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1.
The total sterols have been isolated fromHalocynthia aurantium by column chromatography on silica gel. The following steroid alcohols have been identified in it with the aid of GLC, GLC-MS, and1H NMR: 5-cholestan-3-ol, 24-methylcholestan-3-ol, 24-ethylcholestan-3-ol, 4-methyl-24-ethyl-5-cholestan-3-ol, cholest-5-en-3-ol, 24-methylcholest-5-en-3-ol, 24-ethylcholes-5-en-3-ol, 5-cholest-22-en-3-ol, 24-nor-5-cholest-22-en-3-ol, cholesta-5,22-dien-3-ol, 24-methylcholesta-5,22-dien-3-ol, 24-norcholesta-5,22-dien-3-ol, 24-ethylcholesta-5,24(28)-dien-3-ol, and 24-methylcholesta-5,24(28)-dien-3-ol.Pacific Ocean Institute of Bioorganic Chemistry of the Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok, and Far-Eastern State University, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 581–585, September–October, 1981.  相似文献   

2.
The effect of two commercially available metal oxide curing agents, PbO2 and MnO2, on the cure time, kinetic parameters and ultimate tensile strength of the polysulphide polymer was investigated. The kinetic parameters for the thermal decomposition of the two systems were evaluated from their TG data. Both the energy of activation and pre-exponential factor showed a systematic increase with increase in cure and levelled off after the reaction. The cure time was also followed by determining the mechanical properties of the samples at regular intervals. The ultimate tensile strength values and the kinetic parameters follow similar trend with respect to the cure time. The kinetic parameters and the ultimate tensile strength for the PbO2 cured polysulphide system were on the higher side.
Zusammenfassung Es wurde der Einfluß von zwei im Handel erhältlichen Metalloxidhärtemitteln. PbO2 und MnO2, auf die Aushärtungszeit, die kinetischen Parameter und die Zugfestigkeit von Polysulfidpolymeren untersucht. Die kinetischen Parameter für die thermische Zersetzung der zwei Systeme wurden aus deren TG-Daten ermittelt. Sowohl die Aktivierungsenergie als auch der präexponentielle Faktor wachsen mit fortschreitender Aushärtung ständig an und erreichen nach Verlauf der Reaktion einen konstanten Wert. In gleichmäßigen Zeitabschnitten wurde die Aushärtungszeit auch durch Bestimmen der mechanischen Eigenschaften der Proben verfolgt. In Bezug auf die Aushärtungszeit zeigen die Zugfestigkeit und die kinetischen Parameter einen ähnlichen Verlauf. Die kinetischen Parameter und die Zugfestigkeit von mit PbO2 gehärteten Polysulfidsystemen zeigen bessere Werte.

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We thank Dr. R. Ramaswamy for supplying the resin and Dr. K. V. C. Rao and Director, VSSC for the kind permission to publish this work.  相似文献   

3.
Two new compounds were isolated from two Far-Eastern starfish species, Henricia sanguinolenta and H. leviuscula leviuscula, collected in the Sea of Okhotsk, viz., the glycoside sanguinoside C, (20R,22E,24R,25S)-3-O-(2,3,4-tri-O-methyl--xylopyranosyl)-24-methyl-5-cholest-22-ene-3,4,6,8,15,26-hexol, and a steroidal ketone, (20R,24S)-3,6,24-trihydroxy-5-cholestan-15-one. They exhibit moderate cytostatic activity with respect to the eggs of sea urchin Strongylocentrotus intermedius.  相似文献   

4.
Two tigogenin glycosides and two diosgenin glycosides have been isolated from a methanolic extract of the roots of bush red pepper. An attempt to isolate the individual spirostanol glycosides directly was unsuccessful. These compounds have very similar structures. For their separation, acetylation and epoxidation of the double bond of the aglycon, diosgenin, in the corresponding glycosides was performed. The derivatives obtained were purified by chromatography. To establish the complete chemical structure of each capsicoside we used both chemical and physical methods; complete and partial acid hydrolysis, methylation followed by methanolysis, IR spectroscopy, mass spectroscopy, etc. It was shown that capsicoside A2 is (25R)-5-spirostan-3-ol 3-O--D-galactopyranoside, capsicoside B2 is (25R)-5-spirostan-3-ol 3-O-[O--D-glucopyranosyl(14)--D-galactopyranoside], capsicoside A3 is (25R)-spirost-5-en-3-ol 3-O--D-galactopyranoside, and capsicoside B3 is identical with funkioside C.Institute of Chemistry, Academy of Sciences of the Moldavian SSR, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 242–246, March–April, 1987.  相似文献   

