Halocyclization of 3-allylthio-5H-[1,2,4]triazino[5,6-<Emphasis Type="Italic">b</Emphasis>]indole

The synthesis of 3-allylthio-5H-[1,2,4]triazino[5,6-b]indole has been carried out by the reaction of 3-mercapto-5H-[1,2,4]triazino[5,6-b]indole with allyl bromide in the NaOH–H₂O–DMSO system and in a one-pot synthesis from isatin-β-thiosemicarbazide. Halocyclization of allylthio-5H-[1,2,4]-triazino[5,6-b]indole synthesized the 3-halomethyl-3,10-dihydro-2H-[1,3]thiazolo[3',2':2,3][1,2,4]-triazino[5,6-b]indolium halides.     

Condensed isoquinolines 26. Oxidation reactions of 6,11-dihydro-13H-isoquino-[3,2-<Emphasis Type="Italic">b</Emphasis>]quinazolin-13-one derivatives

Oxidation of the hydrobromide of 6,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-one with dimethyl sulfoxide leads to 11-hydroxy-11H-isoquino[3,2-b]quinazoline-6,13-dione, and with hydrogen peroxide to the hydrobromide of 2-[(4-oxo-3,4-dihydro-2-quinazolinyl)carbonyl]benzoic acid. Salts of 5-and 6-alkyl-substituted isoquino[3,2-b]quinazolines are readily oxidized on boiling in nitrobenzene, which leads to aromatization of the isoquino[3,2-b]quinazoline system to 5-methyl-13-oxo-5H,13H-isoquino[ 3,2-b]quinazolinium perchlorate and 6-benzyl-13H-isoquino[3,2-b]quinazolin-13-one. The structures of the dehydrogenation products were established from ¹H NMR and UV spectra. The interaction of the obtained compounds with NaBH₄ has been studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1833–1840, December, 2007.     

Synthesis of Some New Fused and Polyfused [1,2,4]Triazolo-[3,4-<Emphasis Type="Italic">b</Emphasis>][1,3,4]thiadiazepines

7-[1,3-Dithiolan-2-ylidene]-3-phenyl-5,6,7,8-tetrahydro[1,2,4]triazolo[3,4-b][1,3,4]thiadiazepine-6,8-dione and 7-[5-oxo-1,3-dithiolan-2-ylidene]-3-phenyl-5,6,7,8-tetrahydro[1,2,4]triazolo[3,4-b][1,3,4]-thiadiazepine-6,8-diones were obtained by treating 3-phenyl-5,6,7,8-tetrahydro[1,2,4]triazolo-[3,4-b][1,3,4]thiadiazepine-6,8-diones with CS₂ and chloroacetyl chloride, respectively. Treatment of the above compounds with mercaptoacetic acid gave 1,2-dibromoethane or the corresponding spiro polyfused heterocycles. Some other triazolothiadiazepine derivatives including spiro polyfused compounds were also synthesized. __________ Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 8, 1256–1264, August, 2005.     

Pyridyl-substituted [1,3]Dithiolo-[4,5-<Emphasis Type="Italic">b</Emphasis>][1,4]dithiine-2-thiones

We have obtained 5-(2-pyridyl)[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione for the first time by cycloaddition of 2-ethynylpyridine to 4,5-dihydro-1,3-dithioltrithione (isotrithionedithiol). We have studied this thione, 5-(2-pyridyl)- and 5-(4-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thiones by mass spectroscopy and also IR, UV, ¹H and ¹³C NMR spectra. We have determined the crystal and molecular structure of 5-(2-pyridyl)-5,6-dihydro[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 429–434, March, 2005.     

