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1.
The coupling of benzimidazolo[2, 1:2, 3]thiazolidin-4-one with benzenediazonium chlorides in acetic acid in the presence of sodium acetate at pH 4.5–4.0 has yielded 5-arylazo derivatives of the thiazolidone. By a study of the IR and UV spectra of the aryl derivatives of benzimidazolo[2, 1:2, 3]thiazolidin-4-one synthesized, it has been shown that the latter has the azo structure.  相似文献   

2.
From 2-amino-1-keto-1, 2, 3, 4-tetrahydronaphthalene, prepared by reduction of isonitroso--tetralone, a number of N-acyl derivatives are prepared, and these are converted further to 2-substituted 3, 4-dihydronaphth-1, 25, 4-oxazoles,  相似文献   

3.
On electrolysis mono- and bicyclic furfuryl-substituted alcohols undergo intramolecular alkoxylation, giving polycyclic spirans. Spiro[perhydrobenzofuran-2, 2-(5-methoxy, 5H)furan] and spiro[4H, 5H, 6H, 11H-naphtho-(,)-furan-2(3H)] [2-(5-methoxy, 5H)furan], hitherto not described, are prepared in this way. On catalytic hydrogenation they give the previously unknown spiro[perhydrobenzofuran-2, 2-tetrahydrofuran] and spiro[4H, 5H, 6H, 11H-naphtho-(,)-furan-2(3H)][2-tetrahydrofuran].For Part XXIX see [1].  相似文献   

4.
Summary -Chloro--cyano-cinnamonitrile (1) reacts in one step with -oxo-thioles3 or successively with sodium sulphide and -chlorocarbonyl compounds4 to form the 5-substituted 4-amino-2-phenyl-thiophene-3-carbonitriles5. Analogously, the successive reactions of -chloro cinnamonitrile1 with sodium selenide — produced in situ from selene and sodium boronhydride — and -chlorocarbonyl compounds4 yields the 5-substituted 4-amino-2-phenyl-selenophene-3-carbonitriles6.
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5.
Zinc oxide heterogeneously catalyzes formaldehyde condensation to a complex mixture of formose sugars. The reaction proceeds at pH 5.5 and unwanted Cannizzaro side reaction does not occur. The catalyzed reaction is exceptionally slow. At 100°C and 1.00 M ZnO, 0.61 M HCHO starting concentration, the induction period lasts 70 h and 90% conversion does not occur until 92 h. Either addition of D-glucose co-catalyst or reduction in the starting ratio of HCHO to ZnO eliminates the induction period.
. pH=5,5 . . 100°C ZnO 1,00 M HCHO 0,61 M 70 , 90%- 92 . -D-, HCHO ZnO
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6.
The effect of calcination temperature on the catalytic properties of nickel phosphate has been studied using the isomerization of butene-1 as a test reaction. A simple relationship was found between the catalyst activity in isomerization and the hydroxy content of the catalyst surface. Interrelations between the activity of the catalyst and its structure are discussed.
, -1 . . .
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7.
According to results obtained previously for the linear equations of chemical kinetics, the relation between the steady-state reaction rate and the relaxation time has been studied.
, , .
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8.
Accurate data are presented on the behaviour of the thermal conductivity K as a function of temperature for a pure Ni sample near its Curie point. Previous results on the electrical resistivity (, d/dT are used to explain the temperature-dependence ofK(T). The results are analysed in terms of electron-phonon ands- d exchange interactions. The critical behaviour of the thermal resistivityW(=K–1) has also been investigated.
Zusammenfassung Die WärmeleitfähigkeitK einer reinen Nickelprobe wurde in der Nähe des Curiepunktes in Abhängigkeit von der Temperatur beschrieben. Vorangestellte Untersuchungen des elektrischen Widerstandes (, d/dT wurden benutzt, um die Temperaturabhängigkeit von K zu erklären. Die Ergebnisse wurden unter Inbetrachtnahme von Elektron-Photon unds-d-Austausch Wechselwirkungen interpretiert. Das kritische Verhalten des WärmewiderstandesW (=K–1) wurde ebenfalls untersucht.

