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1.
The reaction of the sodium salt of 2-mercapto-6-methyluracil with , -dibromoalkanes Br(CH2)Br (n=1,4,5,6) has given the corresponding , -bis(4-hydroxy-6-methyl-2-pyrimidinylthio) alkanes. The reaction of the same salt with 1,2-dibromoethane gave 7-methyl-5-oxo-2,3,4,5-tetrahydrothiazolo[3,2-a]pyrimidine and 5-methyl-7-oxo-2,3,4,7-tetrahydrothiazolo[3,2-a]pyrimidine, and its reaction with 1,3-dibromopropane led to 8-methyl-6-oxo-3,4,5,6-tetrahydro-2H-pyrimidino[2,1-b]-1,3-thiazine.  相似文献   

2.
A method was developed for obtaining previously unknown 1,3,7-tris(-haloalkyl)-, 1,7-bis(-chloroalkyl)-3-methyl-, and 1,3-bis(-chloropentyl)-7-methylxanthines.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya No. 9, pp. 2102–2105, September, 1989.  相似文献   

3.
1-Alkyl 3,5-bis(-hydroxyalkyl) isocyanurates were reacted with mercaptoacetic acid to obtain 3,5-bis(-mercaptoacetoxyalkyl) isocyanurates whose oxidation gives rise to macrocyclic disulfides.  相似文献   

4.
1,3-Dihydrobenzo[c]selenophene was synthesized from , -dibromo-o-xylene and sodium selenide.Translated from Khimiya Geterotsiklicheskikh Soedin-enii, No. 1, p. 24, January, 1972.  相似文献   

5.
Chemical transformations of 9,11-ethano-13,15-isoxazolinoprostanoids furnished new prostanoids with a bufunctional fragment of -hydroxyketone and -aminoalcohol in the -chain. The reaction of -hydroxyketones with methanesulfonyl chloride gave rise to prostanoids with an enone component in the -chain. 9,11-Ethano-16-thiaprostanoids were prepared for the first time by nucleophilic addition of thiols to the polarized double bond in the -chain. The 1,3-dipolar addition to terminal alkenes of nitrile oxides generated from nitromethylene derivatives of bicycloheptane provided 9,11-ethano-13,15-isoxazolinoprostanoids with an alkyl, phenyl, or additional heterocyclic fragment in the -chain.  相似文献   

6.
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   

7.
The reaction of ,-bis(1,3-thiazan-2-thion-4-on-3-yl)alkanes with hydrazine gives the corresponding ,-di(4-thiosemicarbazido)alkanes, which are readily acylated. Subsequent dehydration of the acylation products gives the corresponding 5,5-dialkyl-,-bis(2,3-dihydro-1,2,4-triazole-3-thion-4-yl)alkanes, which are converted to 5,5-dialkyl- , -bis (1,2,4-triazol4-yl)alkanes by known methods. The UV and ER spectral data are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1060–1062, August, 1977.  相似文献   

8.
The frequency response of a diffusion transducer with gauze electrodes, studied theoretically at high frequencies, is proportional to -3/2 starting with = D/R 2 at < /R 2 and to -1 at > /R 2. Here, = 2f, f is the signal frequency, the electrolyte viscosity, D a diffusion coefficient, and R the radius of the gauze filaments. The calculation is compared with experiment.  相似文献   

9.
Conclusions A method has been developed for the preparation of 1,3-bis(-haloalkyl)uracils with methylene chains of different lengths in the -haloalkyl radicals in the N1 and N3 positions of the pyrimidine ring.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1173–1177, May, 1986.  相似文献   

10.
1.  The corresponding 1,3-bis[-(p-toluenesulfonamido)alkyl]uracils are formed as a result of the reaction of 1, 3-bis(-bromoalkyl)uracils and the Na salt of p-toluenesulfamide.
2.  Interaction of l-(-bromobutyl)uracil with p-toluenesulfamide in a medium of n-butanol leads to formation of 9,18,19,20-tetraoxo-1,6,10,15-tetraazatricyclo[13.3.1.16.10]-eicosa-7, I6-diene,l-(-hydroxybutyl)-2-butoxypyrimid-4-one, and l-(-hydroxybutyl)-2-p-toluenesulfonamidopyrimid-4-one.
  相似文献   

