Alkylation of pyrimido[5′,4′:5,6]pyrido[3,2-b]indol-4-one derivatives

Alkylation of 11-benzyl-3,11-dihydro-4H-pyrimido[5′,4′:5,6]pyrido[3,2-b]indol-4-one with methyl iodide and methyl bromoacetate in DMF gave 3-alkylpyrimidopyridoindolones as the corresponding salts. The reaction in acetone in the presence of K₂CO₃ yielded 3,6-disubstitution products. Alkylation with DMF dimethyl acetal gave a mixture of the 3- and 6-alkylpyrimidopyridoindol-4-one bases. The structure of 4-oxo-4,6-dihydro-3H-pyrimido-[5′,4′:5,6]pyrido[3,2-b]indol-11-ium chloride (3b) was proved by X-ray diffraction analysis.     

Synthesis of 4′-alkyl-8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-ones

N-Boc-protected 8-azaspiro[bicyclo[3.2.1]octane-3,2′-oxirane] reacted with primary aliphatic amines through opening of the epoxide ring with formation of the corresponding amino alcohols which were converted into N-chloroacetyl derivatives. The latter underwent cyclization to N-Boc-protected 4′-alkyl-8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-ones by the action of sodium hydride in DMF, and subsequent treatment with hydrogen chloride in ethyl acetate afforded 8-azaspiro[bicyclo[3.2.1]octane-3,2′-morpholin]-5′-one hydrochlorides.     

Synthesis of spiro[furo[3,4-b]pyran-4,3′-pyrroles] by reaction of pyrrolediones with malononitrile and tetronic acid

Russian Journal of Organic Chemistry - Substituted ethyl...     

Synthesis of some new dispiro[dipyrano-(2,4′:6,4″)bidithiolo(4,5-b:4′,5′-e)-4,8-benzoquinones]

Summary The one pot reaction of acetylacetone, CS₂, and tetrabromobenzoquinone in a 2:2:1 molar ratio affords 2,6-di-(1-acetyl-2-oxopropylidene)-bidithiolo-(4,5-b:45-e)-4,8-benzoquinone (3) which was allowed to react with some active methylene reagents in a 1:2 molar ratio to give the dispiro derivatives5–11. The reaction is assumed to proceedvia a hydrolysis of the two acetyl groups in compound3 followed by a nucleophilic addition of the active methylene reagents at the two ethylenic bonds and subsequent cyclization.

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Synthese einiger neuer Dispiro[dipyrano(2,4:6,4)bidithiolo(4,5-b:4,5-e)-4,8-benzochinone]

Zusammenfassung Die Eintopfreaktion von Acetylaceton, CS₂ und Tetrabrombenzochinon in einem molaren Verhältnis von 2:2:1 liefert 2,6-Di-(1-acetyl-2-oxopropyliden)-bidithiolo-(4,5-b:4,5-e)-4,8-benzochinon (3), das anschließend mit aktivierten Methylenverbindungen im Verhältnis 1:2 zu den Dispiroverbindungen5–11 umgesetzt wurde. Die Reaktion verläuft offenbar über eine Hydrolyse der beiden Acetylgruppen in Verbindung3, gefolgt von einer nucleophilen Addition der aktiven Methylengruppen an die ethylenischen Doppelbindungen und anschließender Cyclisierung.

     

Three-component condensation of 3-aminothiophene derivatives with isatines and Meldrum’s acid. Synthesis of 2,5′-dioxo-3′-phenyl-5′,6′-dihydro-4′H-spiro[indoline-3,7′-thieno[3,2-b]pyridine]-2′-carboxylic acids

A method for the synthesis of 2,5′-dioxo-3′-phenyl-5′,6′-dihydro-4′H-spiro[indoline-3,7′-thieno[3,2-b]pyridine]-2′-carboxylic acids was elaborated based on the three-component condensation of 3-aminothiophenes, Meldrum’s acid, and isatines.     

