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1.
Eight new molecular compounds between -1,2,3,4,5,6-hexachlorocyclohexane (-HCH) and some heterocyclic salts (hydrochlorides of - and -picoline, 2,4,6-collidine, ,-bipyridine, isoquinoline, acridine, 9-phenylacridine, and 2,4,6-triphenylpyrylium perchlorate), with the molecular ratio 12, were synthesised and described by means of spectroscopic (IR, UV, NMR) and X-ray-diffraction methods. Some of the molecular compounds may be used for quantitative separation of the heterocyclic salts from complex mixtures.

Lehrstuhl für Mineralogie.  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.
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   

4.
The Reformatsky reaction with 4-azafluorenone has given 9-hydroxy-9-(-alkoxycarbonylalkyl)-4-azafluorenes. The course of this reaction with respect to the -haloester used, and the conversion of these hydroxyesters into hydroxy- and ,-unsaturated acids have been examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 81–85, January, 1991.  相似文献   

5.
Using a crystal model with an adsorbed layer, the propagation of vibrational excitation induced by an adsorbed particle is considered. The relaxation times of excitation have been estimated. The role of excitation transfer processes in adsorption-desorption phenomena is discussed.
, . . - .
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6.
Summary A GC-MS method has been studied for characterization and quantification of phytosterols, cholesterol and cholesterol oxidation products. Baseline separations have been achieved between cholesterol, cholesterol 5-6-epoxide, 5-cholestene-3-ol-7one (7-keto-cholesterol), cholestene-3-5-6-triol, 5-cholestene-3-25-diol (25-hydroxycholesterol), 5-cholestene-3-20-diol (20-hydroxycholesterol), 5-cholestene-3-7-diol (7-hydroxycholesterol) and 5-cholestene-3-19-diol (19-hydroxycholesterol) as well as between -cholestane, cholesterol, stigmasterol, campesterol and -sitosterol. Excellent linearity of response has been obtained permitting reliable quantification. The characterization of each derivatized sterol has been performed by mass-spectrometry. The results confirm the utility of combined gas chromatography-mass spectrometry in the analysis and characterization of sterols and cholesterol oxidation products.  相似文献   

7.
Pyrylium salts with a free (active) position and different kinds of substituents in the, positions of the pyrylium ring were obtained by the reaction of acetals of aroylacetaldehydes with ketones and phenols.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1163–1165, September, 1972.  相似文献   

8.
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   

9.
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   

10.
Interest in the analysis of -hexachlorocyclohexane (-HCH) enantiomers as an alternative or complementary approach to elucidating isomer ratios of /-HCH has grown in recent years because it can provide useful information to evaluate the influence of different degradation and transformation processes. In this paper, a simple and rapid method for the determination of -HCH enantiomers in biota samples is described. The method developed consists of ultrasonic extraction, sulfuric acid silica gel cleanup, solid-phase extraction (SPE) column fractionation, and final determination with chiral high-resolution gas chromatography. Ultrasonic extraction greatly shortens the extraction process time, and the sulfuric acid silica gel and SPE cleanup perfectly remove lipids and other interference compounds in the lipid-rich samples. The method is found to be simple, less time-consuming, and easy to operate, thus providing a useful alternative method to assess the enantioselective breakdown of -HCH in biota system.  相似文献   

11.
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   

12.
The structures of the products of the polyformylation of Cu, Ni, and Co complexes of etioporphyrin (EP) as monoformyl-, ,-diformyl-, ,-diformyl-, and ,,-triformyl-EP were established by electronic, IR, and PMR spectroscopy and mass spectrometry. -Formyl--(N-methylformaldimine)-EP and porphyrins that contain a cyclopentane ring can be formed by alkaline treatment of the Vilsmeier formylation products.See [1] for communication 8.See [2] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 767–775, June, 1979.  相似文献   

13.
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   

14.
Conclusions The addition of thioacetic acid to the 5 bonds of 16- and 16-mercapto-3-hydroxypregn-5-en-20-one 3,16-diacetates (II) and (III) under radical conditions gives not only trans-diaxial addition products-6,16- and 6,16-dimercapto-3-hydroxy-5o;-pregnan-20-one 3,6,16-triacetates (IV) and (V) -but also cis-addition products-6,16- and 6,16-dimercapto-3-hydroxy-5-pregnan-20-one 3,6,16-triacetates (VI) and (VII).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 405–411, February, 1969.  相似文献   

15.
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   

16.
Alpha-counting with a commercial solid scintillator, LumaCap, in a liquid scintillation analyzer, has been studied. It has been found that LumaCap produces much more fluorescence than normal cocktail does, upon the reaction of -particles. Pulse height and pulse shape analysis have been applied for - and -discrimination successfully. This solid scintillator provides a useful means for -counting in normal liquid scintillation instruments.  相似文献   

17.
Conclusions The feasibility was demonstrated for the preparation of mono- and bis(,,-trihydro-perfluoroalkoxy) derivatives of sulfur hexafluoride by the fluorination of the corresponding sulfur tetrafluoride derivatives with elemental fluorine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1906–1908, August, 1988.  相似文献   

18.
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   

19.
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   

20.
    
cis- and trans-Cheilanthene-3, 19-diols — structurally close analogues of the parent of the cheilanthane sesterterpenoids cheilantha-6,13,19-triol and substances related to it — have been synthesized.Institute of Chemistry, Moldavian SSR Academy of Science, Kishinev. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 353–358, May–June, 1990.  相似文献   

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