Condensed isoquinolines. 36*. Cyclization of N-alkyl-3-(2-benzoylbenzyl)azolium salts. A novel method of preparing azolo[<Emphasis Type="Italic">b</Emphasis>]isoquinolines

A novel method is proposed for the preparation of azolo[b]isoquinolines based on the alkylation of N-alkyl-1,3-diazoles or 1,3-thiazole derivatives using [2-(bromomethyl)phenyl](phenyl)methanone with subsequent cyclization of the quaternary azolium salts in the presence of base. The 10(11)-hydroxy derivatives of the 5,10-dihydro-1H-imidazo[1,2-b]isoquinolinium, 6,11-dihydro-5H-benzimidazo-[1,2-b]isoquinolinium, 5,10-dihydro-1H-[1, 2, 4]triazolo[4,3-b]isoquinolinium, or 5,10-dihydro[1, 3]-thiazolo[3,2-b]isoquinolinium bromides obtained in this way readily lose a molecule of water upon heating with HBr or Ac₂O to give the corresponding quasi-aromatic azolo[b]isoquinolinium salts.     

Heterocyclic analogs of 5,12-naphthacenequinone 6. Synthesis of 4,11-dimethoxy derivatives of anthra-[2,3-<Emphasis Type="Italic">b</Emphasis>]thiophene-5,10-dione and anthra[2,3-<Emphasis Type="Italic">d</Emphasis>]isothiazole-5,10-dione

Condensation of 2-formyl-or 2-cyano-3-chloro-1,4-dimethoxyanthraquinone with methyl thioglycolate in the presence of base gave methyl 4,11-dimethoxyanthra[2,3-b]thiophene-5,10-dione-2-carboxylate and its 3-amino derivative respectively. Hydrolysis of the ester group in methyl 4,11-dimethoxyanthra[2,3-b]thiophene-5,10-dione-2-carboxylate and subsequent decarboxylation of the carboxylic acid formed gave 4,11-dimethoxyanthra[2,3-b]thiophene-5,10-dione. Condensation of 3-chloro-2-formyl-1,4-dimethoxyanthraquinone with ammonia in the presence of sulfur gave 4,11-dimethoxyanthra[2,3-d]isothiazole-5,10-dione __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 538–543, April, 2007.     

Recherches en Serie Azabenzodiazepine. III—Fragmentation en Spectrometrie de Masse de Quelques Pyrido,Pyrimido, Pyrazolodiazepinones,Triazino et Triazolotriazepinones

The mass spectra of several pyrido [2,3-b] and [3,4-b], pyrimido [4,5-b], pyrazolo [3,4-b] diazepinones-1,4 and as-triazino [4,3-b], s-triazolo [4,3-b]triazepinones-1,2,4 are reported and analysed. Five different fragmentation pathways of the molecular ion are generally observed, but the main one is an initial loss of CH₂CO which gives rise to 2-methylazabenzimidazole or 2-methyl azabenzotriazole ions. The behaviour of triazolotriazepines which have two further fragmentation pathways is described.     

Condensed isoquinolines 30. Acylation and alkylation of 5,13-dihydro-11H-isoquino-[3,2-<Emphasis Type="Italic">b</Emphasis>]quinazolin-11-one

It was shown that 6-acyl-5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-ones are formed when 5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-one is heated with the chlorides and anhydrides of carboxylic acids in the presence of bases (pyridine, NaOAc) while 5-acyl-5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-ones are formed in the presence of NaH. In the presence of NaH 6-acyl-5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-ones form the products from acylation and alkylation at position 5. The action of heat on 5,13-dihydro-11H-isoquino[3,2-b]quinazolin-11-one in oxalyl chloride leads to 7H,8H-2a,7a-diazacyclopenta[fg]naphthacene-1,2,8-trione. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 741–750, May, 2008.     

5α-androstano [3,2-b]pyridines, 5α-androstano[17,16-b]pyridines and androst-4 and 5-eno[17,16-b]pyridines