K . K() - (, d/dT). - s-d . W(=K–1).
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9.
Two new glycosides have been isolated from the total triterpene glycosides of the holothurianDuasmodactyla kurilensis: kurilosides A (III) and C (IV). It has been established that (III) is 16-acetoxy-3-{[O--D-glucopyranosyl-(1 4)-O--D-quinovopyranosyl-(1 2)]-[O-(3-O-methyl--D-glucopyranosyl)-(1 3)-O-(6-O-(sodium sulfato)--D-glucopyranosyl)-(1 4)]--D-xylopyranosyloxy}-4,4,14-trimethylpregen-9(11)-en-20-one, while the minor glycoside (IV) is 16-acetoxy-3-{O--D-quinovopyranosyl-(1 2)-[O-(3-O-methyl--D-glucopyranosyl-(1 3)-O-(6-O-(sodium sulfato)--D-glucopyranosyl)-(1 4)]--D-xylopyranosyloxy}-4,4,14-trimethylpregn-9(11)-en-20-one.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–226, March–April, 1991.  相似文献   

10.
New coumarin glycosides — haploperosides C, D, and E — have been isolated from the epigeal part of theHaplophyllum performatum (MB) Kar et Kir. On the basis of chemical transformations and spectral characteristics, haploperoside D has the structure of 6-methoxy-7-[0--L-rhamnopyranosyl-(1 2)--D-glucopyranosyloxy]-2H-benzopyran-2-one, and haploperoside C that of 6-methoxy-7-[0--L-rhamnopyranosyl-(1 6)-(2-0-acetyl--D-glucopyranosyloxy)]-2H-benzopyran-2-one. The structure of haploperoside E has been established as 7-[0--L-rhamnopyranosyl-(1 2)-0--L-rhamnopyranosyl-(1 6)--D-glucopyranosyloxy]-2H-benzopyran-2-one. The structures of haploperosides A and B have been refined. An assignment has been made of the carbon signals in the13C NMR spectra of haploperosides A, D, C, and E.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 27–35, January–February, 1985.  相似文献   

11.
The strength of protonic sites and the concentration of acid centers in V2O5/Al2O3 catalysts have been estimated according to pyridine and ammonium adsorption.
V2O5/Al2O3.
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12.
Research on synthesis of polycyclic spirans of the 1, 6-dioxaspiro-[4, 4]nonane group is continued. Electrolysis of methanol solutions of 2-furylcyclopentanol, 2-(5-methyl-furfuryl)cyclopentanol, and 2-furfuryl-1-indanol, gives, by intramolecular alkoxylation, spiro{perhydrocyclopenta[b]furan-2, 2-(5dihydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-(5-methoxy-5-methyl-2, 5-dihydrofuran)}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxy-2, 5-dihydrofuran)}, hitherto undescribed in the literature. Depending on the conditions, catalytic hydrogenation of these gives: spiro{perhydiocyclopenta[b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{2, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-(5-methoxytetrahydrofuran)}, spiro{perhydrocyclopenta[b]furan-2, 2-tetrahydrofuran}, and spiro{2, 3, 3a, 8b-tetrahydro-4H-indeno[1, 2-b]furan-2, 2-tetrahydrofuran}.For Part XXXI see [1].  相似文献   

13.
The acidity and catalytic activity of alumina doped with AlCl3, CH3AlCl2, PCl5, PCl3, I2, Cl2 and H2PO3F were studied. Vapors of AlCl3 and CH3AlCl2 induce superacid sites in alumina, whereas PCl3 and PCl5 produce less acidic systems, which nevertheless catalyze the skeletal isomerization of alkenes. The modification of Al2O3 with other specified compounds affects only slightly the acidity and catalytic activity of alumina.
AlCl3, CH3AlCl2, PCl5, PCl3, I2, Cl2 H3PO3F. AlCl3 CH3AlCl2 - . PCl3 PCl5 - , . Al2O3 - .
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14.
4-Amino-1,2,4-triazol-5-one hydrate (ATO·H2O) was prepared and its structure was analyzed by four-circle diffraction measurement. The obtained results show that the crystal belongs to the triclinic crystal system, space group P 1 with crystal parameters a = 6.432(1), b = 6.551(1), c = 6.740(1) ; = 68.04(1), = 82.18(1), = 81.90(1)°, V = 259.7(7) 3; Z = 2; Dc = 1.510 g/cm3; = 0.131 mm-1; F(000) = 124. ATO·H2O was characterized by FT-IR analysis, X-ray diffraction analysis, and single crystal diffraction analysis.  相似文献   

15.
Alkylation of 3-thiocarbamoyl-3,4,5,6-tetrahydropyridine-2(1H)-one with methyl iodide has given 5-methylthio-2,6-diazabicyclo[2.2.2]oct-5-en-3-one and 3-methyl-thiocarbonyl-3,4-dihydropyridine-2(1H)-one. Alkylation of 3-thiocarbamoyl-3,4-dihydridine-2(1H)-one with iodoacetamide affords 3-(1-amino-1-carbamoyl-3,4-methyl-thiomethylene)-1,4-dihydropyridine-2-one, which in acidic media is converted into 3-(4-oxo-3,5-dihydro-1,3-thiazol-2-ylidene)-1,4-dihydropyridine-2-one.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 787–794, June, 1989.  相似文献   