5.
The binding of a series of alkane-,-diols, HO(CH2)nOH, n = 4 to 7, to - and -cyclodextrin (CD) has been studied by measurements of partial molar volumes (PMVs) and isentropic partial molar compressibilities (PMCs) at 25°C. From the PMV and PMC data, changes in the partial molar quantities upon going from a free state in aqueous solution to a complexed state were evaluated for the diols. Negative changes in PMV and PMC were observed for complex formation with -CD, while positive values were obtained for the -CD complexes. Equilibrium constants for the different complexes, assuming the formation of 1:1 complexes, were evaluated from the PMV and/or PMC data, and were found to increase with increasing chain length of the included diol for both - and -CD complexes. The equilibrium constant for complex formation is generally higher for the -CD than for the -CD complexes.  相似文献   

6.
Summary It has been shown that the roots ofBryonia alba contain cholest-7-en-3-ol, 24-methylcholest-7-en-3-ol, 24-ethylcholest-7-en-3-ol, 24-methylenecholest-7-en-3-ol, 24-ethylidenecholest-7-en-3-ol, 24-ethyl-4-methylcholest-7-en-3-ol, 24-ethylidene-4-methylcholest-7-en-3-ol, and also previously undescribed 3-O--glucopyranosides of the above-mentioned sterols.A. L. Mndzhoyan Institute of Fine Organic Chemistry, Academy of Sciences of the Armenian SSR, Erevan. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 353–360, May–June, 1977.  相似文献   

7.
Gromova  A. S.  Lutsky  V. I.  Cannon  J. G.  Li  D.  Owen  N. L. 《Russian Chemical Bulletin》2001,50(6):1107-1112
The chemical composition of the above-ground parts of Astragalus danicus and A. inopinatus collected in the Baikal region (Eastern Siberia) was studied for the first time. From A. danicus, pentacyclic triterpene saponins were isolated and identified, viz., 3-O-(-glucuronopyranosyl)-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-d-xylopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-d-glucopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-l-rhamnopyranosyl)-(12)-O-(-d-xylopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-[O-(-l-rhamnopyranosyl)-(12)-O-(-d-glucopyranosyl)-(12)-(-glucuronopyranosyl)]-3,22,24-trihydroxyolean-12-ene, 3-O-methyl-d-chiro-inositol, and linolenic acid. In A. inopinatus, the same saponins were identified as well as tricosan-1-ol and tetracosan-1-ol, 5,7,4"-trihydroxyflavon (apigenin), and a tetracyclic triterpenoid, 20(R),24(S)-epoxycyclolanost-9(11)-ene-3,6,16,25-tetrol (cycloastragenol). All reported compounds from the both genus of Astragalus were isolated for the first time. Methanolic extracts of A. danicusand A. inopinatus exhibited low inhibitory activity with respect to the growth of HeLa cells. The chloroform fraction of A. danicus showed a strong antimicrobial activity against Staphylococcus aureus and a strong cytotoxic activity against HeLa cells.  相似文献   

8.
Solasodine (I) has been subjected to a number of transformations. The following compounds have been obtained from it by described procedures: 3-acetoxypregna-5,16-dien-20-one (II), 3-acetoxypregn-5-en-20-ol (III), and 3-acetoxypregn-5-en-20-ol (IV). The oxidation of (III) and (IV), the formation of an oxime, and the reduction of the oxime with sodium in ethanol, followed by Hess methylation, has led to 20-dimethylaminopregn-5-en-3-ol (IX) and to 20-dimethylaminopregn-5-en-3-ol (X). From compounds (IX) and (X), by analogy with (III) and (IV) by their oxidation and the preparation of oximes, which were then reduced and methylated, the following were obtained: 3,20-bisdimethylaminopregnane (XVII) and 3,20-bisdimethylaminopregnane (XVIII), and also quaternary salts of the latter.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 370–374, May–June, 1980.  相似文献   

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.
Conclusions A simple route for the synthesis of 1,3,5(10)-estratriene-4.17-diol starting from the accessible 4-estren-17-ol was realized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, p. 655, March, 1972.  相似文献   

