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1.
K. I. Lopatina S. M. Klyuev V. A. Zagorevskii 《Chemistry of Heterocyclic Compounds》1970,6(11):1365-1366
Interconversion of 2-alkyl-4,4-diethyl-4H-1,3-benzoxazines and N-acyl-,-diethyl-o-hydroxybenzylamines was accomplished, and it is shown that cupric ion catalyzes these reactions.See [1] for Communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1465–1466, November, 1970. 相似文献
2.
Summary We have suggested an improved method for preparing , -dinitroalkanes which consists in the action of silver nitrite on , -dibromoalkanes in petrofeum ether medium with heating. 相似文献
3.
H. F. Bauer 《Journal of Thermal Analysis and Calorimetry》1989,35(5):1571-1602
The steady local temperature distribution has been determined for arbitrary prolate spheroidal systems with various boundary conditions. The temperature was derived for all possible systems, such as when the temperature was kept constant on the hyperbolic surfaces and variable on the prolate spheroidal surfaces, and vice versa. In'the latter case, roots with respect to the degree of the associated Legendre function for arguments larger than unity had to be determined. Some of the presented solutions have been evaluated numerically, and the isothermal surfaces have been presented.
Zusammenfassung Für beliebig ausgedehnte sphäroide Systeme wurde mit verschiedenen Randbedingungen eine stationäre lokale Temperaturverteilung ermittelt. Die Temperatur wurde für alle möglichen Fälle ermittelt, so auch für den Fall, in dem die Temperatur an der Hyperbeloberfläche konstant gehalten und an den ausgedehnten sphäroiden Flächen veränderlich ist bzw. umgekehrt. Für letzteren Fall mußten für Argumente größer als eins Wurzeln betreffs des Grades der zugehörigen Legendre Funktion ermittelt werden. Einige der dargestellten Lösungen wurden numerisch ermittelt und die isothermen Flächen dargestellt.
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4.
A. V. Kamernitskii V. A. Krivoruchko I. G. Reshetova E. I. Chernoburova 《Chemistry of Natural Compounds》1981,17(2):142-145
The synthesis of the 17(20)-16 analog of natural chiogralactone is described. Attempts to introduce a 6-oxo group directly into the -lactone proved unsuccessful, since the first stage — saponification — took place with the formation of three products: the 3-hydroxy--lactone, the 3-hydroxy-20(22)-lactone, and the 15,17(20)-dienoic acid. The synthesis of the desired compound was effected from the ethyl ester of the 5,16-dienoic acid by the scheme 3-acetate3-tosylate6-hydroxy-3,5-cyclosteroid6-oxo-3,5-cyclosteroid6-oxo-5H--lactone. It has been shown that the cyclopropane ring in the 3,5-cyclosteroid -lactone is extremely stable under the conditions of acid treatments.N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 184–187, March–April, 1981. 相似文献
5.
A. M. Turuta A. V. Kamernitskii N. V. Dzhlantiashvili L. K. Kavtaradze A. A. Korobov 《Russian Chemical Bulletin》1991,40(5):1063-1066
A new and more effective sequence of reactions is proposed for the production of 16,17-isopropylidenedioxy-5-pregnane-3,21-diol-20-one. It uses methods previously unused for 5-H-steroids and involves 21-hydroxylation of 16,17-epoxy-5-pregnan-3-ol-20-one with diacetoxyiodobenzene and cis-opening of the obtained 21-hydroxy-16,17-epoxy-5-pregnane-3,21-diol-20-one by acetic acid in the presence of epoxycarbonylhydrazine, followed by condensation of the obtained product with acetone.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1185–1188, May, 1991. 相似文献
6.
Masahiko Miyauchi Yoshinori Kawaguchi Akira Harada 《Journal of inclusion phenomena and macrocyclic chemistry》2004,50(1-2):57-62
-Cyclodextrin having cinnamamide at 6- or 3-positions (6-CiNH--CD, 3-CiNH--CD) and -cyclodextrin with cinnamamide on 6-position (6-CiNH--CD) have been prepared. Supramolecular structures were formed in the solid state or aqueous solutions and characterized by measurements of NMR and vapor pressure osmometry (VPO). The results indicate that 6-CiNH--CD formed insoluble supramolecular polymers in the solid state, while 6-CiNH--CD and 3-CiNH--CD formed supramolecular complexes in aqueous solutions. 6-CiNH--CD was found to form a dimer in an aqueous solution. 3-CiNH--CD formed intermolecular complexes to give supramolecular polymers. The differences of the position of guest part on cyclodextrins caused to give a variety of supramolecular structures in aqueous solutions. 相似文献
7.