11.
Summary A method for the preparation ofbis--appended hypericin derivatives bearingn-octyl,n-hexadecyl, and 2-(2-(2-hydroxyethoxy)-ethoxy)-ethoxymethyl substituents was developed. The key step — the synthesis of appropriately -substituted emodin derivatives — was achieved by solvolyzing 3-bromomethyl-1,6,8-triacetyloxy-anthracene-9,10-dione (-bromo triacetylemodin) in an appropriate alcohol in the presence of silver perchlorate. The correspondingbis--substituted hypericins were then prepared conventionally by dimerizing the -substituted emodin anthrones. The latter were prepared by reduction of the -appended emodins.
Zur Synthese von -substituierten Hypericinderivaten
Zusammenfassung Eine Methode zur Darstellung vonbis--substituierten Hypericinderivaten wurde entwickelt. Der Schlüsselschritt — die Synthese der entsprechenden Emodinderivate — wurde durch die Solvolyse von 3-Bromomethyl-1,6,8-triacetyloxyanthracen-9,10-dion (-Bromtriacetylemodin) im entsprechenden Alkohol in Gegenwart von Silberperchlorat ermöglicht. Die entsprechendenbis--substituierten Hypericinderivate wurden auf konventionelle Weise durch Dimerisierung der -substituierten Emodinanthrone dargestellt. Letztere erhielt man durch Reduktion der -substituierten Emodine.
  相似文献   

12.
By reactions of ,-diamines with 1,2-dihaloethanes there were synthesized ,-bis-N-aziridinoalkanes (la-g) and bis-N-aziridinoethyl ether (II). From 1,3-diaminopropane and dichloroethane bis-aziridine (III) was isolated in addition to (Ia). NMR spectra of the products were studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 882–885, April, 1991.  相似文献   

13.
1-Methyl and 1-benzyl 3,5-bis(-haloalkyl) isocyanurates were reacted with thiourea to obtain 1-methyl and 1-benzyl 3,5-bis[-[amino(imino)methylmercapto]alkyl] isocyanurates, respectively. Hydrolysis of the latter gave the corresponding 3,5-bis(-mercaproalkyl) izocyanurates.  相似文献   

14.
Conclusions A simple one-step method for the synthesis of 1,3-bis(-haloalkyl)uracils by reacting the Na salts of uracil and its derivatives with ,-dihaloalkanes has been developed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 880–884, April, 1977.  相似文献   

15.
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   

16.
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   

17.
Measurements of the partial molar volumes in water at 25°C of the mono-and dihydrochlorides of the ,-diaminoalkanes, up to a chain length of 10 carbon atoms, are reported. Volumes of ionization have been determined and the electrostriction of the solvent calculated. Effects of the substituents are felt up to the -carbon atom, but thereafter are only very weak or nonexistent.  相似文献   

18.
Summary We have described the synthesis of macrocyclic diacetylene ketones by oxidative condensation of aliphatic ,-diacetyiene ketones.  相似文献   

19.
Conclusions We have examined the condensation of 1,1,3-trimethoxy-3-dimethylaminopropane with cyclic and heterocyclic ketones and with enaminoketones; we have synthesized a series of unsaturated-dimethylamino and,-bis(dimethylamino) ketones, which the PMR spectra indicate as having the trans configuration of the methine protons and to exist as the S-trans conformers about the, -bond.Translated from Izvestiya Akademii Nauk SSSR, No. 1, pp. 116–122, January, 1978.  相似文献   

20.
Summary Silica has been modified by an esterification reaction using either n-alcohols or - diols. The grafting ratios were evaluated by elemental analysis of carbon or by the weight loss of the grafted silica heated to 700°C. The grafting ratio can be easily fixed by changing the silica to reactant impregnation ratios. In the case of n-alcohols, the grafting ratios do not vary monotonously with the number of carbon atoms of the grafts and the density of the grafted layer is 25% higher for - diols than for n-alcohols. This observation needs further investigation.  相似文献   

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