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1.
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   

2.
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   

3.
The reaction of hydrazides of adenylyl- or hypoxanthinyl-9-alkylcarboxylic acids with sodium nitrite in acid media gives reactive azides of purinyl-9-alkylcarboxylic acids which condense with ()-aminocarboxylic and ,-diaminocarboxylic acids to give N(N)-(adenylyl-9-alkanoyl) aminocarboxylic, N-(adenylyl-9-)- and N-(hypoxanthinyl-9-alkanoyl)-,-diaminocarboxylic acids. The deamination of N-(adenyl-yl-9-alkanoyl)aminocarboxylic acids gives N-(hypoxanthinyl-9-alkanoyl)aminocarboxylic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 126–130, January, 1985.  相似文献   

4.
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   

5.
1,3-Skeletal rearrangement of N-substituted ketimines via a possible intimate ion pair is discussed. (CH3)3SiCH=C=O (1) reacts with N-(aziridinyl)-triphenylphosphinimine (2) to give N-(1-aziridinyl)-2-trimethylsilylketen-1-imines (3). The compounds3 b, c are thermally labile and do not undergo 1,3-rearrangement but a retro-ene type reaction to yield (CH3)3SiCH2CN and 2,3-diphenyl-2H-azirine (4). Diphenylketene (5) reacts with N-(N, N-dialkylamino)-triphenylphosphinimines (6) to yield -(N-disubstituted-amino)-nitriles (7). , -Dimethyl--(triphenylphosphinimino)-acetonitrile (9) reacts with (5) at room temperature to form , -dimethyl--(2, 2-diphenylketen-1-imino)-acetonitrile (10) which rearranges at 80° to dimethyl diphenylsuccinonitrile (11). The reaction of5 with 7-(triphenylphosphinimino)-7-azabicyclo[4.1.0]heptane (12) gives tetraphenylsuccinonitrile13 and 7-(7-azabicyclo[4.1.0]heptane)-, -diphenylacetonitrile (14). Finally the synthesis of N-acylketenimines (16) from (5) and acyltriphenylphosphinimines (15) is reported.

38. Mitt.:Chr. Ivancsics undE. Zbiral, Mh. Chem.106, 839 (1975).  相似文献   

6.
    
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   

7.
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   

8.
Diphasic boehmite derived unseeded and seeded (by either -Al2O3, -Fe2O3, or Fe(NO3)3) alumina gel planar monoliths were examined by DTA, XRD and photoluminescence spectroscopy. Luminescence spectra enable sensitive monitoring of the - and -Al2O3 crystallization in heat-treated gels due to Cr3+ impurity traces. Fe(NO3)3 unlike other seeds effectively influences crystallization of both - and -Al2O3. The present results are interpreted as prevailing solution or Fe3+ ion effect on the crystallization process.  相似文献   

9.
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   

10.
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   

11.
Summary The synthesis of racemates of the 2-methyl, 4-methyl, 17-methyl, and 2, 17-dimethyl derivatives of 19-nor-D-homotestosterone has been described. Biological tests have shown that the introduction of a CH3 group into positions 2 and 17 totally suppresses both androgenic and anabolic activity. The introduction of a CH3 group into position 4 leads to a divergence of the anabolic and androgenic effects.Khimiya Prirodnykh Soedinenii, Vol. 4, No. 1, pp. 3–9, 1968  相似文献   

12.
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   

13.
Zusammenfassung -Äthyl--phenylacetessigester (I) wurde bromiert, der resultierende -Bromacetylphenylbuttersäureester (II) mit NaBH4 zum Bromhydrin (III) reduziert. Umsetzung mit KCN lieferte den -Cyan--hydroxy--phenyl--äthylbuttersäureester (IV), der in Gegenwart vonRaney-Ni zu den beiden stereoisomeren 3-Äthyl-3-phenyl-4-hydroxypiperidonen-(2) (Va) und (Vb) reduziert wurde. Oxydation von (Vb) mit CrO3 lieferte das 3-Äthyl-3-phenylpiperidindion-(2,4) (VI).  相似文献   