Conditions have been selected for performing thein vitro biosynthesis of asterosaponins from cholesterol and other sterols in homogenates and cultures of the gonads and pyloric ceca of Far Eastern starfish. It has been shown that the aglycone moiety of an asterosaponin can be biosynthesized from cholesterol, cholesterol sulfate, 5-cholestanol, and 3,6-dihydroxy-5-cholestane but not from 3, 6-dihydroxy-5-cholestane. Of the give precursors studied, cholesterol was transformed into asterosaponins most completely.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 663–667, September–October, 1985. 相似文献
8.
Cyclization of -cyano--phenylamino-N-dimethylaminomethyleneacrylamide to pyrimido[5,4-c]quinol-4-one proceeds via the intermediate formation of 1-phenyl-5-cyano-1,4-dihydropyrimidin-4-one and -cyano--phenyl-amino-N-formylacrylamide.For Communication 50, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 88–90, January, 1988. 相似文献
9.
T. N. Makar'eva I. A. Gorshkova B. A. Gorshkov A. I. Kalinovskii V. A. Stonik 《Chemistry of Natural Compounds》1987,22(4):411-415
Five new sulfated derivatives of sokotrasterol and halistanol have been obtained: 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate); 24-nor-5-cholane-2,3,6,23-tetraol 2,3,6-tri(sodium sulfate) 23-palmitate; 24,25-dimethyl-5-cholestane-2,3,6-triol 3-(sodium sulfate); 24,25-dimethyl-5-cholestane-2,3,6-triol 6-(sodium sulfate); and 24,25-dimethyl-5-cholestane-2,3,6-triol 2,6-di(sodium sulfate). The inhibiting and membranolytic properties of the polysulfated steroids from sponges and their derivatives have been studied. It has been shown that physiological activity in this series of compounds depends on biphilicity.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 441–445, July–August, 1986. 相似文献
10.
L. V. Gorshkova V. P. Zvolinskii N. S. Prostakov A. V. Varlamov M. Torres V. F. Zakharov 《Chemistry of Heterocyclic Compounds》1980,16(12):1245-1248
The diene condensation of 1,3-diphenyl-2-azaanthracene with maleic anhydride proceeds under more severe conditions than the analogous condensation with anthracene. On the basis of an analysis of the PMR data for the adduct obtained it was assumed that isomers of ,-[9,10-dihydro-2-aza-1,3-diphenylanthrylene(9,10)]succinic anhydride with respect to the position of the anhydride bridge relative to the pyridine ring are formed in this condensation. 9,10-Dihydro-2-aza-1,3-diphenyl-9, 10-(1-cyanoethylene)anthracene was obtained in the condensation of the same azaanthracene with acrylonitrile. ,-[5H-8-Aza-7-phenylbenzo[a]fluoranthrylene (5,12b) ]succinic anhydride is formed as a result of the similar condensation of 8-aza-7-phenylbenzo[a]fluoranthene with maleic anhydride, while isomeric (with respect to the position of the nitrile group in the ethylene bridge) 5H-8-aza-7-phenyl-5,12b-(cyanoethylene)benzo[a]fluoranthenes were isolated in its condensation with the acrylonitrile. Data from the PMR and IR spectra were used to prove the structures of the adducts of the diene synthesis obtained.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1645–1647, December, 1980. 相似文献
11.
The production of polymeric microspheres via aerocolloidal processing is explored. A droplet consisting of a mixture of 1,6-hexanediol diacrylate and trimethylolpropane ethoxy triacrylate monomers was levitated electrodynamically in the path of an argon ion laser beam (=488 nm). The laser beam served as the source of illumination for elastic and inelastic light-scattering measurements. The reaction was followed by Raman spectroscopy, and polymerization was initiated with an -amino acetophenone derivative which undergoes -cleavage upon exposure to the laser light. The diameters of the suspended droplets were typically 20–80 m, producing polymeric microspheres of approximately the same size. The size and refractive index of the product microspheres were determined by elastic light-scattering. The Raman data show the elimination of carbon-carbon double bonds and the formation of C–H bonds as rapid polymerization proceeded. 相似文献
12.
