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1.
    
Conclusions A culture ofActinomyces roseochromogenus ATCC 3347 and the corresponding cell-free preparation reduce 17-oxygen-containing 20-oxopregnanes to the 20-alcohol. A culture ofA. roseochromogenus ATCC 3347 is capable of reducing 4-3-oxo- to 3-hydroxy-5-steroids, as has been shown by fermentation with 16, 17-epoxyprogesterone as an example. It has been shown that certain substituents in the steroid molecule affect the course of the 20-reduction by a culture ofA. roseochromogenus ATCC 3347.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 3, pp. 149–156, 1969  相似文献   

2.
To improve the activity and the cell specificity of gene transferof polyamidoamine starburst dendrimer, we prepared -CyD conjugates with mannosylateddendrimers (generation 2 (G2), man--CDE conjugates) having various degrees of substitution(DS) of mannose residue. The man--CDE conjugates (DS 1, 3 and 5) formed complexeswith plasmid DNA (pDNA), but man--CDE conjugate (DS 8) did not. The gene transferactivity of man--CDE conjugates (DS 1, 3 and 5) and -CDE conjugate was augmented with an increasein the charge ratio of vector/pDNA, without showing cytotoxicity. Man--CDE conjugates(DS 3 and 5) showed higher gene transfer activity than -CDE conjugate in A549 cells, whichrecognize mannose, but man--CDE conjugates (DS 1 and 8) showed almost comparable gene transfer activityto -CDE conjugate (G2). On the other hand, no appreciable enhancing effect of man--CDEconjugates (DS 3 and 5) on the transfer activity was observed in NIH3T3 cells, which do not recognizemannose. These findings suggest that man--CDE conjugates (DS 3 and 5) can be new preferablecell-specific non-viral vectors of pDNA to cells which recognize the mannose moiety.  相似文献   

3.
The corresponding ,-di(3-phenoxazinyl)-p-phenylenedimalononitriles and p-phenylenedimalononitrile are formed in the reaction of tetracyanoquinodimethane with phenoxazine and its heterocyclic analogs. The reaction scheme is discussed.Communication 7 from the series The chemistry of quinomethanes. See [1] for Communication 6.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 317–320, March, 1981.  相似文献   

4.
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   

5.
From the far-eastern starfishHenricia sp. we have isolated and characterized the new polyhydroxysteroid (24S)-5-cholestane-3,4,6,8,15,24-hexaol and three new glycosides: (24S)-5-cholestane-3,4,6,8,15,24-hexaol 3-O-(2,4-di-O-methyl--D-xylopyranoside) (henricioside H1), 24-methyl-5-cholesta-4,22E-diene-3,6,8,15,16,26-hexaol 3-O-(2,3-di-O-methyl--D-xylopyranoside) (henricioside H2), and the 22,23-dihydro derivative of henricioside H2 (henricioside H3).Pacific Ocean Institute of Bioorganic Chemistry, Far-Eastern Scientific Center, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 249–253, March–April, 1993.  相似文献   

6.
Zusammenfassung Aus den entsprechenden -Bromestern werden durch Umsetzung mit Natriumnitrit die -Oximinodicarbonsäuredimethylester C7 und C9 und der , -Dioximinoazelainsäuredimethylester erhalten. -Methyladipinsäure wird zum Gemisch aus -Bromund -Bromester umgesetzt. Mit Natriumnitrit wird -Nitro-und -Oximino--methyladipinsäuredimethylester erhalten.
The -oximino dicarboxylic dimethyl esters of C7 and C9 and the , -dioximino azelaic acid dimethyl ester are received from the corresponding -bromo esters by reaction with sodium nitrite. -Methyladipic acid is reacted with bromine to a mixture of the -bromo and -bromo ester. Reaction with sodium nitrite gives the -nitro ester and the -oximino ester of -methyl adipic acid.


5. Mitt.:H. Reinheckel, Mh. Chem.98, 1217 (1967).  相似文献   

7.
248Cm and249Bk metals were prepared by thermal reduction of their oxides with thorium and metallic249Cf with metallic lanthanum. These rare actinide samples of 1.0 mg in mass were thin layers on a flat substrate and were investigated by X-ray technique. Dhcp lattice parameters of -Cm, -Bk and -Cf as main phases in X-ray diagrams are presented. The effect of impurities on the -Cm lattice parameters is shown. Fcc lattices for the high temperature form of Cm metal (-Cm) with a=0.4933 nm, and of Cm and Bk monoxides (a=0.502–0.504 nm and a=0.5002 nm, respectively) have been observed. Thermal expansion coefficients for -Cm and -Bk at 80–300 K were calculated. Identification problems of fcc lattices and oxidation features of metals prepared are discussed.  相似文献   

8.
summary The reaction of telomerization of ethylene with carbon tetrachloride or chloroform is initiated by hexacarbonyls of chromium, molybdenum, and tungsten at 115–120, forming ,,,-tetrachloroalkanes and ,,-trichloroalkanes. respectively.  相似文献   

9.
A new method was developed for the synthesis of -alkyl- and ,-dialkyl--phenyltryptamines based on alkylation of nitroalkanes with -phenyl-nor-gramine.  相似文献   

