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1.
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   

2.
2-Acylmethyl-1,3-oxathiolanes, which form oximes with hydroxylamine and perchlorates with perchloric acid, were synthesized by reaction of -alkynyl ketones with ß-mercaptoethanol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1041–1043, August, 1978.  相似文献   

3.
The products of condensation of 1,3-hydroxylamino oximes with formaldehyde have 1-hydroxy-1,2,5,6-tetrahydropyrimidine 3-oxide (cyclic form) structures, the products of condensation with acetone have N-(3-oximino-substituted)-,-dimethylnitrone (open form) structures, and the products of condensation with acetaldehyde exist in solution in the form of a tautomeric mixture of the open and cyclic forms. The products of condensation of alkyl-aromatic 1,3-hydroxylamino oximes with acetaldehyde have N-(3-oximino-substituted)--nitrone (open form) structures.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 252–258, February, 1977.  相似文献   

4.
2-(-Oximinoethyl)-2-methylthiirane was obtained by the reaction of 3,4-dibromo-3-methyl-2-butanone oxime with sodium sulfide. At the same time, the O-carbamoyl derivative of the ,-dibromo oxime was converted to the corresponding substituted ,-unsaturated oxime under the same conditions. Thiirane oxime, like its O-carbamoyl derivative, underwent the desulfuration that is characteristic for thirranes under the influence of tributylphosphine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 751–753, June, 1982.  相似文献   

5.
The direction taken by the reaction of -hydroxylaminooximes (prepared by the action of hydroxylamine on -halogenoketones) with aldehydes depends on the geometric configuration of the oxime group, cis isomers reacting with benzaldehyde to give N -substituted -phenylnitrones and with acetaldehyde to give derivatives of 4H-1, 2, 5-oxadiazine. Anti--hydroxylaminooxime and acetaldehyde give substituted 1 -hydroxy-3-imidazolin-3-oxide. The structures of the compounds synthesized check by analyses of their UV and IR spectra.For Part VI see [1].  相似文献   

6.
6(E)- and 6(Z)-(3-Ethoxycarbonylpropyl)- and -(3-carboxypropyl)oximes of 16,17-cyclohexanopregn-4-ene-3,6,20-trione were synthesized. The reactions of these ester ligands with pentarane-binding proteins of the uterine cytosol and blood serum were studied; the latter exhibits a higher affinity. The preferred binding of the oxime (E)-isomer relative to the (Z)-isomer was noted.  相似文献   

7.
The configurational (kinetic) stability of the anionic and zwitterionic forms of 1-methylpyrazolecarbaldehyde oximes and 1-methylimidazolecarbaldehyde oximes and their quaternary ammonium derivatives in aqueous solutions has been established. In an acid medium, isomerization takes place and an E-Z equilibrium of the cations of the oximes is established. The changes in the relative thermodynamic stabilities of the stereoisomers of the heteroaromatic carbaldehyde oximes as functions of the size and nature of the ring, the position of the oxime group, and the steric loading are due to spatial factors and electrostatic interactions. To substantiate the preferred conformations of the Z aldehyde oximes the differences in the values of the chemical shifts of the protons of the ring and the rates of their deuterium exchange have been used.For Communication II, see [1],Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1176–1180, September, 1973.  相似文献   

8.
The reaction of 5-acetylindole with hydroxylamine with subsequent reduction of the resulting oxime gave -(5-indolyl)ethylamine. Coupling of 4-(2-phthalimidoethoxy)- and 4-(2-phthalimidoethylthio)phenyldiazonium chlorides with ethyl -acetyl--phthalimidovalerate, subsequent cyclization of the resulting hydrazones, hydrolysis, decarboxylation, and removal of the phthalyl protecting group led to the formation of 5-(2-aminoethoxy)- and 5-(2-aminoethylthio)tryptamines, respectively.For Communication 137, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 46–48, January, 1992.  相似文献   

9.
We have the reaction of -acyl--aminovinyl of the 8-azasteroid series with ethanedithiol. The occurrence and orientation of the reaction are determined by structural and steric factors. As applied to derivatives of 8-azasteroids of the D-homo series, the reaction is irreversible and consequently the dithioacetal derivatives of this series are easily hydrolysed under acid and base conditions. Desulfurization over Raney nickel of the 17-dithioacetal derivative of 8-azagona-12,17-dione occirs with simultaneous dehydrogenation of the C ring and leads to the 17-deoxo-9,11-dehydro, ehile desulfurization of the 1-dithioacetal of 8-aza-D-homogona-12,17-a-dione leads to the 12-deoxo derivative. By reaction of the 12-dithioacetal of 8-aza-D-homogona-17a-one with hydroxylamine, we obtained the 12-oximino derivative, which is the result of an unusual reaction at the site of the spiro coupling of the dithiolane ring with the 8-azasteroid ring.Institute of Bioorganic Chemistry, Academy of Sciences of Belarus, Minsk, 220141. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 187–194, February, 1995. Original article submitted December 15, 1994.  相似文献   

10.
It is shown that it is possible to carry out free radical cyanoethylation of tetrahydrofuran, to give the nitrile of -tetrahydrofuranpropionic acid in 50–60% yield.  相似文献   

11.
    
