Derivatives of 3-aminopiperidine-2, 6-dione

Several N-substituted 3-phthalimidopiperidine-2,6-diones and 3-(3phthalimido-2,5-dioxopyrrolid-1-yl)piperidine-2,6-dione have been synthesized.     

Heterylimidazoles IV. Homolytic dissociation of hexaaryldimidazolyls and their heterocyclic analogs

The rate constants and activation energies for homolytic dissociation of 2,2-di[ ()-naphthyl]-, 2,2-diquinolinyl-, and 2,2-di(9-acridinyl)-4,4,5,5-tetraphenyldiimidazolyls in toluene in the presence of,-diphenyl--picrylhydrazine were determined. The degrees of dissociation of the diimidazolyls were found. The effect of substituents on the stability of imidazolyl radicals is discussed.See [1] for communication III.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1536–1539, November, 1974.     

Reaction of dibepin with amino acids on chromatographic paper

A method was developed for the development of amino acids and some of their derivatives on Chromatographic paper by means of dibepin-8-[2,3(CO),6,5(CO)-dibenzoylene-4-pyridyl]-l-naphthoyl chloride. The sensitivity was 2 g in the case of glycine ethyl ester hydrochloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 357–358, March, 1972.     

Soluble polysaccharides of Rhodotorula flava

Conclusions 1. Xanthalin has been shown to have the structure of 2, 2-dimethyl-3, 4,-diangeloyloxy-3, 4-dihydropyrano-5, 6:6, 7-coumarin on the basis of the preparation of a number of derivatives and cleavage products.2. The following products of the alkaline hydrolysis of xanthalin have been isolated and characterized for the first time: (±)-3, 4-dihydroxy-3, 4-dihydroxanthyletin (isokhellactone), C₁₄H₁₄O₅, with mp 213–215° C and (–)-trans-3-hydroxy-4-methoxy-3, 4-dihydroxanthyletin (isomethylkhellactone, C₁₅H₁₆O₅, with mp 136.5–138° C and [] _D ²⁰ –47.7 (ethanol).Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 14–19, 1970     

Direct spectrometric determination of proteins in body fluids using a near-infrared cyanine dye

A new near-infrared (NIR) dye, 1,1-disulfobutyl-3,3,3,3-tetramethylindotricarbocyanine (DTCY) has been developed for the quantitation of proteins in solution. The method is based on the binding of DTCY to proteins under acidic conditions. The binding of DTCY to proteins causes a new band at 814 nm. The maximum binding number of bovine serum albumin (BSA) with DTCY was measured as 100. The linear range is 0.3–40 g mL^–1 for BSA and human serum albumin (HSA), respectively. Except for Fe²⁺, Cu²⁺, and cetyltrimethylammonium bromide, all of the examined coexisting substances show no interference in the assay. The method has been applied to the quantitation of proteins in serum and urine with recoveries between 96 and 105%.     

Nitration,amination, and halogenation of Di-O-methylphloracetophenone

Chlorination of the title compound gave 5- and 3-chloro-2-hydroxy-4,6-dimethoxyacetophenone. The nitration of its acetate, followed successively by reduction, diazotization, and reaction with cuprous chloride, gave the 3-substituted series, 2-acetoxy-4,6-dimethoxy-3-nitroacetophenone, 3-amino-2-hydroxy-4,6-dimethoxyacetophenone, and 3-chloro-2-hydroxy-4,6-methoxyacetophenone, respectively. The orientation of substituents in the products was proved. The amino and chloro members of the isomeric 5-substituted series were availablevia 2-hydroxy-4,6-dimethoxy-5-phenylazoacetophenone, the product of the reaction of the title compound with benzenediazonium chloride.

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Nitrierung, Aminierung und Halogenierung von Di-O-methylphloracetophenon

Zusammenfassung Chlorierung der Titelverbindung gab 5- und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Nitrierung des Acetats, gefolgt von Reduktion, Diazotierung und Reaktion mit CuCl ergab die 3-substituierte Reihe: 2-Acetoxy-4,6-dimethoxy-3-nitroacetophenon, 3-Amino-2-hydroxy-4,6-dimethoxyacetophenon und 3-Chlor-2-hydroxy-4,6-dimethoxyacetophenon. Die Orientierung der Substituenten wird diskutiert. Die Amino- und Chlorderivate der isomeren 5-substituierten Reihe sind über 2-Hydroxy-4,6-dimethoxy-5-phenylacetophenon zugängig, dem Produkt der Reaktion der Titelverbindung mit Phenyldiazoniumchlorid.

