Synthesis,Characterization, and Antimicrobial Studies of Some Quinolines Containing 1,3-Thiazines

6/8-Substituted-2-chloroquinoline-3-carboxylic acids, upon reaction with 3-(p-substituted aryl)-4H-5-mercapto-1,2,4-triazoles in the presence of sodium acetate and an acetic anhydride medium, afforded a novel series of 2-(p-substituted aryl)-s-triazolo[5,1-b]-6/8-substituted quinolino [1,3] thiazin-9(H)-ones. The structures of the new compounds were elucidated by IR, ¹H NMR, and mass spectral studies. All the newly synthesized compounds have been screened for their antibacterial and antifungal activities. Most of them showed significant activity comparable with that of the standards Furacin and Flucanazol.     

Condensed isoquinolines. 37.* Heterocyclization using 3-(arylamino)- and 3-(hetarylamino)isoquinolin-1(2H)-ones

The reaction of 3-NHR-isoquinolin-1(2H)-ones (R = Ar) with aromatic aldehydes in the presence of Me3SiCl or in acetic acid leads to the formation of derivatives of dibenzo[b,f][1, 8]naphthyridin-5(6H)- one and benzo[f]isoquino[3,4-b][1, 8]naphthyridine-5,9(6H,7H)-dione. The reaction for R = Het in the presence of Me3SiCl gives derivatives of 5H-pyrido[1',2':1,2]pyrimido[4,5-c]isoquinolin-5-one, benzo[f]isoquinoline[3,4-b][1,8]naphthyridine-5,9[6H,7H]-dione, and derivatives of new heterocyclic systems, 5H-pyrazino[1',2':1,2]pyrimido[4,5-c]isoquinolin-5-one, 5H-[1,3]thiazolo[3',2':1,2]pyrimido- [4,5-c]isoquinolin-5-one, 5-H-benzo[f]pyrazolo[3,4-b][1,8]naphthyridin-5-one, and isoquino[3,4-b]- [1,5]naphthyridin-5(6H)-one. The effect of the structure of substituent R and nature of the substituent in the benzaldehydes on the structure of the reaction products was studied.     

PIFA-promoted intramolecular oxidative C(aryl)-H amidation reaction: Synthesis of quinolino[3,4-b]quinoxalin-6(5H)-ones

A facile and direct intramolecular oxidative C(aryl)-H amidation reaction was developed for the synthesis of quinolino[3,4-b]quinoxalin-6(5H)-ones in moderate to excellent yields starting from readily available materials by tethering the adjacent N-methoxyamide and aryl portions in the presence of phenyliodine(III) bis(trifluoroacetate) at room temperature. This metal-free approach is a valuable addition to the traditional methods already available for the preparation of these molecules.     

Synthesis of New 2-(6H-Indolo[2,3-b]quinoxalin-6-yl)-1-phenylethane-1-ones

Russian Journal of General Chemistry - A series of new 2-(6H-indolo[2,3-b]quinoxalin-6-yl)-1-phenylethan-1-ones was synthesized by the reaction of various 6H-indolo[2,3-b]quinoxalines with...     

Five-membered 2,3-dioxoheterocycles: LXXIII. Synthesis and thermolysis of 3-acylpyrrolo[1,2-a]quinoxaline-1,2,4(5H)-triones

Reactions of (Z)-3-(phenacylidene-2-oxo)-3,4-dihydroquinoxalin-2(1H)-ones and (Z)-3-(3,3-dimethyl-2-oxobutylidene)-3,4-dihydroquinoxalin-2(1H)-one with oxalyl chloride led to the formation of 3-acyl-1Hpyrrolo[1,2-a]quinoxaline-1,2,4(5H)-triones that at the thermal decarbonylation generated acyl(3-oxoquinoxalin-2-yl)ketenes which underwent the intramolecular stabilization giving 3-acylfuro[3,2-b]quinoxalin-2(4H)-ones.     

Synthesis of some new spiroindoline derivatives incorporated with pyrazoloheterocycles

Indole-2,3-dione ( 1 ) was treated with malonic acid ( 2 ) in a mixture of ethanol/pyridine to afford 1-[3-(2-oxoindolinylidene)]acetic acid ( 3 ). Compound 3 reacted with thionyl chloride to give the corresponding acid chloride ( 4 ). The acid chloride 4 reacted with arenes in the presence of AlCl₃ to yield 3-(2-oxoindolinylidene)acetophenones 5a–c . Compounds 5a–c reacted with 3-methylpyrazolin-5-one derivatives 6a , b to give 3-aracyl-3-[4′-(3′-methylpyrazolin-5-onyl)]-indoline-2-one derivatives 7a–f . Compounds 7a–f were treated with phosphorus pentoxide in phosphoric acid, with ammonium acetate or methanolic methylamine and with phosphorus pentasulfide to give spiro[indoline-3,4′-(pyrazolo[4,5-b]pyran)]-2-ones 8a–f , spiro[indoline-3,4′-(pyrazolo[4,5-b]-dihydropyridine)]-2-ones 9a–f , 10a–f and spiro[indoline-3,4′-(pyrazolo[4,5-b]thiopyran)]-2-ones 10a–f , respectively. All of the synthesized spiroheterocycle derivatives were identified by conventional spectroscopic methods (IR, ¹H NMR) and elemental analyses. © John Wiley & Sons, Inc.     