A new synthesis of 5α-androstano[3,2-b]pyridin-17β-ol acetate (VIa) and 17-methyl-5α-androstano[3,2-b]pyridin-17β-ol (VIb), first reported by Shimizu, Ohta, Ueno, and Takegoshi, was achieved. The analogous 5α - androstano[17,16-b]pyridin-3β-ol (XII), 5α-androstano[17,16-b]pyridin-3-one (XIVa), and androst-4-eno[17,16-b]pyridin-3-one (XIVb) were also prepared. An illustration of the method follows. Condensation of 3β-hydroxy-5α-androstan-17-one (VIIa) with 3-(2-furyl)acrolein afforded 16-[3-(2-furyl)-2-propenylidene]-3β-hydroxy-5α-androstan-17-one (VIIIa), the oxime (IXa) of which was thermally cyclized to 5α-androstano[17,16-b]-6′-(2-furyl)pyridin-3β-ol (Xa). 3β-Hydroxy-5α-androstano[17,16-b]pyridine-6′-carboxylic acid (XI) was obtained by ozonolysis of Xa. Thermal decarboxylation of XI gave XII. Cinnamaldehyde was used in place of 3-(2-furyl)acrolein to give the corresponding phenylpyridines.     

Synthèse d'analogues furanniques du benzo[a]pyrène

We describe here the synthesis of 2-furan analogues of benzo[a]pyrene from 1-bromo-kpyrene, i.e., pyreno[1,2-b]furan and pyreno[2,1-b]furan, as well as that of their derivatives bearing a nitro group on the heterocycles.     

Condensed isoquinolines 22. Synthesis and properties of 6,11-dihydro-13H-isoquino-[3,2-<Emphasis Type="Italic">b</Emphasis>]quinazolin-13-ones

The reaction of 3-haloanthranilic acids with o-bromomethylphenylacetonitrile gave 2-(2-carboxy-6-halophenyl)-1,4-dihydro-3(2H)-isoquinolinium bromides. 2-Chlorophenylisoquinolinium bromides are readily converted into 4-R-6,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-ones by heating >145°C, but 2,4-dibromophenylisoquinolinium bromide only on fusing with anthranilic acid. The effect of the nature and position of substituents in the quinazoline fragment of 7,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-ones on the rate of the rearrangement into 6,11-dihydro-13H-isoquino[3,2-b]quinazol-13-ones has been studied. The oxidation and borohydride reduction of 6,11-dihydro-13H-isoquino[3,2-b]quinazol-13-ones has been studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, 899–909, June, 2007.     

Synthesis of polyheterocyclic compounds derived from 6-amino- 4-aryl-2-r-4h-furo[2,3-<Emphasis Type="Italic">b</Emphasis>]pyran-5-carbonitriles

Syntheses were developed for 4-aryl-6-ethoxy-2-R-furo[2,3-b]pyridine-5-carbonitriles and ethyl esters of 5-amino-4-aryl-7-methyl-2-R-1,9-dioxa-8-azacyclopenta[b]naphthalene-6-carboxylic acids based on the reaction of 6-amino-4-aryl-2-R-4H-furo[2,3-b]pyran-5-carbonitriles with ethyl acetoacetate and nucleophilic recyclization. The mechanisms of these reactions are considered.     

Condensed isoquinolines 27*. Synthesis and oxidation reactions of 5,13-dihydro-11H-isoquino[3,2-<Emphasis Type="Italic">b</Emphasis>]quinazolin-11-one

Condensation of 2-(cyanomethyl)benzoic acid with 2-aminobenzylamine gave 6,11-dihydro-13H-isoquino[3,2-b]quinazolin-11-one. Its oxidation in nitrobenzene led to the formation of 5,13,5′,13′-hexahydro[6,6′]bi[isoquino[3,2-b]quinazoline]-11,11′-dione, but in dichlorobenzene in the presence of elemental sulfur and iodine it gave the rearrangement product 6H-dibenzo[b,f][1,8]naphthyridin-5-one. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No.2, 273–279, February, 2008.     

Quelques réactions nuclé ophiles et électrophiles de la thiéno[2,3-b]pyrazine. Comparaison de sa réactivite avec celles de thiéno diazines et de la thiényl-2 pyrazine dans le cas de la nitration

We studied the action of nbutyllithium, the action of chlorine and the action of nitric acid in sulfuric acid medium on thieno-[2,3-b]pyrazine, These reactions led us to comparethe behaviour of thieno[2,3-b]pryazine with that of thieno[2,3-d]pyrimidine and of thieny1-2pyrazine under the same consitions.     

