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1.
The 2-(-methyl--nitrobutyl) derivatives of 2-imidazoline, benzimidazole, and benzoxazole and 2,4,6-tris-(-methyl--nitrobutyl)1,3,5-triazine have been synthesized. The nitroalkyl derivatives of 2-imidazoline and benzimidazole have been reduced to the corresponding 2-aminoalkyl derivatives.  相似文献   

2.
Tosylation of -cyclodextrin in an aqueous alkaline solution gave two regiospecific isomers (2-monotosyl--cyclodextrin(1) and 6-monotosyl--cyclodextrin(2)), that could recognize and catalyze small sized guest molecules; 2-monotosyl--CD recognized small sized guest molecules more effectively than did 6-monotosyl--CD.  相似文献   

3.
Neutrons from a source are moderated by means of hydrogenous materials such as polyethylene (PE) or water to reduce the energy of fast neutrons and to increase the fluence rate of moderated neutrons. The rise-time and -ray pulse height spectrum from a PE moderated241Am-Be neutron-gamma (n-) mixed source were measured by using6Li-BC501 scintillation detector and pulse shape discriminator (PSD) system. The difference in rise-time between and neutron signals tumed out to be 18.5 ns for the6Li-BC501 (n-) spectrometer system. The figure of merit (FOM) for this separation was estimated to be 1.52, and this was compared with the published results. From this comparison, the6Li-BC501 system has much superior characteristics in (n-) separation to other detector systems. Two Compton edges at around 1.87 and 3.99 MeV which are produced by H(n,)D reaction and by the first excited state of12C* from Be(, n)12C* reaction were also investigated.  相似文献   

4.
Summary Over platinized charcoal at 300° 1-(2-furyl)-3-alkanols, as a result of the hydrogenolysis of the furan ring, and 1-(tetrahydro-2-furyl)-3-alkanols, as a result of the isomerization of the tetrahydrofuran ring, give-diketones in yields of 35–50%.  相似文献   

5.
Fluorescent active host labeled at the upper and lower rims of -cyclodextrin, namely, mono-3A-deoxy-3A-pyrenebutylamido-6X,Y-O-bis-pyrenebutylate-mono-altro--cyclodextrin (-3) has been synthesized as a chemosensor for steroidal guests using fluorescence spectra change upon a guest addition. The -3 shows monomer and excimer fluorescence, which results in an increase of the intensity of monomer and decrease of excimer fluorescence with a host–guest binding in the cyclodextrin cavity. The extent of monomer and excimer fluorescence variations of -3 was used as an indication for the sensing ability for the guests examined. The guest-induced fluorescence changes were measured for 10–7 M solutions of -3. The sensing parameters (Iex/I0ex and Imon/I0mono) were used to describe the sensing ability of -3. The values of Iex/I0ex describe that -3 shows less selectivity for guests than that of mono-3A-deoxy-3A-pyrenebutylamido-6X-O-mono-pyrenebutylate-mono-altro--cyclodextrin (-2), and the values of Imon/I0mono show that -3 shows higher sensitivity and selectivity than that of -2.  相似文献   

6.
Summary 1. Paper chromatography has shown that the fruit ofC. dubium contains not less than eight substances of coumarinic nature; six of these (A, B, C, D, E, and H) have been isolated in the crystalline state.2. Substances B, D, and E are identical with isoimperatorin, imperatorin, and oxypeucedanin, respectively. Some properties of substance H have been determined. Prangenin [F] has been detected in the fruit ofC. dubium by paper chromatography.3. The structure of two new compounds has been established: substance A (cnidicin) (I) is 5, 8-di-(, -dimethylallyloxy) psoralen, and substance C (cnidilin) (II) is 5-(, -dimethylallyloxy)-8-methoxypsoralen.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 375–380, 1966  相似文献   

7.
Synthesis of γ-Polynitrocarboxylic Acids And Derivatives Thereof   总被引:1,自引:0,他引:1  
A synthesis of new branched -nitrocarboxylic acids and their derivatives (nitriles, amides, trinitroethyl esters) was developed proceeding from the corresponding aldehydes obtained by nitroform or 1,1-dinitroethane addition to 2-(2,2-dinitropropyl)acrylic aldehyde according to Michael reaction.  相似文献   