A novel three-component method for the synthesis of spiro[chromeno [4′,3′:4,5] pyrimido[1,2-b] indazole-7,3′-indoline]-2′,6(9H)-dione

A green, efficient, and rapid procedure for the synthesis of novel spiro[chromeno[4′,3′:4,5] pyrimido[1,2-b]indazole-7,3′-indoline]-2′,6(9 H)-dione derivatives has been developed by one-pot condensation of 4-hydroxy-2H-chromen-2-one, isatin, and 1H-indazole-3-amine, in the presence of acetic acid in EtOH. This method has the advantages of operational simplicity, and high yield of products via a simple experimental and work-up procedure as compared to the conventional methods. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.     

Novel One-Pot Multicomponent Synthesis of Substituted 2,3-Dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones and Substituted 3-[3-(N′-Benzylidene-hydrazino)-7H-[1,2,4] triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones

A one-pot procedure has been developed for the synthesis of substituted 2,3-dihydro-2-(6-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7H-[1,2,4]triazolo[3,4-b] [1,3,4]thiadiazin-3-yl)phthalazine-1,4-diones by reaction of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and phthalic anhydrides in acetic acid medium. Similarly, a one-pot, three-component synthetic procedure has been developed for substituted 3-[3-(N¹-benzylidene-hydrazino)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-6-yl]-4-hydroxy-6-methyl-pyran-2-ones from 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and various aromatic aldehydes in absolute ethanol and a few drops of glacial acetic acid.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Synthesis of spiro[furan-3,3′-indolin]-2′-ones by PET-catalyzed [3+2] reactions of spiro[indoline-3,2′-oxiran]-2-ones with electron-rich olefins

An efficient procedure for the synthesis of spiro[furan-3,3′-indolin]-2-ones and dispiro[cycloalkane-1,2′-furan-3′,3″-indolin]-2″-ones has been achieved in high yields and stereoselectivity by photoinduced electron transfer-catalyzed [3+2] reactions of substituted spiro[indoline-3,2′-oxiran]-2-ones with olefins. The reactions proceed by ring opening of spiro[indoline-3,2′-oxiran]-2-ones via C_β–O bond cleavage and subsequent cycloaddition with olefins by using 2,4,6-triphenylpyrylium tetarfluoroborate (TPT) as a sensitizer.     

Synthesis,crystal structure,and properties of 2H-4,8-dimethylfuro[2′,3′:5,6]naphtho[1,2-b]pyran-2-one,a novel DNA intercalator

Summary The furonaphthopyrone6, a novel DNA intercalator, was synthesized in two steps (ca. 56% overall yield) starting from naphthopyrone3. The new naphthopyrone derivatives4 and6 were fully characterized and the absorption and fluorescence spectroscopic properties of6 were determined. The dark interactions of furonaphthopyrone1 and6 with DNA have been investigated by a fluorescence quenching technique and their apparentScatchard binding constants were calculated. The crystal structure of6 was determined. The planarity of6 and the geometry of the active double bond between the -pyrone and the furan moieties of6 suggest that furonaphthopyrones are efficient monofunctional DNA intercalators.

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Synthese, Kristallstruktur und Eigenschaften von 2H-4,8-Dimethylfuro[2,3:5,6]naphtho[1,2-b]pyran-2-on, einem neuen DNA-Intercalator

Zusammenfassung Der neue DNA-Intercalator6 wurde, ausgehend vom Naphthopyron3, in zwei Stufen mit einer Gesamtausbeute vonca. 56% hergestellt. Die neuen Naphthopyronderivate4 und6 wurden vollständig charakterisiert; die Absorptions- und Fluoreszenzeigenschaften von6 wurden bestimmt. Die Dunkelwechselwirkungen von1 und6 mit DNA wurden mittels einer Fluoreszenzquenchtechnik untersucht; ihreScatchard-Bindungskonstanten wurden berechnet. Die Kristallstruktur von6 wurde bestimmt. Die Planarität von6 und die Geometrie der aktiven Doppelbindung zwischen dem -Pyron- und dem Furanteil von6 lassen erwarten, daß Furonaphthopyrone effiziente monofunktionelle DNA-Intercalatoren sind.

