is very promising and permits the synthesis of 1-methyl-4,5-[b]naphtho-1H-imidazole, which could not be obtained by the condensation of o-diaminoarenes with paraformaldehyde using the standard liquid-phase method.M. V. Lomonosov Moscow State University, 119899, Moscow, Institute for Synthetic Polymer Materials, 117461, Moscow, and Institute of Physiologically Active Compounds, Russian Academy of Sciences, Chernogolovka, 1424432, Moscow Oblast. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 672–674, May, 1996. Original article submitted April 3, 1996.     

E.p.r. evidence for the formation of the six-coordinate pentafluoronitridotechnetate(VI) anion in solution

The reaction of AsPh4[TcNX4] (X=Cl or Br) with naked F– in MeCN solution has been shown by e.p.r. spectroscopy to result in the facile substitution of the halo ligands by fluoride. Addition of six equivalents of NBu4F·3H2O has provided, for the first time, direct evidence for the formation of the six-coordinate [TcNF5]2– in solution. An e.p.r. study of ligand exchange of Cs2[TcNCl5] (4 × 10–2 – 5 × 10–4 mol dm–3) in 28.6 mol dm–3 aqueous HF has shown that the distribution of the five [TcNFnCl4–n]– (n = ;0–4) species is concentration dependent, with the formation of [TcNF4]– being favoured by dilution.     

Chemistry of indole

The condensation of salts of 1-methyl-2-aminoindole with aldehydes in excess alkali gives Schiff bases, while salts of 1-methyl-3-arylidene-2-iminoindolines are obtained in the absence of alkali. The latter may give 12-aryl-5,7-dimethylindolo[2,3-b]--carbolines (I) on reaction with excess 1-methyl-2-aminoindole. Dihydro compounds (II) are formed as intermediates.See [1] for communication XXXI.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1368–1373, October, 1972.     

Synthesis of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines. 7. 7-(β-d-ribofuranosyl)-4-methylthioimidazo[4,5-d]-1,2,3-triazine

The synthesis of 7-(-D-ribofuranosyl)-4-methylthioimidazo[4,5-d]-1,2,3-triazine, 7-methyl-4-methylthioimidazo[4,5-d]-1,2,3-triazine, and 5-methyl-4-methylthioimidazo [4,5-d]-1,2,3-triazine is described. The structures of the synthesized compounds were confirmed by ¹³C NMR spectroscopy.See [1] for communication 6.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 836–838, June, 1979.     

Synthesis of 2-amino-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]selenophene and some transformations based on it

A new method for the synthesis of 2-amino-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]selenophene was developed. The reaction of the latter with allyl isothiocyanate gave 2-(N-allylthioureido)-3-carbethoxy-4,5,6,7-tetrahydrobenzo[b]selenophene, which is cyclized to the potassium salt of 3-allyl-4-oxo-2-thio-3,4,5,6,7,8-hexahydrobenzo[b]selenopheno[2,3-d]pyrimidine on treatment with potassium hydroxide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 326–328, March, 1973.     

α-Oxides in reaction with N-H acids of the heterocyclic series

Anumber of 1-methyl-4-(2-hydroxyalkyl)-3-nitro-1,2,4-triazol-5-ones and their derivatives were obtained by reaction of 1-methyl-3-nitro1,2,4-triazol-5-one with -epoxides. The fact of intramolecular nucleophilic substitution of the nitro group in hydroxy derivatives of 3-nitro-1,2,4-triazol-5-one with cyclization to 2-methyl-3-oxo-5,6-dihydrooxazolo[3,2-b]-1,2,4-triazoline was established.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1407–1410, October, 1977.     

New simple laboratory method for the synthesis of pirazidol

5,6-Dihydro-8-methyl-4H-pyrazino[3,2,1-j,k]carbazole was obtained by the reaction of -bromoacetaldehyde dibutylacetal, ammonium acetate, and 1,2,3,4-tetrahydro-6-methyl-1-ketocarbazole in acetic acid. The reduction of 5,6-dihydro-8-methyl-4H-pyrazino[3,2,1-j,k]carbazole or its hydrochloride with sodium borohydride leads to 2,3,3a,4,5,6-hexahydro-8-methyl-1H-pyrazino[3,2,1-j,k]carbazole hydrochloride — the medicinal preparation pirazidol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1362–1363, October, 1983.     

Oxidative reactions of azines. 2.* Synthesis and molecular structure of 3,4-dihydroxy-1-methyl-2-oxo-4-(γ-pyridyl)piperidine

The oxidative ketodihydroxylation of a 1,2,3,6-tetrahydropyridine is reported. Using PMR and x-ray structured analysis, the product was shown to be 3,4-dihydroxy-1-methyl-2-oxo-4-(-pyridyl)piperidine.For communications 1, see [1].Russian University of National Friendship, Moscow 117198. L. Ya. Karpov Physicochemical Science Research Institute, Moscow 103603. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1372–1375, October, 1996. Original article submitted June 20, 1996.     

Stereochemistry of Nitrogen Heterocycles. Transformations of Stereoisomeric 1-chloro-2-methyl-4-keto-trans-decahydroquinolines in an acidic medium

It is shown that epimeric [with respect to the C(₂) atom] 1-chloro-2-methyl-4-keto-trans-decahydroquinolines in an acidic medium undergo intermolecular monochlorination in the position relatve to the carbonyl group with the formation of epimeric [with respect to the C(₂) atom] 3e-chloro- and 10a-chloro-2-methyl-4-keto-trans-decahydroquinolines and 2-methyl-4-keto-10-chloro-cis-decahydroquinolines. The mechanism of the transformations is examined, and an assumption regarding the possibility of cis-trans isomerization of the intermediately formed -chloronium complex is expressed.See [1] for Communication 66.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1100–1108, August, 1988.     

Synthesis of an analogue of the phospholipid platelet activation factor from a natural ethanolamine plasmalogen

The synthesis has been performed of an analogue of the phospholipid platelet activation factor — 1-0-(alk-1-enyl)-2-acetyl-sn-glycero-3-phospho-N-(N-acetylglycylethanolamine). In concentrations of 10^–7-10^–6 M, the analogues so obtained inhibited the aggregation of human platelets stimulated by the phospholipid activation factor.Scientific-Research Institute of Biomedical Technology, USSR Ministry of Health, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 325–330, May–June, 1990.     

Introduction of substituents in the pyridine proton of 7-azaindoline

Electropilic substitution (nitration, bromination, and chlorination) of 4-methyl-6-chloro-7-azaindoline (and its N-acetyl derivative) takes place in the 5 position. 4-Methyl-5-amino-7-azaindoline, 4-methyl-5-nitro-7-azaindoline, and 1-acetyl-4-methyl-5-amino-6-chloro-7-azaindoline were obtained by reduction of 1-acetyl-4-methyl-5-nitro-6-chloro-7-azaindoline under various conditions. A method was developed for the preparation of a new three-ring system — 1,2,3-oxadiazolo[5,4-b]-pyrrolo[2,3-e]pyridine.Communication L from the series Derivatives of Azaindoles. See [1] for communication XLIX.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 380–384, March, 1977.