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1.
One- and two-dimensional homo- and heteronuclear correlation proton, carbon, proton—proton, and proton—carbon NMR spectra of fifteen drimanic sesquiterpenoids: 11,12-dibromodrima-5,8-dien-7-one, drim-8-en-7-one, 11-hydroxydrim-8-en-7-one, 11,12-dihydroxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 11-hydroxy-11,12-epoxydrim-8-en-7-one, 8,9-epoxydriman-7-one, 8,9-epoxydriman-7-ol, 11,12-diacetoxydrim-8-en-7-ol, drimane-7,8,11-triol, 7,8-isopropylidenedioxydriman-11-al, 9, 11-dihydroxydrim-7-en-6-one, drimane-7,8,9-triol, drimane-7,8,11-triol, and drim-8-ene-7,11,12-triol were studied. The proton and carbon chemical shifts were assigned.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2589–2594, December, 2004.  相似文献   

2.
,-Dibromo--('-carbethoxyacetony)-,-butenolide (I) reacts with amines in diethyl ether solution to give -bromo-amino--('-carbethoxyacetony)-,-butenolides. Compounds n are converted to -bromo-amino--('-carbethoxyacetony)-,-butenolides on reaction with amines. The corresponding arylhydrazones (VI and VII) are obtained by the reaction of I and II with p-nitro- and 2,4-dinitrophenylhydrazines. Compound I reacts with phenylhydrazine to give furopyridazine VIII.See [1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 867–871, July, 1972.  相似文献   

3.
Summary The acyl -D-glucopyranoside, the acyl -D-xylopyranoside, the acyl D- and L--arabinopyranosides, and the acyl -D-lactoside of 18-glycyrrhetic acid, and also the acyl -D-lactoside of 18-glycyrrhetic acid have been synthesized. The acid and alkaline hydrolysis of the compounds obtained has been studied.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 1, pp. 13–19, 1968  相似文献   

4.
Summary A comparative discussion of the signals in the13C NMR spectra of acetylated methyl - and -D-xylopyranosides, - and -D-glucopyranosides, - and -D-galactopyranosides, - and -L-arabinopyranosides, - and -L-fucopyranosides, and - and -L-rhamnopyranosides and of the corresponding free glycosides has shown a similarity of the effects of substitution at C5 with a longer-range nature of these effects in the case of the acetylated glycosides.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. 1, pp. 6–8, January–February, 1979.  相似文献   

5.
A radiochemical charged particle activation procedure for the simultaneous production of carrier-free radioisotopes of more than one element in a single target and their subsequent separation through LLX has been demonstrated. The carrier free isotopes,95,96Nb,93,94,95,96,99mTc and94,95,97,103Ru formed through Mo(,pxn), Mo(,pxn) and Mo(,xn) nuclear reactions with 40 MeV -particle as detected by nondestructive -ray spectroscopy, have been effectively separated through LLX using TOA as an anionic extractant. Separation of the bulk matrix of molybdenum from the carrier free products has been monitored radiometrically using isotopic93,99mMo formed through the Mo(,xn) reaction, as radioindicators for the target element. Purity of the separated carrier free radionuclide has been verified by -ray spectrometry.  相似文献   

6.
Zusammenfassung Es wird über die Synthese von N-(-Aminoacyl)-p-toluolsulfonamiden und N-(-Aminoacyl)-methansulfonamiden berichtet, deren Acylreste sich vonl-Tyrosin,d,l--Methyl-tyrosin undd,l-3,4-Dihydroxy-phenylalanin ableiten.
The synthesis of N-(-aminoacyl)-p-toluenesulfonamides and N-(-aminoacyl)-methanesulfonamides containing the acyl groups ofl-tyrosine,d,l--methyltyrosine andd,l-3,4-dihydroxy-phenylalanine is described.
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7.
Summary 1. The synthesis of L-(+)--oleoyl--linoleoyl--glycerylphosphorylethanolamine has been effected.2. During the investigations the following substances were isolated and characterized: L--oleoyl--glycerylphosphoryl-N-phthaloylethanolamine and L---linoleoyl--glycerylphosphoryl-N-phthanoylethanolamine.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 2, pp. 80–83, 1966  相似文献   

8.
Conclusions When heated in the presence of a catalytic amount of BF3 etherate,-trifluoromethyl--diethylamino--fluoroacrylic acid N, N-dimethylamide is reversibly isomerized to-trifluoromethyl--dimethylamino--fluoroacrylic acid N, N-diethylamide. The methyl esters of-trifluoromethyl--diethylammo--fluoroacrylic acid and-trifluoromethyl--phenoxy--fluoroacrylic acid N,N-dimethylamide are not isomerized under the same conditions.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No.1, pp.137–141, January, 1976.  相似文献   

9.
Conclusions A culture ofActinomyces roseochromogenus ATCC 3347 reduces 17-hydroxy- and 16, 17-epoxy-20-oxopregnenes to the corresponding 20-alcohols, but is incapable of reducing 17-acetoxy-, 17-methyl-, and 16-methylprogesterones or 17-unsubstituted 20-oxopregnenes. The results obtained show that the presence of the side chain in a conformation favorable for the formation of 20-alcohols in the reduction of 20-oxosteroids with complex metal hydrides is in itself insufficient for the reduction of the 20-oxosteroids by a culture ofActinomyces roseochromogenus, which also reduces the 20-oxo group of 17-pregnenes.Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 38–47, 1970  相似文献   