Synthèse et étude de modèles de NADH à noyaux accolés en série pyrrolo[2,3-b] et [3,2-b]pyridines

Pyrrolo[2,3-b] and [3,2-b]pyridines derivatives, precursors for annealated NADH models have been prepared. Several methods for building a pyridinic annealates ring have been used starting from 2- or 3-aminopyrrole. The corresponding dihydropyridine structure leads to highly reactive NADH models compounds and are very much more stable than common models.     

A novel synthesis of 2-substituted 2H-imidazo[1,5-<Emphasis Type="Italic">b</Emphasis>]isoquinoline-1,5-diones by <Emphasis Type="Italic">in situ</Emphasis> desulfurization

A novel synthesis of 2-substituted 2H-imidazo[1,5-b]isoquinoline-1,5-diones by reductive desulfurization of a variety of 2-substituted 3-thioxo-2H-imidazo[1,5-b]isoquinoline-1,5-diones is reported with nickel boride in dry methanol at ambient temperature. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 404–408, March, 2008.     

A simple and effective synthetic approach to pyrido[2,1-<Emphasis Type="Italic">b</Emphasis>]thiazines

The reaction of partially hydrogenated 2-pyridinethiols with 1,3-dibromopropane gives substituted pyrido[2,1-b][1,3]thiazines. The structure of 7,9-dicyano-6-oxo-3,4,6,7-tetrahydro-2H-spirocyclohexane-1′,8-pyrido[2,1-b][1,3]thiazine was solved by X-ray diffraction structural analysis. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1428–1433, September, 2007.     

4-(10-Methyl-10H-phenothiazin-3-yl)-1,4-dihydropyridines, 4,5-dihydroindeno[1,2-<Emphasis Type="Italic">b</Emphasis>]-and 5,5-dioxo-4,5-dihydrobenzo-thieno[3,2-<Emphasis Type="Italic">b</Emphasis>]pyridines

Different modifications of the Hantzsch synthesis using 10-methyl-10H-phenothiazine-3-carbaldehyde gave 4-(10-methyl-10H-phenothiazin-3-yl)-substituted 1,4-dihydropyridine-3,5-di-, 5-oxo-4,5-dihydro-1H-indeno[1,2-b]pyridine-, and 5,5-dioxo-4,5-dihydro-1H-5λ⁶-benzo[4,5]thieno[3,2-b]pyridine-3-carboxylic esters. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 280–288, February, 2007.     

Condensed isoquinolines 24. Reaction of 6,11-dihydro-13H-isoquino[3,2-<Emphasis Type="Italic">b</Emphasis>]quinazolin-13-one with carbonyl compounds

The reaction of 6,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-one with carbonyl compounds occurs at the C₍₆₎ and/or N₍₅₎ atoms depending on the nature of the reagent and the conditions. Condensation with aldehydes gives 6-arylidene-6,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-ones. Acylation using acid anhydrides or acid chlorides gave 5-acyl-, 6-acyl-, and 5,6-diacyl-5,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-ones depending again on the reaction conditions. Acylation using chloroacetyl chloride is accompanied by an intramolecular alkylation to give 7H,8H-2a, 7a-diaza-cyclopenta[f,g]naphthacene-1,7(2H)-dione. Phenyl isocyanate gave the derivative containing a CONHPh group at position 6. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1509–1520, October, 2007.     

Synthèse d'analogues furanniques et nitro-2 furanniques du diméthyl-7,12 benzanthracène

A route to 1-formyl-2-hydroxy-9-methylanthracene and 1-formy 1-2-hydroxy-9,10-dimethylanthracene is desribed. These two aldehydes were further converted into mono- or dimethylanthra[2,1-b]furans, besides the corresponding acids and esters, by condensation with ethyl bromoacetate. The related mono- or dimethyl-2-nitroanthra[2,1-b]furans were also prepared by reaction between the above aldehydes and bromonitromethane, followaed by heating in toluene in the presence of p-toluene-sulfonic acid.