11.
The inclusion complexes of -CD with sodium octylsulfonate (C8As), sodium dodecyl sulfonate (C12As), andsodium hexadecyl sulfonate (C16As) in aqueous solutions havebeen studied by surface tension measurement at the air/water interfaceand 1H NMR spectroscopy at 323 K.At fixed concentrations of the surfactants, the surface tensions firstincrease with the increase of -CD concentrations,then they attain a maximum. The surface tension curves of the surfactantsin the presence of -CD are higher than those in the absence of-CD. The values increase with increasing -CD concentrations foreach surfactant. The apparent critical micelle concentrations (CMC) of thesurfactants vary linearly with -CD concentrations.A 1H NMR study shows that the signals of theinner H-3 and H-5 of -CDshift upfield upon addition of the surfactants.The magnitude of the chemicalshift changes (= CD obs)varies as a functionof the concentrations of the surfactants. From therelationships between the chemicalshift changes of H-3 or H-5 inside the -CD cavityand guest/host molar ratios, a 1:1 stoichiometry foreach inclusion complex is assumed. The associationconstants of the inclusion complexes have beendetermined by 1H NMR spectroscopy.  相似文献   

12.
Condensation of (±)-5-allyl-2,3,5-trichloro-4,4-dimethoxy-2-cyclopentenone with phenylethynylmagnesium bromide in THF gave (±)-5-allyl-2,3,5-trichloro-4,4-dimethoxy-1-phenylethynyl-2-cyclopenten-1-ol which chemoselectively reacted with ozone at the terminal double bond, affording (±)-2,3,5-trichloro-5-formylmethyl-4,4-dimethoxy-1-phenylethynyl-2-cyclopenten-1-ol. Oxidation of the latter with H2CrO4 yielded a mixture of the expected product, (±)-5-carboxymethyl-2,3,5-trichloro-4,4-dimethoxy-1-phenylethynyl-2-cyclopenten-1-ol, and anomalous profound oxidation product, (±)-2,3,5-trichloro-5-carboxymethyl-4,4-dimethoxy-1-(2-oxo-2-phenylacetyl)-2-cyclopenten-1-ol. Attempts to remove protective methoxy groups in these compounds under standard conditions were unsuccessful.  相似文献   

13.
Summary 1. Structures have been proposed for - and -reolones (Ia and Ib), two spatial isomers isolated by us previously, as 3,4-dimethyl-2-(4-O-methyl-1--resorcyloyl)-8-oxononan-1,4-olides with the trans-diaxial position of the methine protons in the lactone ring, and with the equatorial orientation of the open chain at C4 in -reolone and the axial orientation in -reolone.2. The possibility has been found of converting -reolone in an acid medium into a 7-methoxy-4-oxodihydrocoumarin derivative at the 3-carbon atom.V. L. Komarov Botanical Institute, Academy of Sciences of the USSR, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 30–38, January–February, 1977.  相似文献   

14.
Results are given which confirm the structure of the furostanol glycoside from tomato seeds forming wastes of the preserving industry. From a butanolic extract of the seeds ofLycopersicum esculentum Mill. we have isolated the furostanol glycoside tomatoside A (I) the structure of which has been established as 25(S)-5-furostan-3,22,26-triol 26-O--D-glucopyranoside 3-O-[O--D-glucopyranosyl-(12)-O--D-glucopyranosyl-(14)--D-galactopyranoside]. At the same time, by enzymatic and chemical transformations three new spirostanol glycosides of neotigogenin have been obtained: tomatoside B (III), which is 25(S)-5-spirostan-3-ol 3-O-[O--D-glucopyranosyl-(12)--D-galactopyranoside], 25(S)-5-spirostan-3-ol 3-O-[O--D-glucopyranosyl-(14)--D-galactopyranoside] (V), and 25(S)-5-spirostan-3-ol 3-O--D-galactopyranoside (IV).Institute of Organic Chemistry, Academy of Sciences of the Kirghiz SSR, Frunze. Institute of the Chemistry of Plant Substances of the Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 533–540, July–August, 1980.  相似文献   

