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1.
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   

2.
Summary 6,6-Methylenebisdeoxyvacisinone and its homologs have been synthesized by the reaction of methylenebisanthranilic acid with lactams (-butyrolactam, -valerolactam, -caprolactam, and -chloro- and ,-dichloro--caprolactams). The condensation of anthranilic acid and its derivatives (4-nitro-, 5-bromo-, 5-iodo-, and 5-nitroanthranilic acids) with ,-dichloro--caprolactam has given seven-membered analogs of deoxyvasicinone containing two chlorine atoms in the polymethylene ring.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 544–547, July–August, 1977.  相似文献   

3.
The previously known triterpenoid 3-O--L-arabinopyranosides of oleanolic and echinocystic acids and hederagenin, 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranosides of oleanolic acid and hederagenin, in addition to 28-O--L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl ethers of the 3-O--L-arabinopyranoside of hederagenin, and 3-O--D-glucopyranosyl-(12)-O--L-arabinopyranosides of oleanolic acid and hederagenin, respectively, are isolated from leaves ofFatsia japonica(Araliaceae). The structures of the glycosides are confirmed by chemical methods and 13 C NMR spectroscopy  相似文献   

4.
A study of the extraction of polonium from aqueous solutions containing -hydroxyisobutyric acid (-HIBA) was performed with four different extractants, di-n-octyl sulphide (DOS), Cyanex 272, Cyanex 301 and Cyanex 302, dissolved in toluene. The extracted complex for DOS at low -HIBA concentrations is most likely PoO(-HIB)2·2DOS, while at higher -HIBA concentrations there seems to be a solvating effect implicating an extracted complex of the type PoO(-HIB)2(-HIBA)2·2DOS. For the extraction of polonium with Cyanex 272 the results are inconclusive. The extracted complex is either PoOA2 or PoO(-HIB)2·2HA. For extraction with Cyanex 301 or Cyanex 302 the major extracted species does not contain any -HIBA molecules. The neutral species in both cases is PoOA2, extracted at low extractant concentrations, while at higher extractant concentrations a complex of the type PoOA2·xHA is extracted. The extraction of polonium increases in the order Cyanex 272 < DOS < Cyanex 302 < Cyanex 301.  相似文献   

5.
It was found that opening of the isoxazolidine ring of 6a-isopropenyl-1/-trimethylsilyloxy-3, 3a,4,5,6,6a-hexahydro-(1H)-cyclopent[c]isoxazoles by the F ion initially gives an intermediate, a tertiary nitrosocompound detected by UV and NMR spectroscopy. Its transformation, finally, into ,-unsaturated aldoximes probably involves an unprecedented allylic migration of the nitroso group.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 461–464, March, 1994.  相似文献   

6.
Conclusions The triterpene glycosides scabiosides D, E, F, and G have been isolated from the roots ofPatrinia scabiosofolia Fisch. et Link. It has been established that scabioside D is O--D-glucopyranosyl-(1 4)-O--L-arabopyranosyl-(1 3)-O-oleanoloyl-(28 1)--D-xylopyranose, and scabioside E is O--D-glucopyranosyl-(1 4)-O--L-arabopyranosyl-(1 3)-O-oleanoloyl-(28 1)-O--D-xylopyranosyl-(4 1)--L-rhamnopyranose.  相似文献   

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.
Cyclosiversigenin 6-O--L-rhamnopyranoside and 6-O--D-glucopyranoside were isolated fromAstragalus coluteocarpusBoiss. (Leguminosae) andAstragalus dissectusB. Fedtsch. et N. Ivanova, respectively. Cyclosiversigenin 5-O--L-rhamnopyranoside was shown to be an artifact forAstragalus coluteocarpus.Thus, the cyclosiversigenin 6-O--D-glucopyranoside that was isolated from certainAstragalusspecies is hypothesized also to be an artifact. Glycosylation of the 6 -hydroxyl group of cycloartanes by D-glucose and D-xylose, in contrast with other substituents, does not change the low-field position of the PMR signal of the 4-CH 3 group (1.65 2.01 ppm) that is caused by the influence of deuteropyridine directly on the 6 -hydroxyl. Obviously one of the hydroxyls of the -D-glucopyranoside or -D-xylopyranoside residues has the same effect in this instance.  相似文献   

9.
Phase transition of metastable -FeOOH into -FeOOH and its chemical transformation into -Fe2O3 upon hydrothermal treatment in 0-5 M NaOH solutions at 100-230°C were studied. The regions of formation of the above phases were specified. The probable composition of the crystallizing complexes formed in the solutions and the reactions occurring at their incorporation into various atomically smooth faces of -FeOOH and -Fe2O3 were considered.  相似文献   

10.
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   

11.
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   

12.
Conclusions The reaction of diethylamine, piperidine, ethylenimine, and cyclohexylamine with ethyl-fluoroacrylate, and also of ethylenimine with phenyl-fluorovinyl ketone, leads to the addition of the amines to the-fluorovinyl group with the formation of-fluoro--aminopropionic acid derivatives.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicneskaya, No. 10, pp. 2362–2363, October, 1975.  相似文献   

13.
The effect of representing dielectric properties in terms of the complex polarizability c = – i is examined. Loss curves ( and tan ) are shifted towards higher frequencies, revealing the existence of new relaxations and allowing the clarifications of ones already known. We have calculated the shift ratios (at maximum or tan )/ (at maximum or tan ) from the more conventional empirical equations representing the dielectric behavior. Some examples are given.  相似文献   

14.
The action of N-methylpiperazine and , -dimethylpyrrolidine on chloroacetyl derivatives of phenylhydrazides of diaryl- and dialkylglycolic acids has given the previously unknown N-methylpiperazinoacetyl and , -dimethylpyrrolidnoacetyl derivatives of these phenylhydrazides.For part XL, see [1].  相似文献   

15.
Summary 1. A method for the separation and quantitative determination of - and -DNP derivatives of , -DABA, ornithine, and lysine has been proposed.2. A quantitative evaluation of the N N migration in four peptides of , -DABA has been carried out.3. The degree of migration in inactive polymyxin M and the DNP-peptides from a partial hydrolyzate of the inactivated antibiotic has been determined.4. The amino acid composition of the DNP peptide B1 from a partial hydrolyzate of active DNP-polymyxin M has been established.5. The quantitative aspect of the conversion of and diketopiperazines has been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 277–284, 1966  相似文献   

16.
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   

17.
Conclusions On the basis of the rates of their acid hydrolysis, their optical activities, and their IR spectra, it has been established that the glycosides ofAesculus hippocastanum L. are (SK-1) 3--L-arabofuranosyloxy-5,7,4-trihydroxyflavone, (SK-2) 3--L-rhamnofuranosyloxy-5,7,4-trihydroxyflavone, (SK-3) 3--L-arabofuranosyloxy-5,7,3,4-tetrahydroxyflavone, and (SK-4) 3--L-rhamnofuranosyloxy-5,7,3,4-tetrahydroxyflavone.The glycoside SK-3 is identical with avicularin isolated from the leaves ofPsidium quajava [5]. The complete structures of the other three glycosides have been established for the first time.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 1, pp. 5–7, 1969  相似文献   

18.
,-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   

19.
    
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.
  相似文献   

20.
Summary Depsipeptides containing -hydroxy -amino acid residues as hydroxy-acid component were synthesized.Communication 11 of the series -Substituted -Amino Acids.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 1987–1992, November 1965  相似文献   

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