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1.
Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966  相似文献   

2.
Oxidation of tricyclic sesquiterpenoids of the caryophyllene type with the HBr—DMSO system afforded ,-unsaturated -bromoketones. Since tricyclic derivatives, unlike simple alicyclic ketones, cannot undergo aromatization, all intermediate oxidation products can be isolated, which provide evidence that oxidation proceeds according to the following scheme: ketone-bromoketone,-dibromoketone,-unsaturated -bromoketone.  相似文献   

3.
We have determined the spectroscopic characteristics, the dipole moments, and the Kerr constants of the stereoisomers of the secondary-tertiary diols of the cyclohexane and bicyclo [4.1.0]pentane series: 3,4-dihydroxy-3-carane (I), 3,4-dihydroxy-3-methylnorcarane (II), 3,4-dihydroxy-3-methylnorcarane (III), 4, 5-dihydroxy-3-methylcyclohexene (IV), 3,4-dihydroxy-3-carane (V), 3,4-dihydroxy-3-methylnorcarane (VI), 3, 4-dihydroxy-3-carane (VII), and 3,4-dihydroxy-4-methyl-3-carane (VIII). It was found that the cis diols are more polar than their trans isomers. It was shown by electrical and electrooptical methods that rotamers with a gauche orientation with respect to the tertiary C-O are stable relative to those containing the diol at the ordinary C-C bond of the ring.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 619–625, March, 1991.  相似文献   

4.
Summary The synthesis of the following 1, 4-diphosphoinositides has been effected: the - (, -distearoyl) glyceryl ester of myoinositol 1, 4-diphosphate (VI) or (VII) and 1, 4-bis-[ - (, -distearoyl) glycerylphosphoryl] myoinositol (VIII).Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 230–233, 1966  相似文献   

5.
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   

6.
The epithermal neutron spectrum shape parameter in nuclear reactors is explained from a theoretical point of view in terms of the neutron slowing down density function. The latter is approximated by Fermi's age theory. Values for are calculated for a simple approximation of a nuclear reactor: a disk shaped fission neutron source in an infinite graphite moderator. The model produces -values with the correct sign and magnitude, compared to experimental values from the literature, determined in a real reactor. It is shown that varies strongly with distance to the neutron source and less strongly with neutron energy. The inappropriateness of average -values, obtained from the slope of quasi-straight lines produced by log-log plots of E versus E, for the correction of non-ideal epithermal neutron activation is discussed. Conclusions are formulated concerning the impact of an energy dependent on comparator type NAA.  相似文献   

7.
The reaction of ketoximes with hypophosphorous acid resulted in previously unknown -substituted--aminophosphinic acids, which were oxidized into the corresponding -substituted--aminophosphonic acids.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2729–2732, November, 1996.  相似文献   

8.
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   

9.
Monosubstituted - and -alkylthiophans and -, -, and -alkylthiacyclohexanes were subjected to a comparative mass spectrometric study. The stability of the M+ ion increases on passing from - to -alkylthiophans and from - to - and -alkylthiacyclohexanes. In the case of -alkylthiophans and - and -alkylthia-cyclohexanes the principal process is associated with ejection of the substituent as a whole, whereas a portion of the alkyl substituent, with retention of one CH2 group in the composition of the charged fragment, is eliminated from the molecular ions of -alkylthiophans and -alkylthiacyclohexanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 176–181, February, 1978.  相似文献   

10.
A radiochemical charged particle activation procedure has been developed for the production and separation of the carrier free radioisotopes,65Zn and66,67,68Ga. The carrier free radioisotopes produced by the irradiation of a pure copper foil with 50 MeV -particle beam through the nuclear reactions, (, pxn), (,pxn) and (,xn), have been quantitatively separated from the activated copper matrix from an aqueous hydrochloric acid and an alkaline solution using the liquid cation exchanger HDEHP, as an extractant. Detection of different radionuclides in the activated copper target and verification of their purity at different stages of their LLX separation have been performed by -ray spectrometric studies.  相似文献   

11.
Silica-containing -zirconium phosphate (-ZrSiP) was prepared by the precipitation method. X-ray diffractometry was used to characterize -ZrSiP and to compare it with other -zirconium phosphates (ZrP). A monoclinic cell with parameters of a=0.9038 nm, b=0.529 nm, c=1.4183 nm and =91.76° was identified for -ZrSiP, i.e. silica modifies the original -ZrP structure. The specific surface area of -ZrSiP was found to be two orders of magnitude higher then that of -ZrP.  相似文献   