14.
A survey of top soil environmental radioactivity in Akwa Ibom State of Nigeria has bean investigated. The results vary considerably from one environment to another ranging between a minimum of 161 mBq·g–1 and a maximum value of 648 mBq·g–1 -activity. The work reveals that hospitals and health centres lead in top soil radioactivity with the highest mean values of (378 mBq·g–1) and (294 mBq·g–1) followed closely by industrial areas with mean values of (372 mBq·g–1) and (283 mBq· g–1) trailing beaches and recreation centres having average values of (364 mBq·g–1) and (273 mBq·g–1). Lower levels of top soil radioactivity were observed mostly in environments with high level human interaction activity such as schools, offices, environments and recreation centres. An overall top soil mean of 342 mBq·g–1 -activity, 271 mBq·g–1 -activity and 71 mBq·g–1 -activity were observed in the State.  相似文献   

15.
Zusammenfassung Für die Synthese von 5,5-Diphenyl-3-hydroxy-hydantoin wird ,-Diphenyl-glycin mit COCl2 in das Leuchs-Anhydrid übergeführt, welches mit O-Benzyl-hydroxylamin das ,-Diphenylglycin-benzyloxyamid ergibt. Cyclisierung mit COCl2 führt zum Hydantoinring. Die O-Benzylgruppe wird mit HBr in Eisessig oder durch katalytische Hydrierung entfernt. Die IR- und UV-Spektren der Titelverbindung sowie ihr pK A-Wert werden angegeben. Versuche, die Titelverbindung zu einem Nitroxid-Radikal zu oxidieren, schlugen fehl; sie zeigt keine antiepileptische oder antikonvulsive Wirksamkeit.
5.5-diphenyl-3-hydroxy-hydantoin
The synthesis of 5,5-diphenyl-3-hydroxy-hydantoin is reported. ,-Diphenyl-glycine is treated with phosgene to give a Leuchs anhydride, which in turn is reacted with O-benzyl-hydroxylamine to form the ,-diphenyl-glycine-benzyloxyamide. Cyclisation to the hydantoin is effected with COCl2. Finally the O-protecting group is removed by either HBr in acetic acid or catalytic hydrogenation. The IR-and UV-spectra and the pK A-value of the title compound are reported. Attempts to oxidize the title compound to a nitroxide-radical failed. The title compound shows no antiepileptic or anticonvulsive activity.


Meinem verehrten Lehrer, Herrn Prof. Dr.H. Bretschneider, zum 65. Geburtstag gewidmet.  相似文献   

16.
,-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   

17.
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   

18.
The phase diagram of the system Ag4SSe-SnTe is studied by means of X-ray diffraction, differential thermal and metallographic analyses and measurements of the microhardness and the density of the material. This diagram is divided into two eutectic-type subdiagrams by the composition Ag4SSe·2SnTe. The unit-cell parameters of the intermediate phases 3Ag4SSe·SnTe (phase A) and -Ag4SSe·2SnTe (phase B) are determined as follows: for phase A: a=0.7851 nm, b=0.7196 nm, c=0.6296 nm, =101.32°, =85.90°, =111.36°; for phase B: a=0.3662 nm, b=0.3303 nm, c=0.3343 nm, =90.74°, =108.94°, =91.91°. The phase Ag4SSe·2SnTe melts congruently at 615°C and a polymorphic transition of the phase takes place at T - =110°C.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
In a continuation of the research on use of 20-keto-16,17-epoxysteroid 20-hydrazones for synthesis of 17-thio analogs of 20-ketosteroid 16,17-acetonides [2, 3], we synthesized 5-H-pregnane-3,16,21-trihydroxy-17-thiol-20-one 16,17-acetonide and found methods for its microbiological dehydrogenation and hydroxylation into 4-3-keto-and 9-hydroxy-4-3-keto derivatives.See [1] for Communication 188.N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, 117913 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 5, pp. 1182–1186, May, 1992.  相似文献   

20.
Chiral [6R and 6S-(6, 9, 10)]methano-1H-cyclooct[b]indol-9-ols were segregated into enantiomers through diastereomeric esters with (R)--trifluoromethylphenylacetic acid. The absolute configuration of the enantiomers was established by the NMR method using the shift reagent Eu(fod)3 and the circular dichroism spectra.  相似文献   

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