10.
From the stems of Crimean ivyHedera taurica Carr. (fam. Araliaceae) we have isolated previously known glycosides of oleanolic acid — the 3-O-[O--L-rhamnopyranosyl-(12)--L-arabinopyranoside], the 3-O--D-glucopyranuronoside, and the 3-O-[O--D-galactopyranosyl-(12)--D-glucopyranuronoside]; known glycosides of hederagenin — the 3-O--L-arabinopyranoside, the 3--D-glucopyranoside, the 3-O-[O--D-glucopyranosyl-(12)-O--L-arabinopyranoside], and the 3-O--D-glucopyranuronoside; and also the new triterpene glycoside St-D2, hederagenin 3-O-[O--L-rhamnopyranosyl-(12)--D-glucopyranoside].Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 411–416, May–June, 1997.  相似文献   

11.
INAA of Minoan ceramics from Kommos,Crete   总被引:1,自引:0,他引:1  
A recent study concerning the deviation of the E–(1+) epithermal neutron flux distribution from the E–1 law, developed by F. DE CORTE et al. is applied to -determination in different channels of the CRN reactor (Strasbourg). It is found that the coefficient is positive inside the reactor core and negative outside. The accuracy of the neutron activation analysis using the corrected resonance integral I() is tested.  相似文献   

12.
ESR and XPS investigations on Cu/–Al2O3 catalysts with various amounts of Cu loading are reported. Experimental data are related to the surface structure and dispersed state of catalysts. The results show that ESR can be used as a means of charaterizing monolayer dispersed state for paramagnetic supported catalysts.
Cu/–Al2O3 . . .
  相似文献   

13.
Conclusions The reaction of diphenylchlorophosphine with ,,-trichloro--hydroxyethyl ethyl sulfide in the presence of triethylamine leads to the formation of -ethylthio-,,-trichloroethyl diphenylphosphonite. The reaction of diphenylchlorophosphine with dimethyl -hydroxy--propylthiophosphonate in the presence of triethylamine gives -propylthio--dimethylphosphonoethyl diphenylphosphonite. The phosphorylated hemimercaptals obtained are thermally unstable and decompose to S-alkyl diphenylthiophosphonites and the corresponding carbonyl compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2619–2621, November, 1985.  相似文献   

14.
Conclusions The cyclic sulfites of the 3, 4- and 3,4-caranediols were synthesized as mixtures of two isomers that differ in the relative position of the S=O and 10-CH3 groups.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1670–1671, July, 1976.  相似文献   

15.
In terms of a unitary approach, the ability of complexes, clusters and metals of transition and nontransition elements for covalent interaction with reagents has been analyzed. the requirements for the catalysts to be efficient in the covalent activation of substrates have been formulated.
, . .
  相似文献   

16.
Summary A semi-preparative low-pressure liquid-chromatographic procedure using tribenzoylcellulose has been developed for the separation and isolation of the four -bisabolol stereoisomers. Stereochemical assignments were made by HPLC-polarimeter coupling and by using the authentical isomers. This method can be applied to the quality control of chamomile preparations, as it allows the detection of adulterations resulting from admixtures of synthetic -bisabolol. In addition, the isolation of all four -bisabolol stereoisomers from commercially available synthetic -bisabolol has been made possible.  相似文献   

17.
Catalytic preparation of diacetone alcohol from acetone was studied using strong basic ion exchangers as catalysts. A continuous process was carried out in an enlarged laboratory set-up with controlled flow rate. Experiments were performed with respect to experiment duration, temperature, flow rate, catalyst porosity and catalyst-acetone ratio. The quantity of DAA was determined by gas chromatography. The effects of temperature, catalyst porosity and catalyst-acetone ratio on the reaction course were significant in comparison with other parameters examined. An exponential dependence of C/A ratio on DAA yield was found.
() , . . , , , /. . , / (/) . - /.
  相似文献   

18.
Trimethoxybenzenes were oxidized to dimethoxy-p-benzoquinones in fairly good yields (50–60%) with hydrogen peroxide in the presence of heteropolyacid in the solvent of acetic or formic acid.
-- (50–60%) , , .
  相似文献   

19.
Ethyl -ethoxymethyleneacetoacetate and -ethoxymethylenebenzoylacetate react with benzylidenehydrazine andp-bromobenzoylhydrazine to give hydrazones of the corresponding ethyl -formylacylacetates. It was established by1H NMR and IR spectroscopy that hydrazones, which were obtained from benzylidenehydrazine, andp-bromobenzoylhydrazone of ethyl -formylacetoacetate exist in the ketoenamine (ketoenhydrazine) form, whereasp-bromobenzoylhydrazone of ethyl -formylbenzoylacetate exists in the enolimine (enolhydrazone) form.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2293–2296, September, 1996.  相似文献   

20.
- and -Cyclodextrin (CD) and heptakis-2,6-di-O-methyl--cyclodextrin (DIMEB) form soluble inclusion compounds with mefenorex (MEF); with -CD a partial inclusion occurs. No solid inclusion compound could be obtained with the four CDs. -, -CD and DIMEB, but not -CD, enhance the nitrosation rate of MEF if the nitrosation assay procedure (NAP test) is applied. During this reaction with - and -CD, solid inclusion compounds of the CDs and nitrosomefenorex (NMEF) precipitate.Part of the Ph.D. thesis of V. Wedelich, Freie Universität Berlin, 1985.  相似文献   

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