8.
The reactions of 1, 1, 3-trichloro-1-propene and also 1, 1, 1-trichloro-2-propene with acetoacetic ester gave -(, -dichlorallyl)acetoacetic ester (I). In the reactions with aniline and o- and p-toluidines, the corresponding -(, -dichloroallyl)--arylamino-crotonic esters were produced, thermal cyclization of which gave 2-methyl-3-(, -dichloroallyl)-4-hydroxyquinoline (II) and its 6CH3- (III) and 8CH3- (IV) homologs. With phosphorus oxychloride, II–IV gave the corresponding 4-chloro-substituted quinolines (V–VII); with concentrated sulfuric acid, II–VII were converted into the corresponding -quinolinylpropionic acids VIII–XIII.For part XI, see [5].  相似文献   

9.
The action of ammonia on - and -monomercurimethylenePyrylium perchlorates gave bis(pyridylmethylene)mercury derivatives, which undergo decomposition to the corresponding pyridine derivatives and mercuric chloride.See [1] for our preceding communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 887–888, July, 1981.  相似文献   

10.
The cis and trans isomers of 1-(3-halotetrahydro-2-furyl) derivatives of uracil, 5-substituted uracils, and cytosine were obtained by alkylation of 2,4-bis(trimethylsilyl) derivatives of uracil, 5-substituted uracils, and cytosine with 2,3-dihalotetrahydrofurans. 2,3-Anhydro compounds are also formed in the alkylation of 5-halouracil derivatives. The physicochemical properties of the compounds obtained and the antineoplastic activities of the 5-fluorouracil derivatives were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 94–99, January, 1987.  相似文献   

11.
Zusammenfassung dl-3,4-Dibenzyloxy--methyl-phenylalanin wurde aus 3,4-Dibenzyloxy-benzaldehyd nach Standardmethoden hergestellt. Sein N-Carboxy-Anhydrid wurde inDMSO mit den Natriumsalzen von p-Toluolsulfonamid und Methansulfonamid zu den N-Acyl-sulfonamiden umgesetzt, die durch katalytische Hydrierung in die vom Aldomet sich ableitenden N-Acyl-Sulfonamide übergeführt wurden.
dl-3.4-Dibenzyloxy--methyl-phenylalanine was prepared from 3.4-Dibenzyloxybenzaldehyde by standard methods. Reaction of its N-carboxy anhydride inDMSO with sodium p-toluenesulfonamide and sodium methanesulfonamide yielded the corresponding N-acyl sulfonamides, and subsequent catalytic hydrogenation the N-acyl sulfonamides derived from aldomet.
  相似文献   

12.
First experiments on the transmutation of long-lived129I and237Np using relativistic protons of 3.7 GeV are described. Relativistic protons generate in extended Pb-targets substancial neutron fluences. These neutrons get moderated in paraffin and are used for transmutation as follows:129I(n,)130I and237Np(n,)238Np. The isotopes130I (T 1/2-12.36 h) and238Np (T 1/2=2.117 d) were identified radiochemically. One can estimate the transmutation cross-section (n,) in the given neutron field as (129I(n,))=(10±2)b and (237Np(n,))=(140±30)b The experiments were carried out in November 1996 at the Synchrophasotron, LHE, Dubna, Russia. The investigation has been performed at the Laboratory of High Energies, JINR, Dubna.  相似文献   

13.
We have developed two synthesis routes for 4-amino derivatives of 6-nitro--carbolines: 1) consecutive conversion of 1,2-dimethyl-3-formyl-5-nitroindole to the 3-cyano derivative, condensation of the latter with DMF diethyl acetal, and cyclization of the enamine formed in this case with ammonia and benzylamine; 2) N-oxidation of 9-substituted 6-nitro--carbolines, transformation of N-oxides to the corresponding -carbolin-4-ones, from which the target compounds are obtained through the 4-chloro derivatives.For Communication 72, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 502–505, April, 1992.  相似文献   