Imidazo[1,5-a]- and Thiazolo[3,4-a]quinoxalines Based on 3-(a-Thiocyanobenzyl)quinoxalin-2(1H)-one

When 3-(a-thiocyanobenzyl-2(1H)-one is heated, competing processes of [a]-annelation of the imidazole or thiazole rings occurs with formation of imidazo[1,5-a]- and thiazolo[3,4-a]quinoxalin-4(5H)-ones.     

Condensed isoquinolines 23. Reaction of <Emphasis Type="Italic">o</Emphasis>-bromomethylphenyl-acetonitrile with anthranilic acids: Synthesis of 6H, 12H,17H-dibenzo[3,4:6,7][1,8]-naphthyridino[1,8-<Emphasis Type="Italic">ab</Emphasis>]quinazoline-6,17-diones

The direction of the reaction of anthranilic acids with o-bromomethylphenylacetonitrile upon fusion depends on the temperature and nature of the substituent in the anthranilic acid. The reaction may lead to three types of products: Derivatives of 7,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-ones below 150°C and to 6,11-dihydro-13H-isoquino[3,2-b]quinazolin-13-one or derivatives of 6H,12H,17H-dibenzo[3,4:6,7][1,8]naphthyridino[1,8-ab]quinazoline-6,17-diones above 150°C depending on the nature of the substituent in the anthranilic acid. A study was carried out on the mechanism for the formation of 6H,12H,17H-dibenzo[3,4:6,7][1,8]naphthyridino[1,8-ab]quinazoline-6,17-diones, which permitted the preparation of 6-(4-methylphenyl)-6,12-dihydro-5H-isoquino[2,3-a]quinazolin-5-one. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1059–1067, July, 2007.     

Non-catalytic approach to the synthesis of partially reduced 'S' shaped dioxathia- and oxadithiahelicenes through base induced inter- and intramolecular C-C bond formation

An efficient and convenient route for the construction of helical 'S' shaped dioxathia- and oxadithiahelicenes with oxygen and sulfur atoms located in the middle of the outer helix has been developed through base induced inter- and intramolecular C-C bond formation from the reaction of 4-sec-amino-2-oxo-2,5-dihydrothiochromeno[4,3-b]pyran-3-carbonitriles with 3,4-dihydro-2H-benzo[b]oxepin-5(2H)-ones, 3,4-dihydrobenzo[b]thiepin-5(2H)-one and thiochroman-4-ones separately. Quantum chemical calculations have also been carried out to explore the geometries and electronic structures of newly synthesized compounds to envisage the pathway for interconversion of both atropisomers. The determination of helicity parameters and configurational stability demonstrate that the energy barrier is strongly dependent on the nature of hetero-atoms present.     

Unusual reactions of 5,5-dimethyl-2-(indenyl-2)-3-pyrazolidinone with acetylenedicarboxylates

[reaction: see text] Reaction of 5,5-dimethyl-3-pyrazolidinone (1) with 2-indanone (2) gave 5,5-dimethyl-2-(1H-indenyl-2)-3-pyrazolidinone (3) instead of the expected azomethine imine 4. Although reaction of 2-substituted 3-pyrazolidinones with acetylenedicarboxylates usually gives ring expansion products, such as 1,2-diazepines, treatment of 3 with dialkyl acetylenedicarboxylates (5, R = Me; 6 R = Et) resulted in the formation of rel-(7aR,12aS)-6,7-bis(alkoxycarbonyl)-3,4-dihydro-4,4-dimethyl-7aH-indano[1,2-b]pyrrolo[1,2-a]pyrimidin-2-ones (7, R = Me; 9, R = Et) as major products and 3,4-bis(alkoxycarbonyl)-7,7-dimethyl-2-(indenyl-2)-6,7-dihydro-2H,6H-1,2-diazepin-5-ones (8, R = Me: 10, R = Et) as minor products.     

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.     

Alkaloids ofNitraria komarovii. VI. Structure and synthesis of isokomarovine and of komarovidinine

Two new alkaloids, isokomarovine and komarovidinine, have been isolated from the epigeal part of the plantNitraria komarovii Iljin et Lava. The passage from isokomarovine to komarovidinine has been performed. Their structures have been established on the basis of spectra and experimental facts: 1-(quinolin-5′-yl)-9H-pyrido[3,4-b]indole and indolo[3,2,1-de]quinolino[4,5-gh][1,5]naphthyridine, respectively. Their synthesis has been performed.     

3 + 2] Cycloaddition reactions in the synthesis of triazolo[4,5-b]pyridin-5-ones and pyrrolo[3,4-b]pyridin-2-ones

The reaction of 5-benzenesulfonyl-3,4-dihydro-1 H-pyridin-2-one derivatives with azides or isocyanides provided two new classes of compounds, triazolo[4,5-b]pyridin-5-ones 3 or pyrrolo[3,4-b]pyridin-2-ones 4, respectively, in good yields and regioselectivity. A representative set of 20 compound 3 and 12 compound 4 was prepared.     