10.
An increase in the number of titration cycles results in a considerable decrease in HT and OT values, which in turn, brings about a decrease in the amount of desorbed hydrogen. This shows that water, being a product of titration reaction, is adsorbed on the oxidized surface of rhodium and represents a kinetic-diffusive barrier for hydrogen titration.
, HT OT, , , . , , , , , - .
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11.
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   

12.
Circulardichroismspectra of 5- and 7-bromo-6-ketosteroidsof the cholestane and stigmastane serieswere studied. A negative Cotton effect corresponding to the n-* -transition of the ketone was observed in the CD spectra of 5-bromo-6-ketosteroids at 300 nm. The analogous Cotton effect was positive in CD spectra of 7-bromo-6-ketosteroids.  相似文献   

13.
The new steroidal alkaloid sevedinine was isolated from the aerial part of Korolkovia severtzovii. The structure of sevedinine wasestablished as 6,12-dihydroxy-5-cevanin-3-one using spectral data, chemical transformations, and an x-ray structure analysis. The location of the tertiary hydroxyl in ten cevine alkaloids from Korolkovia severtzovii was corrected based on the results.  相似文献   

14.
    
Zusammenfassung Im Rahmen von Untersuchungen zur Bromierung von Propiophenon wurde eine infrarotspektrophotometrische Methode zur Bestimmung von -Brompropiophenon in Gegenwart von -Dibrompropiophenon und Propiophenon entwickelt. Die Methode ist genau und schnell. -Brompropiophenon und -Dibrompropiophenon wurden erstmalig durch ihre Infrarotabsorptionsspektren chatakterisiert.
Summary In the course of investigations on the bromination of propiophenone an infra-red spectrophotometric method has been developed for the determination of -bromopropiophenone in the presence of -dibromopropiophenone and propiophenone. The method is precise and rapid. -Bromopropiophenone and -dibromopropiophenone have been characterized by their infra-red absorption spectra for the first time.
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15.
From the leaves of Algerian ivyHedera canariensis Willd. (fam. Aralaceae) we have isolated 13 triterpene glycosides: the 3-O--L-arabinopyranosides of oleanolic acid (A), of echinocystic acid (B1), and of hederagenin (B2); the 3-O-[O--L-rhamnopyranosyl-(2)--L-arabinopyranoside]s of oleanolic acid (C), of echinocystic acid (D), and of hederagenin (E1); the 3-O--L-rhamnopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--gentiobioside of hederagenin (G1); the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside] 28-O--gentiobioside of hederagenin (G3); the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--gentiobioside]s of oleanolic acid (G2), of echinocystic acid (H1), and of hederagenin (H2); the 3-O-[O--L-rhanmopyranosyl-(12)--D-glucopyranoside] 28-O-(O--L-rhamno-pyranosyl-(14)--gentiobioside] of hederagenin (H2); and the 3-O-(O--L-rhamnopyranosyl-(12)-O-gentiobiosyl)-O-(14)--L-rhamnopyranosyl-(12)-a-L-arabinopyranoside] of hederagenin (G4). The structures of the substances isolated have been established on the basis of chemical transformations and13C NMR spectroscopy.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 377–383, May–June, 1996. Original article submitted December 3, 1995.  相似文献   

16.
The reaction of methyl -methoxy-, -acetoxy-, and -chloroacrylate with diazomethane proceeds in conformity with the -M orienting effect of the ester group. The resulting 1-pyrazolines are converted to 3(5)-carbomethoxypyrazole at room temperature (the reaction proceeds more readily on heating).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 545–546, April, 1973.  相似文献   

17.
The dependence of palladium distribution in zeolites on the temperature of thermal treatment has been established from the data on oxygen chemisorption and the statistical processing of electron micrographs. The influence of palladium distribution in zeolites on their catalytic activity towards the complete oxidation of benzene has been shown.
- . .
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18.
Zusammenfassung Die Synthese von 3, 16-Diacetoxy-5 -pregnan-20-on (VI) aus 3-Acetoxy-5 -pregn-16-en-20-on und eine verbesserte Darstellung von 3, 16-Diacetoxy-5 -pregnan-20-on (III) aus 3-Acetoxy-pregna-5, 16-dien-20-on werden beschrieben.  相似文献   

19.
Several halomethyl-arylcarbinols were prepared, and the influence of substituents on enantiomer selectivity in the acetalisation reaction with [2S-(2,3a,4,7,7a)]-octahydro-7,8,8-trimethyl-4,7-methanobenzofuran-2-ol was examined.
Unserem sehr verehrten Lehrer, Herrn Prof. Dr.Otto Hromatka, mit den besten Wünschen zum 80. Geburtstag gewidmet.  相似文献   

20.
Conclusions The reduction of the ethyl esters of- and'-oxodehydrodesthiobiotin with sodium borohydride, and subsequent treatment of the intermediate hydroxy esters with thioacetic acid, gave the ethyl esters of- and'- (aceitylmercapto)dehydrodesthiobiotin.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2626–2627, November, 1973.We express our gratitude to V. V. Filippov for running the biological tests on (V), (VI) and (XI).  相似文献   

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