Zusammenfassung Durch Umsetzung von ,-Dichloracetophenon mit überschüss. prim. Amin und Schwefel in äther. Lösung unter Zusatz von K2CO3 (Reaktionszeit 140 Stdn., Reaktionstemp. max. 20°) können N,N-disubstituierte -Iminophenylglyoxylsäurethionamide (1–3) in guten Ausbeuten synthetisiert werden.-Iminoglyoxylsäurethionamide (4–6), die am Imin- bzw. Aminstickstoff auch unterschiedlich substituiert sein können (4, 6), erhält man aus den entsprechenden Phenylglyoxylsäurethionamiden durch Umsetzung mit überschüss. primären Aminen.Die -Iminophenylglyoxylsäurethionamide können bereits bei Raumtemp. glatt durch H2S zu den entsprechenden Phenylessigsäurethionamiden reduziert werden.
4. Mitt.:F. Asinger, A. Saus undA. Mayer, Mh. Chem.98, 825 (1967).
Vgl. auchF. Asinger undH. Offermanns, Angew. Chem.79, 953 (1967). 相似文献
Synthesis of N,N-disubstituted -iminophenyl-thioglyoxylic amides, and their reduction by means of H2S to phenyl-thioacetic amides (Willgerodt—Kindler reaction, V.)
N,N-Disubstituted -iminophenylthioglyoxylamides (1–3) can be synthesized in good yields by the reaction of ,-dichloroacetophenone with excess primary amine and sulphur in eth. solution in the presence of potassium carbonate (reaction period 140 hours, reaction temperature max. 20°C).-Iminothioglyoxylamides (4–6), which may be differently substituted at the imine and amine nitrogen atoms (4, 6), may be obtained from the corresponding phenylthioglyoxylamides by reaction with an excess of primary amines.The -iminophenylthioglyoxylamides can be reduced smoothly at room temperature by hydrogen sulphide to the corresponding phenylthioacetamides.
4. Mitt.:F. Asinger, A. Saus undA. Mayer, Mh. Chem.98, 825 (1967).
Vgl. auchF. Asinger undH. Offermanns, Angew. Chem.79, 953 (1967). 相似文献
13.
A. A. Kicha A. I. Kalinovskii N. I. Ivanchina Yu. N. El'kin V. A. Stonik 《Russian Chemical Bulletin》1994,43(10):1726-1730
Four new polyhydroxysteroids, 5-cholesta-3,5,6,15,16,25,26-heptaol, 24-ethyl-5-cholesta-3,5,6,15,28,29-heptaol-29-sulfate, (22E)-24-methyl-5-cholest-22-ene-3,5,6,15,25,26-hexaol-26-sulfate, 24-propyl-5-cholesta-3,5,6,8,15,28,29-heptaol, and the known 5-cholesta-3,5,6,15,16,26-hexaol, have been isolated from the starfishCtenodiscus crispatus.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1821–1825, October, 1994. 相似文献
14.
The capacity of antibodies to various synthetic peptides of -bungarotoxin for binding peptides of the neurotoxin and recognizing the corresponding regions of the -bungarotoxin molecule has been investigated. It has been established that individual conformational sections of the -bungarotoxin molecule are specifically recognized by antibodies to synthetic epitopes of the neurotoxin.Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 502–506, July–August, 1999. 相似文献
15.
V. L. Gein S. G. Pitirimova O. V. Vinokurova Yu. S. Andreichikov A. V. Komkov V. S. Bogdanov V. A. Dorokhov 《Russian Chemical Bulletin》1994,43(8):1398-1401
During thermolysis 6-aryl-2,2-dimethyl-1,3-dioxin-4-ones react with -mono and ,-dioxoketene aminals to yield 3-acetyl-6-aryl-2-benzoylamino-4-pyridones or 6-aryl-2-methylene-4-pyrimidones, respectively. A scheme of the formation of pyrido[2,3-d]pyrimidines from dioxinones and 1-amino-1-benzoylamino-1-bytene-3-one has been suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1475–1478, August, 1994. 相似文献
16.