16.
The influence of different degrees of distortion of the coordination polyhedra in some Cu(II) complexes on the courses of their thermal destruction was studied. It was found that differences in the thermal stability and stoichiometry of thermal decomposition may be satisfactorily explained by the different degrees of distortion of the coordination polyhedra in the Cu(II) complexes under discussion. This fact appears to be significant with respect to the chemical reactivities of these complexes, though the influence of other factors cannot be excluded.
Zusammenfassung Der Einfluß der verschiedenen Grade der Koordinations-Polyeder-Verzerrung in einigen Cu(II) Komplexen auf den Verlauf ihrer thermischen Zersetzung wurde untersucht. Es wurde festgestellt, daß Unterschiede in der thermischen Stabilität und der Stöchiometrie der thermischen Zersetzung durch die verschiedenen Verzerrungsgrade der Koordinations-Polyeder in den erörterten Cu(II) Komplexen befriedigend erklärt werden können. Diese Tatsache scheint hinsichtlich der chemischen Reaktivität dieser Komplexe von grosser Bedeutung zu sein, obwohl der Einfluß anderer Faktoren nicht ausgeschlossen werden kann.

Résumé On a étudié l'influence des différents degrés de distortion des polyhèdres de coordination sur l'allure de leur décomposition thermique, dans le cas de quelques complexes du Cu(II). On a trouvé que les différences de stabilité thermique et de stoechiométrie pouvaient expliquer de manière satisfaisante les différents degrés de distortion des polyhèdres de coordination dans les complexes du Cu(II) étudiés. Ce fait semble être plutôt significatif de la réactivité chimique de ces complexes, bien que l'influence d'autres facteurs ne doive pas être exclue.

Cu(II) . , -, Cu(II). , -, , .


Presented at the 7th Czechoslovak National Conference on Thermal Analysis (TERMANAL); The High Tatras, 1976.  相似文献   

17.
2-Amino, 2-amino-3-methyl-, and 4-aminopyridine react with -chloro--isonitrosoacetone at the heteroring nitrogen atom to give salts, which are converted to imidazo[1,2-a] pyridines or, in the case of 4-aminopyridine, to 1-(1-oximino-2-oxopropyl)-4-pyridoneimine when they are treated with alkali. Acetylpyridylurea was obtained from chloroisonitrosoacetone and 2-aminopyridine in pyridine.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1525–1529, November, 1978.  相似文献   

18.
The influence of oscillations in the feed concentration on the selectivity of a catalytic process has been studied for parallel reactions. The selectivity increase in periodic operations depends on both the type of kinetic functions and the non-steady-state properties of the catalysts.
. , .
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19.
Obtusinin (1) has been synthesised by the reaction of 6-methoxy-7-(3-methylbut-2-enyloxy)-2H-1-benzopyran-2-one (3) with OsO4. Synthesis of 7-(3-hydroxymethylbut-2-enyloxy)-6-methoxy-2H-1-benzopyran-2-one (2) has been achieved by the regiospecific oxidation of3 with SeO2 followed by reduction of the formed aldehyde with KBH4.
Synthese von Obtusinin und 7-(3-Hydroxymethylbut-2-enyloxy)-6-methoxy-2H-1-benzopyran-2-on
Zusammenfassung Obtusinin (1) wurde über 6-Methoxy-7-(3-methylbut-2-enyloxy)-2H-1-benzopyran-2-on (3) mit OsO4 synthetisiert. Die Darstellung von 7-(3-Hydroxymethylbut-2-enyloxy)-6-methoxy-2H-1-benzopyran-2-on (2) wurde mittels regioselektiver Oxidation von3 mit SeO2, gefolgt von Reduktion des gebildeten Aldehyds mit KBH4, bewerkstelligt.
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20.
New triterpene glycosides have been isolated from the berries of Crimean ivyHedera taurica Carr. (family Araliaceae) — hederoside A1 (methyl ester of 3-O--D-glucopyranosylhederagenin) and hederoside D1 3-O-[O--D-glucopyranosyl]-(12)--D-glucopyranosyl]hederagenin and also the known glycosides 3-O--D-glucopyranosyloleanolic acid and 3-O-[O--D-glucopyranosyl-(12)--L-arabinopyranosyl]hederagenin. The structures of these compounds were established on the basis of the results of chemical methods and1H and13C NMR spectroscopy.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 228–230, March–April, 1990.  相似文献   

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