     

Fluorescence enhancement method for measuring anionic surfactants with a hydrophobic cyanine dye

A novel fluorimetric method based on use of a hydrophobic cationic cyanine dye has been developed for determination of the anionic surfactant sodium dodecylbenzenesulfonate (DBS). The method is based on the enhancement effect of DBS on the fluorescence of the hydrophobic cyanine dye 2-[-4-chloro-7-(1-ethyl-3,3-dimethylindolin-2-ylidene)-3,5-(propane-1,3-diyl)-1,3,5-heptatrien-1-yl]-1-ethyl-3,3-dimethyl-3H-indolium iodide. Under the optimum conditions the extent of fluorescence enhancement is proportional to the concentration of DBS in the range 0.05–5.0 mg L^–1; the detection limit is 0.014mg L^–1. The relative standard deviation for 0.35 mg L^–1 DBS was 1.1% (n=10). The proposed method, which avoided use of toxic solvents and tedious solvent-extraction, and was applied to the determination of DBS in natural water with recoveries between 99.9 and 107%. Preliminary research shows that the fluorescence enhancement is due to the formation of a dye aggregate facilitated by DBS.     

Bisindoles. 10. Synthesis of 1,2-(5,5′-diindolyl)ethane

A 2,2-diethoxycarbonyl derivative of a new bisindole system, viz., 1,2-(5,5-diindolyl)ethane, was obtained by cyclization of ethyl pyruvate sym-4,4-diphenyleneethanedihydrazone. 5-(-Phenylethyl)-2-ethoxycarbonylindole was also isolated in very low yield from the reaction products. Saponification of the 2,2-diethoxycarbonyl derivative gave the corresponding dicarboxylic acid, the thermal decarboxylation of which leads to the formation of 1,2-(5,5-diindolyl) ethane. The syn,syn and anti,anti forms of ethyl pyruvate sym-4,4-diphenyleneethane-dihydrazone were also obtained and characterized.See [1, 2] for Communications 8 and 9.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 348–351, March, 1982.     

The structure of xanthalin

Conclusions From the roots ofXanthogalum purpurascens growing in the Transcaucasus, we have isolated a new coumarin, C₂₄H₂₆O₇ with mp 111–113°C, [] _D ²⁰ –164.2° (c 0.97; ethanol) which we have called xanthalin. On the basis of the NMR spectrum it has been established that xanthalin is 3, 4-diangeloyl-2, 2-dimethyl-3, 4-dihydropyrano-5, 6:6, 7-coumarin.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 5, pp. 280–283, 1968     

Calorimetric study of the BrO3?/Ce4+/cyclohexanone and BrO3?/Ce4+/cyclopentanone oscillating systems

The heat output (Q) during the induction period of a Belousov-Zhabotinskii oscillating reaction usually evolves at a constant rate /6/; we observe in the BrO ₃ ^– /Ce⁴⁺/Cyclohexanone system a sudden change in the slope of the function Q=f(t), which corresponds to the beginning of the quasistationary phase /3/.

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(Q) - ; BrO ₃ ^– /Ce⁺⁴/ Q=f(t), .

     

Spectrophotometric determination of vanadium with 4-(1′H-1′,2′,4′-Triazolyl-3′-azo)-2-methylresorcinol

Summary 4-(1H-1,2,4-Triazolyl-3-azo)-2-methylresorcinol reacts with vanadium(V) at pH 8.10 (Tris-HClO₄ buffer solution) to produce a pink-violet 11 complex ( _max=525 nm,=2.55×10⁴l·mol^–1· cm^–1) in a 50% (v/v) methanol-water medium, which allows the spectrophotometric determination of 0.1 to 1.51 ppm of vanadium. The method has been applied for the determination of the vanadium content in low alloy steels.

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Spectrophotometriscbe Bestimmung von Vanadin mit 4-(1H-1,2,4-triazo-lyl-3-azo)-2-methylresorcin

Zusammenfassung Vanadin bildet bei pH 8,10 (Tris-HClO₄-buffer) mit 4-(1H-1,2,4-tri-azolyl-3-azo)-2-methylresorcin ein rosenrot-violettes Chelat, dessen Absorptionsmaximum bei 525 nm in Gegenwart von 50% Methylalkohol gemessen wird. Dieser 11-Komplex entspricht bei einer Vanadin-Konzentration von 0,1–1,51g/ml dem Beerschen Gesetz; seine molare Absorptivität ist 2,55×10⁴l·mol^–1·cm^–1. Das Verfahren wurde zur Bestimmung des Vanadins in Stahl verwendet.