Exploiting the divergent reactivity of α-isocyanoacetate: multicomponent synthesis of 5-alkoxyoxazoles and related heterocycles

A novel multicomponent synthesis of 5-alkoxyoxazoles, based on a new reactivity profile of α-isocyanoacetates, is described. Thus, simply heating a solution of amine, aldehyde, and α-(EWG-phenyl)-α-isocyanoacetate or α-(4-pyridyl)-α-isocyanoacetate (EWG=electron-withdrawing group) in toluene provided 5-alkoxyoxazoles in good to excellent yields. Reaction of the 5-alkoxyoxazoles with various α,β-unsaturated acyl chlorides led to the formation of epoxytetrahydropyrrolo[3,4-b]pyridin-5-ones by a domino N-acylation/Diels-Alder cycloaddition sequence. Subsequent fragmentation under basic conditions provided 6,7-dihydro-5H-pyrrolo[3,4-b]pyridin-5-ones. A four-component synthesis of the pyridin-5-one compounds, without isolation of the 5-alkoxyoxazole, was subsequently developed.     

Environmentally friendly and efficient method for the synthesis of the new α,α′-diimine ligands with benzimidazole moiety

The new α,α′-diimine ligands with benzimidazole moiety were synthesized based on the rearrangement of 3-aroylquinoxalin-2(1H)-ones when exposed to 4,5-diamino-2,1,3-benzoxadiazole, 4,5-diamino-2,1,3-benzothiadiazole and 5,6-diaminoquinoxaline. Among them, we report the first examples of the new heterocyclic system namely benzo[4′,5′]imidazo[1′,2′:1,2]quinolino[3,4-b and 4,3-b][1,2,5]oxadiazolo[3,4-f]quinoxalines, which exhibits an interesting electrochemical behavior. All compounds were fully characterized by IR, ¹H and ¹³C NMR spectroscopies, and mass spectrometry.     

Synthesis of dihydrodiol metabolites implicated in the mechanism of carcinogenesis of phenanthro[4,3-b][1]benzothiophene and phenanthro[3,4-b][1]benzothiophene,the polycyclic sulfur heterocycles with a "Fjord" structure

Dihydrodiols, which are potential proximate carcinogens of phenanthro[4,3-b][1]benzothiophene (3) and phenanthro[3,4-b][1]benzothiophene (4) and possess a "fjord" structure, were synthesized. The dihydrodiols synthesized were trans-3,4-dihydroxy-3,4-dihydrophenanthro[4,3-b][1]benzothiophene (5) and trans-3,4-dihydroxy-3,4-dihydrophenanthro[3,4-b][1]benzothiophene (6). The precursors to the dihydrodiols 5 and 6 were 3-methoxyphenanthro[4,3-b][1]benzothiophene (11) and 3-methoxyphenanthro[3,4-b][1]benzothiophene (16). Compound 11 was obtained via Suzuki cross-coupling reaction of easily accessible starting materials. However, this synthetic strategy utilizing Suzuki reaction for the preparation of 16 was comparatively less productive than that described previously due to time-consuming synthesis of the starting material(s), and extremely poor yield associated with cyclization of the epoxide 15 to 16. The methoxy derivatives 11 and 16 were converted to the corresponding dihydrodiols 5 and 6 by a sequence involving demethylation, oxidation, and reduction. The trans-stereochemistry of the dihydrodiols was established by (1)H NMR, which indicated a large coupling constant between vicinal carbinol protons. The UV spectra of the dihydrodiols 5 and 6 are presented.     

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.     

Reaction of indoles with aldehydes. Synthesis of dihydropyrrolo[3,4-b]indoles

Aromatic aldehydes react with amides of 1-methylindole-2-carboxylic acid under acid catalysis conditions to give 1-aryl-4-methyldihydropyrrolo[3,4-b]indol-3-ones. The intermediate 1-methyl-2-CONHR-3(-X-benzyl)indoles, which are subsequently converted to the indicated cyclic compounds, were isolated. o-Acetyl derivatives were obtained by the action of acetic anhydride on derivatives of unsubstituted amides. Dihydropyrrolo[3,4-b] indol-3-ones were reduced by LiAlH₄ to the corresponding dihydropyrrolo[3,4-b] indoles. A mechanism for the formation of dihydropyrrolo[3,4-b] indoles is proposed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1516–1523, November, 1976.     

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.     

The Pictet-Spengler reaction in the synthesis of condensed benzodiazepines 1. synthesis of 6,11,12,14-tetrahydrobenzo-[4,5][1,2]diazepino[7,1-b]quinazolin-14-ones

A new strategy is proposed for the synthesis of the seven-membered heterocyclic skeleton of tetrahydro[4,5][1,2]diazepino[7,1-b]quinazolin-14-ones based on the Pictet-Spengler reaction of 3-amino-2-(3,4-dimethoxybenzyl)quinazolin-4(3H)-one with aromatic aldehydes and paraform in acid media.