15.
Zusammenfassung N,N-Diphenyl--alanine mit Substituenten in einem oder in beiden Phenylresten wurden durch Umsetzung von entsprechenden Diphenylaminderivaten mit -Propiolacton erhalten. In ähnlicher Weise reagierte Diphenylamin mit -Butyrolacton zu -(N,N-Diphenylamino)-buttersäure. 4,4-Diäthyldiphenylamin und 2-Chlor-6-methyl-diphenylamin wurden als Ausgangsmaterialien für die entsprechenden -Alanine hergestellt.
N.N-Diphenyl--alanines with substituents in one or in both of the phenyl groups were synthesized by reactions of the corresponding diphenylamine derivatives with -propiolactone. Similarly diphenylamine reacted with -butyrolactone to give -(N.N-diphenylamino)-butyric acid. 4.4-Diethyldiphenylamine and 2-chloro-6-methyldiphenylamine were prepared as starting materials for the corresponding -alanines.
  相似文献   

16.
Summary The synthesis of 11 previously unreported dialkyl esters of -mono-, -di-, and -trichloroacetoxy-,,-trichloroethylphosphonic acids has been effected.  相似文献   

17.
By chromatography on Polikhrom-1, silica gel, and Florisil, an ethanolic extract of the digestive organs of the starfishPatiria pectinifera has yielded the steroid polyols 5-cholestan-3,6,8,15,16,26-hexaol and 5-cholestan-3,4,6,7,8,15,16,26-octaol 6-(sodium sulfate). The structures of the compounds have been shown by spectral characteristics and chemical transformations.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 738–741, November–December, 1984.  相似文献   

18.
Five new steroid alcohols have been isolated in the form of their acetates from extracts of the spongeHalichondria sp 1 by column chromatography on silica gel and they have been identified as 24-isopropyl-5-cholest-22z-en-3-ol, 24-isopropylcholesta-5, 22Z-dien-3-ol, 24,24,26,26-tetramethylcholesta-5,25(27)-dien-3-ol, 24,24,26,26-tetramethylcholesta-5,22E,25(27)trien-3-ol, and 24-isopropenyl-25-methylcholesta-5,22E-dien-3-ol. The structures were established by an analysis of spectral characteristics.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 232–239, March–April, 1985.  相似文献   

19.
Summary The dichloride of -ethoxyvinyl-, -isooctyloxyvinyl-, and 2-chloro-3-methylbut-3-enylphosphonous acids have been synthesized and characterized for the first time. The diethyl ester of -ethoxyvinylphosphonous acid has been-obtained from the dichloride of -ethoxyvinylphosphonous acid.  相似文献   

20.
Zusammenfassung Das feste -Carotin ist gegen -Strahlung ziemlich stabil. Bei Bestrahlung unter Sauerstoffbegasung treten deutliche -Carotin-Verluste erst bei der hohen Dosis von 12 Mrad auf; bei Bestrahlung an der Luft werden ähnliche Radiolyseerscheinungen erst durch wesentlich höhere Strahlendosen ausgelöst. Spaltungsprodukte, die bei 12 Mrad und Sauerstoffbegasung auftraten und dünnschichtchromatographisch aufgetrennt werden konnten, waren Isozeaxanthin, -Carotin-5,6-5, 6-diepoxid, -Carotin-5,8-5,8-diepoxid, -Apo-12-carotinal, -Apo-10-carotinal, 3,3,6-Trihydroxy--carotin-5,8-epoxid und Vitamin-A-Alkohol. Es ist bemerkenswert, daß ein Teil der Radiolyseprodukte (z. B. Vitamin-A1-Alkohol, -Apo-12-carotinal und -Apo-10-carotinal) Vitamin-A-Wirksamkeit besitzt.
The -Irradiation of synthetic -carotene. Some physico-chemical and thin-layer chromatographic studies of radiolysis products
Solid -carotene is remarkably stable to -irradiation. In an oxygen atmosphere doses as high as 12 Mrad were required to bring about significant losses of -carotene, whereas in air even larger doses had to be applied in order to effect a comparable degree of radiolysis. Cleavage products which arose in O2 at a dose of 12 Mrad and which could be separated from each other by thin-layer chromatography were isozeaxanthin, -carotene-5,5-5,6-diepoxide, -apo-12-carotenal, -apo-10-carotenal, 3, 3, 6-trihydroxy--carotene-5,8-epoxide and vitamin A1. It is notable that some of the radiolysis products (e.g., vitamin A1, -apo-12-carotenal and -apo-10-carotenal) possess vitamin A activity.


Herrn Prof. Dr.O. Hromatka zum 65. Geburtstag gewidmet.  相似文献   

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