14.
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   

15.
Solid combinations of naproxen with amorphous hydroxypropyl derivatives of -, -, and -cyclodextrin with an average substitution degree per anhydroglucose unit of 0.6 were investigated for thermal behaviour (differential scanning calorimetry), drug crystallinity (X-ray diffractometry), and dissolution rate (dispersed amount and rotating disc methods). Phase-solubility analysis and computer-aided molecular modelling were carried out to study the inclusion complexation of naproxen with hydroxypropyl cyclodextrins. The cavity size of the host is a selective factor for the solubilizing effect, complexing ability, and dissolution rate enhancement on naproxen, hydroxypropyl -cyclodextrin being markedly the most effective derivative. No relationship was found between the decrease in crystallinity of the drug dispersed in the amorphous carrier matrix and the geometrical features of the cyclodextrin macrocycle.  相似文献   

16.
A new approach for the determination of elemental uranium in uranium bearing ore, using high resolution -ray spectrometry, was applied. Using a variant of the enrichment technique an agreement of better than 1% has been obtained between -ray measurement results and a certified value obtained by other analytical methods. For the calibration of the -ray spectrometer uranium reference samples have been used which are made available jointly in Europe and the USA as Certified Reference Materials for Gamma-Ray Spectrometry (EC NRM 171 and NBS SRM 969, respectively). The measured ore has been put in a special designed container which ensured in all directions seen from the radiation window an uniform degree of infinite thickness of about 95%. The results can be taken as an example for the applicability of -ray spectrometry when high accuracy is required and under conditions were homogeneously distributed elemental uranium is embedded in larger amount of matrix material.  相似文献   

17.
METRIAREZ- and -, two new derivatives of 5-mercapto-1,2,4-triazole with - and -resorcylic acids have been synthesized and their physicochemical and chelating properties determined. With metal ions havingp andd electrons they form water-soluble coloured chelates at L M molar ratios of 1 1 with Cu2+ and Pb2+ ( and ), Hg2+ and Zn2+ () and Cd2+, In3+ and Bi3+ () and 2 1 with Fe3+, Fe2+, Co2+ and Ni2+ ( and ) and Zn2+ (). The chelates are non-extractable by organic solvents. The stability constants of these complexes, as well as their spectrophotometric sensitivity and extinction coefficients were determined. Iron and zinc in multivitamin tablets were determined spectrophotometrically using the ligands.  相似文献   

18.
The possibilities were evaluated of nondestructive determination of silicon content in large-scale samples of coal /about 20–50 kg/, based on the spectrometry of prompt -radiation from processes /n, n /, E=1779 keV and /n, /, E=3539 keV and 4935 keV. The neutron sources were either241Am–Be or252Cf located additionally in D2O moderator. A Ge/Li/ detector was used for -radiation detection. In exposure times of up to 2 h, the detection limits of 1.3% and 0.9% and accuracies of silicon determination of 0.66% and 0.40% have been achieved in case of /n, / and /n, n / processes, respectively.  相似文献   

19.
The reaction of the isomeric tetrachloro--, -, and -trifluoromethylpyridines and of 3,4,5-trichloro-2-trifluoromethylpyridine with sodium N,N-dimethyldithiocarbamate dihydrate has been studied. In the case of the -, and -isomers an intramolecular cyclization with the formation of 1,3-dithiol-2-one derivatives occurs and the remaining compounds give only products of mono- or disubstitution of chlorine atoms by a dithiocarbamate fragment at positions 4 or 6 of the pyridine ring. The structure of the compounds synthesized was proved using13C NMR and X-ray crystallographic analysis.See [6] for part 7.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, Chernogolovka 142432. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1278–1284, September, 1994. Original article submitted June 25, 1994.  相似文献   

20.
Approximately 5% of the -ray transitions in fission fragments are internally converted, giving rise to X-rays. X-ray energies are characteristic of Z, but yields depend strongly and not smoothly on Z and A of the fragments and on time. If these biases can be accepted, X-rays can be used to identify the atomic number of fission fragments. More generally, internal conversion and X-ray emission must be interpreted in the context of detailed knowledge of -ray transitions.  相似文献   

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