12.
The authors present some theoretical considerations concerning the influence of the form of the conversion functionf() on the values of the degree of conversion corresponding to the maximum value of the reaction rate (max) as well as on the inflexion points (inf) of the DTG curve. The obtained equations are characterized by a general validity no matter the form off().
Zusammenfassung Es werden einige theoretische Überlegungen bezüglich des Einflusses der Form der Konversionsfunktionf() auf die Werte der Konversionsrate bei maximalen Reaktionsgeschwindigkeiten (max) sowie auf Inflexionspunkte () der DTG-Kurve angestellt. Die erhaltenen Gleichungen sind unabhängig von der Form vonf() durch eine all-gemeine Gültigkeit charakterisiert.
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13.
The paper is devoted to the synthesis of steroidal 5-hydroxy-6-oxolactones from ethyl esters of 5,6-dienic acids. By epoxidating the latter it has been shown that, in addition to the usual formation of 5,6-oxides, opening of the 16, 17-oxide ring initially formed takes place and this is accompanied by intramolecular cyclization to a 17,20-dihydroxy--lactone. The trans-opening of the 5,6-epoxide in the epoxy--lactone and subsequent oxidation with N-bromosuccinimide has led to a new representative of steroidal -lactones — the 23,16--lactone of the 3-acetate of 3, 5, 16, 17, 20-pentahydroxy-6-oxo-24-norcholan-23-oic acid.N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences of the USSR, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 208–213, March–April, 1980.  相似文献   

14.
Conclusions It has been established that patrinoside C1 is -D-xylopyranosido(1 2)--D-glucofuranosido(1 3)--L-rhamnopyranosido(1 3)oleanolic acid.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 1, pp. 22–26, 1969  相似文献   

15.
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   

16.
Conclusions An efficient method for the synthesis of ,,-trihydropolyfluoroalkyl chlorophosphates is by reacting ,,-trihydropolyfluoroalkyl dichlorophosphites and bis-(,,-trihydropolyfluoroalkyl) phosphites with sulfuryl chloride. It has been found that in three-coordinated polyfluoroalkyl phosphites, the high electronegativity of the polyfluoroalkyl groups hinders cleavage of the latter on reaction with sulfuryl chloride, thereby facilitating the formation of oxidation products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 146–149, January, 1988.  相似文献   

17.
In the decomposition of ,-dimethylbenzyl hydroperoxide (1) by use of copper(II) chlorocomplexes, the novel fact was found that the product ratio of acetophenone (2) to ,-dimethylbenzyl alcohol (3) is 2 to 1. The kinetics of this result was investigated and a mechanism consistent with the experimental result is proposed.
Mechanismus der Zersetzung von ,-Dimethylbenzylhydroperoxid unter Bildung von Acetophenon und ,-Dimethylbenzylakohol in einem konstanten Verhältnis von 2:1
Zusammenfassung Bei der Zersetzung von ,-Dimethylbenzylhydroperoxid (1) unter Verwendung eines Kupfer(II)chlorkomplexes wurde die neue Feststellung gemacht, daß das Produktverhältnis Acetophenon (2): ,-Dimethylbenzylalkohol (3) stets 2:1 ist. Die Kinetik der Reaktion wurde untersucht und ein Mechanismus vorgeschlagen, der mit dem experimentellen Resultat konsistent ist.
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18.
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   

19.
Two new glycosides, gomphotin (1) and gomphotoxin (13), and also the known gomphoside (9) have been isolated from the leaves ofGomophocarpus fruticosus. Compounds (1) and (9) contain a 4,6-dideoxyhexosulose residue as the sugar component, and (13) a 6-deoxyhexosulose, which are attached to glycolic OH groups of the aglycons by 3-O-1,2-O-2 (9, 13) and 3-O-1,4-O-2 (1) acetal-ketal bonds. The structures of the new compounds are represented by the names (3-O-1,4-O-2)-(2,3-dihydroxy-4, 6dideoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (1) and (3-O-1,2-O-2)-(2,3,4-trihydroxy-6-deoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (13).State Scientific Center for Drugs of the Ministry of Health and the National Academy of Sciences of the Ukraine, Kharkov, fax 441118. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 824–832, November–December, 1995. Original article submitted May 22, 1995.  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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