     

Crystal and molecular structure studies of 1′-Benzyl-8-(4-fluorobenzyl)-8-azaspiro[bicyclo-[3.2.1]octane-3,4′-imidazolidine]-2′,5′-dione

The title compound 1′-Benzyl-8-(4-fluorobenzyl)-8-azaspiro[bicyclo[3.2.1] octane-3,4′-imidazolidine]-2′,5′-dione, C₂₃H₂₃FN₃O₂ is synthesized and the structure is investigated by X-ray diffraction studies. The compound crystallizes in the triclinic crystal class in the P1 space group. The hydantoin ring adopts a planar conformation and is affected by the π conjugation. The pyrrolidine and piperidine rings in the bicyclo octane moiety adopt envelope and chair conformations respectively. The structure exhibits both inter- and intramolecular hydrogen bonds of the type N-H...O, C-H...O, and C-H...N. The oxygen atom in the hydantoin ring simultaneously accepts two hydrogen bonds to form a three-centered hydrogen bonding pattern.     

Formation and Pyrolysis of 1-(2′-Thiazolo [5,4-b] Pyridyl)-5-Aryltetrazoles

1-(2′-Thiazolo [5,4-b] pyridyl)-5-aryltetrazoles (4) have been obtained by the reaction of 2-aroylaminothiazolo [5,4-b] pyridines (2) with phosphorus pentachloride and azidolysis of the resulting imidoyl chlorides. The products of pyrolysis of 1-(2′-thiazoio [5,4-b] pyridyl)-5-aryltetrazoles in decalin have been characterised as 2-aryl-1,2,4-triazolo [3′,2′:2,3]thiazolo[5,4-b] pyridines (6).     

Spectrophotometric and thermal lens determination of aluminum with 3-sulfo-5-nitro-4′-diethylamino-2,2′-dihydroxyazobenzene

The conditions of the spectrophotometric and thermal lens determination of aluminum with sulfo-5-nitro-4′-diethylamino-2,2′-dihydroxyazobenzene have been compared. The limit of spectrophotometric detection of aluminum in aqueous solutions has been found to be 8 ng/mL. On the basis of the conditions of spectrophotometric determination, the conditions for thermal lens determination have been proposed (532.0 nm, exciting radiation power of 42 mW); they provide a decrease of the detection limit down to 0.6 ng/mL and an increase of the sensitivity coefficient by an order of magnitude. It has been shown that, in the case of the thermal lens determination of aluminum in water-organic mixtures (50 vol % of dimethyl sulfoxide or 30 vol % acetonitrile), the sensitivity coefficient is respectively 9.1 and 6.3-fold higher as compared with the thermal lens determination in water. As a result, the detection limits are reduced 2.5 and 10-fold, respectively. Aluminum has been determined by thermal lens spectrophotometry in Moscow’s tap water using the standard addition method, its concentration being 0.79 ± 0.07 mg/L, which is above the threshold limit value of the aluminum content of drinking water.     

2-[2′-(6′-Methyl-benzothiazolyl)azo]-5-dimethylaminobenzoic acid as a new reagent for rapid spectrophotometric determination of copper

2-[2-(6-methyl-benzothiazolyl)azo]-5-dimethylaminobenzoic acid (MBTAMB) has been synthesized and employed as a new reagent for the spectrophotometric determination of copper(II). A blue complex is formed from MBTAMB and Cu(II) in the range of pH 2.0–5.0 in aqueous ethanol. The composition of the complex is Cu(II) MBTAMB=1 1. The maximum absorption of the complex is at 660 nm, its apparent molar absorptivity is 7.0 × 10⁴ 1· mole^–1 · cm^–1. Beer's law is obeyed for copper in the range of 0–0.72 g/ml. The method has been used for the determination of micro amounts of copper in aluminium alloy. The proposed method is simple, rapid and accurate.     

Synthesis and Herbicidal Activity of 2-Benzoyliminopyrimido[3,2-b]-1 2,4-Thiadiazolines

SincethesynthesisandherbicidalactivityofDPX-4l89wasreportedinl98o,awidevarietyofsulfonylureaswithimprovedselectivityand/oreffectivenesshavebeendeveloped'-'.Inacontinuingstudyonthesynthesisandherbicidalactivityofthiophenesulfonylureaandsubstitutedbenzenesulfonylureaderivatives'-',wehavefoundthatsulfonylureaherbicideshaveexcellentherbicidalactivityagainstawiderangeofweeds,butmostofthemwerenotselectivelyactiveherbicides.Inthispaperwedescribethesynthesisandherbicidalactivityofthirteen3-benzoly-l-…     