Steroid compounds from the starfish Lysastrosoma anthosticta collected in the Sea of Japan 总被引:1,自引:0,他引:1
Levina E. V. Andriyashchenko P. V. Kalinovsky A. I. Dmitrenok P. S. Stonik V. A. Prokof"eva N. G. 《Russian Chemical Bulletin》2002,51(3):535-539
Six polyhydroxylated steroids and their derivatives were isolated from the starfish Lysastrosoma anthosticta collected in the Posyet Bay, Sea of Japan. These include a new glycoside of the steroid polyol, lysastroside A (1), which was identified as (25S)-26-O--d-xylopyranosyl-5-cholestane-3,6,8,15,16,26-hexaol, and the previously known pycnopodioside C monoglycoside (2), marthasterone sulfate (3), (25S)-5-cholestane-3,6,8,15,16,26-hexaol (4), (25S)-5-cholestane-3,6,7,8,15,16,26-heptaol (5), and (25S)-5-cholestane-3,6,7,8,15,16,26-heptaol (6). The compounds were tested for the haemolytic activity and the action on the embryogenesis of the sea urchin Strongylocentrotus intermedius. 相似文献
17.
Condensation of 2,4,5-tribenzyloxybenzaldehyde with -cyanoacetic acid gave 2,4,5-tribenzyloxyphenyl--cyanoacrylic acid which on decarboxylation gave 2,4,5-tribenzyloxyphenylacrylonitrile. Stepwise reduction of the double bond with sodium amalgam and then the cyano group with diborane followed by catalytic hydrogenolysis afforded 2,4,5-trihydroxyphenylpropylamine.
Synthese von 2,4,5-Trihydroxyphenylpropylamin (Kurze Mitteilung)
Zusammenfassung Die Kondensation von 2,4,5-Tribenzyloxybenzaldehyd mit -Cyanessigsäure ergab 2,4,5-Tribenzyloxyphenyl--cyanacrylsäure; diese ergab nach Decarboxylierung 2,4,5-Tribenzyloxyphenylacrylnitril. Stufenweise Reduktion der Doppelbindung mit Natriumamalgam und dann der Cyano-Gruppe mit Diboran gefolgt von katalytischer Hydrogenolyse führte zu 2,4,5-Trihydroxyphenylpropylamin.相似文献
18.
K. K. Koskoev A. P. Shchelochkova I. G. Reshetova A. V. Kamernitskii V. S. Bogdanov 《Chemistry of Natural Compounds》1984,19(4):440-444
The pathways of the chemical transformation of aglycones and their glycosides that do not affect the glycosidic chain are considered. Starting from 3-hydroxy-5-pregn-16-en-20-one 3-0-[0--D-glucopyranosyl-(1 2)-0--D-glucopyranosyl-(1 4)--D-galactopyranoside] the corresponding 16(H),17(OH)-dihydropyranone glycoside has been obtained. The latter has been converted into the polyacetate of a glycoside with a 17,20-dihydroxytetrahydropyran ring E. The structure and stereochemistry of the final compound have been shown from the results of the1H and13C NMR spectra and mass spectra.Institute of Organic Chemistry, Academy of Sciences of the Kirghiz SSR. N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 469–472, July–August, 1983. 相似文献
19.
Summary Two triterpene glycosides — caulosides b and c — have been isolated from a methanolic extract of the leaves ofCaulophyllum robustum maxim. Cauloside b has been identified as hederagenin 3--L-rhamnopyranosyl-(12)--L-arabinopyranoside, while cauloside c has the structure of hederagenin 3-0--L-arabinopyranosyl(13)--L-pyranosyl-(12)--L-arabinopyranoside.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 174–176, March–April, 1979. 相似文献
20.
Stoikov I. I. Fitseva N. A. Akhmetzyanova L. R. Gafioullina L. I. Antipin I. S. Zheltukhin V. F. Devyaterikova A. I. Al"fonsov V. A. Konovalov A. I. 《Russian Chemical Bulletin》2004,53(7):1577-1583
New -amino phosphonates containing different alkyl and aryl substituents at the -carbon atom were synthesized in high yields by the Kabachnik—Fields and Pudovik reactions. These compounds were studied as carriers of several -hydroxy carboxylic and dicarboxylic acids through liquid impregnated membranes. These -amino phosphonates studied are capable of molecular recognition of oxalic acid among structurally similar -hydroxy carboxylic and dicarboxylic acids. The efficiency and selectivity of mass transfer of oxalic acid increase with an increase in the lipophilicity of the -amino phosphonate. 相似文献