Summary 1. The carbodiimide method has been used for the first time for the synthesis of aminoacyl derivatives of glucose with aspartic acid.2. A new method of synthesizing 6-O-(N-CBA--L-aspartyl) derivatives of sugars at a primary hydroxyl group by condensing N-carbobenzoxy-L-aspartic anhydride with the unprotected monosaccharide in pyridine has been developed.3. The stability of 6-O-(N-carbobenzoxy--L-aspartyl)-D-glucose and 6-O-(-L-aspartyl)-D-glucose to hydrolysis at various pH's and to hydroxylaminolysis at pH 8 has been studied.Khimiya Prirodnykh Soedinenii, Vol. 1, No. 2, pp. 77–82, 1965  相似文献   

12.
The N-bonded nitrile complexes -[Co(tetren)NCR]3+ (R=Me, Ph, p-MeOC6 H4) have been prepared by the reaction of -[Co(tetren)OH2]3+ with the corresponding nitrile. The kinetics of base hydrolysis have been studied by pH-stat methods. The reactions involve an SN1CB displacement of the nitrile to give the hydroxopentamine; nucleophilic attack at the nitrile carbon to give the corresponding carboxamido complex does not occur. NaN3 reacts with the nitrile complexes in slightly acidic solution (pH ca. 5.7) to give the tetrazolato complexes [Co(tetren)N4 R]2+ (R=Me, Ph) which have been characterised. The reaction of azide ion with -[Co(tetren)NCMe]3+ has been studied kinetically. The reaction is biphasic involving the initial rapid formation of the N1-bonded (5-methyltetrazolato) pentaminecobalt(III) complex with k=2×10–2dm3 mol–1s–1 at 25°C followed by the slow isomerisation to the N2-bonded complex with k=3.5×10–5s–1 at pH 5.7.  相似文献   

13.
The -methylketoside of N-acetylneuraminic acid methylester (4) is transformed via the deacetylated compound5 into the 9,8-O-isopropylidenderivative6 which could be oxidized regioselectively by RuO4 to the corresponding 4-oxo-sialic acid analogue7. Reduction with the boraneammonia complex produces a 1:1 mixture of6 and the desired -methylketoside of 9,8-O-isopropyliden-4-epi-N-acetyl-neuraminic acid methylester (8). Removing of the isopropylidene group gives the -methylketoside of 4-epi-N-acetylneuraminic acid methylester (9), which was further transformed to the ammonium salt of 4-epi-N-acetylneuraminic acid -methylketoside (10). On the other hand compound5 was turned into the 4,8,9-tri-O-t-butyldimethylsilylderivative11 a from which the corresponding 7-oxo-compound12 by oxidation with RuO4 derives. The reduction of12 with BH3 - NH3 yielded a 1:1 mixture of the starting material11 a and the desired 7-epi-derivative13 a which gives either via the purified peracetylated -methylketosid of 7-epi-N-acetylneuraminic acid methylester (14) or a direct saponification the sodium salt of 7-epi-N-acetylneuraminic acid--methylketoside (15).Applying the Königs-Knorr procedure to the peracetylated 8-epi-N-acetylneuraminic acid methylester (16) gives rise to the formation of a 1:1 mixture of the corresponding - and -methylketosides17 and18 besides traces of the corresponding 2,3-dideoxy-2,3-dideohydro-sialic acid derivative19. After chromatographic separation of17 further saponification leads to the sodium salt of 8-epi-N-acetylneuraminic acid--methylketoside (20). In an analogous procedure the sodium salt of 7,8-di-epi-N-acetylneuraminic acid--methylketoside (25) was prepared starting from the peracetylated 7,8-di-epi-N-acetylneuraminic acid methylester (21), whereby a mixture of the - and -methylketosides22 and23 was formed in a ratio 95:5 besides traces of the peracetylated 2,3-dideoxy-2,3-didehydrosialic acid methylester (24).
On study leave from the Department of Chemistry, Postgraduate and Research Center, R.B.N.B. College, Shrirampur-413709 (MS), India  相似文献   

14.
    
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   

15.
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   

16.
Vinyl-furancarboxylate has been synthesized by the reaction of-furancarboxylic acid with acetylene and with vinyl acetate in the presence of various catalysts. The structure of the vinyl ester has been confirmed by IR spectra and by catalytic hydrogenation. The acid and alkaline hydrolyses of vinyl-furancarboxylate have been studied.  相似文献   

17.
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   

18.
1-(-Alkoxyethyl)- and 1-(-phenoxyethyl)benzimidazole-2-thiones were obtained in the reaction of 1-vinylbenzimidazole-2-thione with alcohols and phenol in the presence of gaseous hydrogen chloride. It was established that partial hydrolysis of the 1-(-alkoxyethyl)benzimidazole-2-thiones to benzimidazole-2-thione with subsequent alkylation with excess alcohol at the exocyclic sulfur atom occurs under the conditions of the investigated reaction. A convenient method for the alkylation of thiones was proposed, and a number of 2-alkylthiobenzimidazoles were synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 805–807, June, 1984.  相似文献   

19.
We have studied the reaction of nitrile oxides with nitrogen tetroxide. It was shown that the reaction is selective: acetonitrile oxide yields ethylnitrolic acid, -oximinophenylacetonitrile oxide gives a mixture of isomers of phenylnitrofuroxan, and aromatic nitrile oxides give aryltrinitromethanes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1620–1622, July, 1990.  相似文献   

20.
Summary Oximes of chiral ketones can be separated into enantiomers by capillary gas chromatography on the chiral polysiloxanes XE-60-L-valine-(S)- or (R)--phenylethylamide. Usually predominantly E-isomers are formed and are better separated than Z-isomers. From time-dependent gas chromatographic measurements it can be concluded that the oximes are configurationally stable and that racemization during oxime formation is negligible. The order of elution of enantiomers depends on the structure of the ketone and is different for aliphatic and alicyclic compounds.  相似文献   

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