Vibrational spectra of the dithieno[3,2-b: 2′,3′-d] thiophene crystal

A normal mode analysis of dithieno[3,2-b:2′,3′-d]thiophene crystal was carried out using an intramolecular force field refined for the isolated molecule and an intermolecular potential described in terms of interactions among non-bonded atoms. Infrared and Raman data for internal and lattice vibrations are reported, including those for a deuterated isotopomer, which are satisfactorily accounted for by frequency calculations. Cartesian displacements for each normal mode of the isolated molecule are presented and frequency splittings and shifts analysed through calculations at k = 0 which include all crystal vibrational degrees of freedom.     

New convenient synthesis of substituted 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-b]pyridines and 6,9-dihydropyrido[3′,2′:4,5]thieno[3,2-d]pyrimidines

1,4-Dihydro-3-cyano-2-pyridinethiolates react with 2-bromo-l-(4-bromophenyl)ethylidenemalononitrile or N-cyanochloracetanudine to give 6, 9-dihydropyrido[3, 2': 4, 5]thieno[3. 2-b]pyridines or 6, 9-dihydropyrido-[3.2:4.5Jthieno(3,2-d]pyrimidines, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 553–556, April, 1996.     

Synthesis and reactions of new 4-chloro-2-methylpyrimidino[4′,5′:4,5]thiazolo[3,2-a]-benzimidazoles

Summary 4-Chloro-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazole (3) was prepared by chlorination of2 which could also be converted directly to 2-methylpyrimidino[4,5:4,5]-thiazolo[3,2-a]benzimidazol-4-thiol (4). Nucleophilic substitution of3 with alcohols, phenols, primary amines, secondary amines, sodium azide, and mercaptoacetic acid gave the corresponding derivatives. The thiol derivative4 was reacted with alkyl/aralkyl halides, phenacyl bromide derivatives, bromoacetone, chloroanilides, bromomalonic ester, and ethyl bromoacetate to afford compounds of potential pharmacological interest.

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Synthese und Reaktionen neuer 4-Chlor-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazole

Zusammenfassung 4-Chlor-2-methylpyrimidino[4,5:4,5]thiazolo[3,2-a]benzimidazol (3) wurde durch Chlorierung von2, welches auch direkt zu 2-Methylpyrimidino[4,5:5,4]thiazolo[3,2-a]-benzimidazol-4-thiol (4) umgesetzt werden kann, hergestellt. Nucleophile Substitution von3 mit Alkoholen, Phenolen, primären Aminen, sekundären Aminen, Natriumazid und Mercaptoessigsäure ergab die entsprechenden Derivate. Das Thiolderivat4 wurde mit Alkyl/Alkarylhalogeniden, Phenacylbromidderivaten, Bromaceton, Chloraniliden, Brommalonsäureester und Bromessigsäureethylester zu potentiell pharmakologisch interessanten Verbindungen umgesetzt.

     

The application of copolymer-coated graphene oxide-Fe3O4 in the highly efficient synthesis of 2′-aminospiro[indeno[1,2-b]quinoxaline-11,4′-[4'H] pyran]-3′-carbonitrile and 2′-aminospiro[indeno-2,4′-[4'H]pyran]-3′-carbonitrile

A magnetic nanocomposite based on graphene oxide was prepared. Fe₃O₄ nanoparticles were loaded on graphene oxide sheets and GO-Fe₃O₄ was covered by aniline-pyrrole copolymer to afford poly(Py-co-Ani)@GO-Fe₃O₄. This nanocomposite was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, vibrating sample magnetometry, X-ray diffraction, thermogravimetric analysis, and X-ray photoelectron spectroscopy techniques, and its catalytic activity was evaluated in the multicomponent synthesis of 2′-aminospiro[indeno[1,2-b]quinoxaline-11,4′-[4'H]pyran]-3′-carbonitrile and 2′-aminospiro[indeno-2,4′-[4'H]pyran]-3′-carbonitrile derivatives. This magnetically separable catalyst is heterogeneous noncorrosive, highly efficient, and reusable.