     

1,2-bis(2',6'-dimethyl-i',3'-dioxa-6'-aza-2'-silacyclooctyl-2')ethane and the corresponding ethylene and acetylene derivatives

Conclusions The reaction of 1,2-bis(methyldimethoxysilyl)ethane and the corresponding ethylene and acetylene derivatives with bis(2-hydroxyethyl)methylamine gives 1,2-bis(2,6-dimethyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)ethane and the corresponding ethylene and acetylene derivatives. Analogously, 1,2-bis(vinyldimethoxysilyl)acetylene gave 1,2-bis(2-vinyl-6-methyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)acetylene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1420–1421, June, 1988.     

9-(2′,5′-Dimethyl-4′-pyridyl)fluorene in syntheses of fluorospirodihydrofuropyridine and pyridofluoranthene

1,2,5-Trimethyl-4-(9-fluorenylidene)piperidine, which is formed by condensation of fluorene with 1,2,5-trimethyl-4-piperidone, is converted catalytically to 9(2,5-dimethyl-4-pyridyl)fluorene, from which 2-methylpyrido[4,5-a]fluoranthene and its demethylated analog were obtained by catalytic dehydrocyclization. Oxidation of 9-(2,5-dimethy1-4-pyridyl)fluorene gave 9-(2,5-dimethyl-4-pyridyl)9-fluorenol and fluorene-9-spiro-4-(6-oxo-2-carboxypyrido[4,5-c]-4-6-dihydrofuran). 6-Methyl-2-phenyl-7-(9-fluorenyl)indolizine was synthesized by the Chichibabin method.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1087–1090, August, 1978.     

Reactions of pennogenin and related compounds. IV. Formation of (25R,22′R,25′R)-3β,3′β-diacetoxy-26,22′-epoxy-16,16′-bifurosta-5,20(22),5′,17′(20′)-tetraen-26′-ol from pennogenin diacetate under the action of BF3·Et2O

A new direction of the reaction of pennogenin diacetate with BF₃·Et₂O has been discovered in which a previously unknown dimeric steroid is formed — (25R,22R,25R)-3,3-diacetoxy-26,22-epoxy-16,16-bifurosta-5,20(22), 5,17(20)-tetraen-26-ol, the structure of which has been established as the result of an analysis of IR, UV,¹H and¹³C NMR, and mass spectra. A probable mechanism for the formation of the title compound from pennogenin diacetate is suggested.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Institute of Chemistry of Plant Substances, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 202–208, March–April, 1990.     

Investigations in the region of 2,3′-biquinolyl 4. Alkylation of the dianion of 2,3′-biquinolyl

With alkyl chlorides and alkyl phenyl ethers the dianion of 2,3-biquinolyl forms the products from alkylation at position 4. Their treatment with alkyl halides or water gives 1, 4-dialkyl-1, 4-dihydro-2,3-biquinolyls or 4-alkyl-1,4-dihydro-2,3-biquinolyls respectively.For communication 3, see [1].Stavropol State University, Stavropol, Russia 355009. Russian Chemical Technology University, Moscow 125190. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1214–1217, September, 1998.     

Reactivity of benzoic acid esters towards cumylperoxy radicals

The alkoxy groups of aromatic carboxylic acid esters are attacked by cumylperoxy radicals. The rate constants for the abstraction of a hydrogen atom by cumylperoxy radicals are: for methyl benzoate k₂=(4.28±0.8)×10¹⁰ exp (–20.5±1.5/RT) and for ethyl benzoate k₂=(9.41±0.8)×10¹⁰ exp(–18.5±1.5/RT) l/mol sec. The strengths of the primary and the secondary C–H bonds of these compounds have been estimated.

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, . k₂=(4,28±0,8)·10¹⁰ exp (–20,5±1,5/RT) k₂=(9,41±0,8)·10¹⁰ exp (–18,5±1,5/RT) /·. C–H .

     

Effect of hydrolysis catalyst and thermal treatment on titania synthesis via sol-gel

The effect of acidic and basic catalysts and of thermal treatment on the preparation of TiO₂ by the sol-gel method has been studied. The resultant solids were characterized by UV-Vis spectroscopy. A displacement of the band due to a fundamental transition to lower energies was observed when acid catalysts were used.

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, TiO₂ - . . .

     

On the pattern of hydrogenolysis of hexane isomers over four Group VIIIB metals

The hydrogenolysis patterns of five hexane isomers have been compared over Rh, Pd, Ir and Pt. The selectivity of rupture of various C–C bond types is different for various metals. The fingerprint-like patterns are, as a rule, similar to those reported in the literature, their correlation with the position of the metal in the periodic system is pointed out.

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5- Rh, Pd, Ir Pt. C–C , . .