Synthesis of two regiospecific isomers of monotosyl-γ-cyclodextrin

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.     

Gamma-ray pulse height spectrum of241Am-Be source by ‘Li-BC501 (n-γ) spectrometer system

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.     

New method for the synthesis of γ-diketones

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%.     

Synthesis of 1-(3-halotetrahydro-2-furyl) derivatives of uracil, 5-substituted uracils,and cytosine

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.     

Fluorescent Molecular Sensing System Based on Tri-Pyrenes-Labeled γ-Cyclodextrin at the Hetero Rim

Fluorescent active host labeled at the upper and lower rims of -cyclodextrin, namely, mono-3^A-deoxy-3^A-pyrenebutylamido-6^X,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 (I_ex/I⁰_ex and I_mon/I⁰_mono) were used to describe the sensing ability of -3. The values of I_ex/I⁰_ex describe that -3 shows less selectivity for guests than that of mono-3^A-deoxy-3^A-pyrenebutylamido-6^X-O-mono-pyrenebutylate-mono-altro--cyclodextrin (-2), and the values of I_mon/I⁰_mono show that -3 shows higher sensitivity and selectivity than that of -2.     

Synthesis of γ-Polynitrocarboxylic Acids And Derivatives Thereof

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.     

Furocoumarins ofCnidium dubium

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     

Nitroalkyl derivatives of some heterocyclic compounds

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.     

Synthesis and properties of bis(pyridylmethylene)mercury derivatives

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.     

First experiments on transmutation studies of129I and237Np using relativistic protons of 3.7 GeV

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.     

Acetals of lactams and acid amides. 73. Synthesis and some properties of derivatives of 6-nitro-γ-carboline

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.     

Porphyrins. 9. New data on the polyformylation of metal complexes of etioporphyrin I

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.     

Interaction of naproxen with α-, β-, and γ-hydroxypropyl cyclodextrins in solution and in the solid state

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.     

High precision determination of uranium in ore by gamma-ray spectrometry

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.     

2-Amino-4-[2-(5-nitro-furyl)vinyl]thiazole and its derivatives

The reactions of 4-bromo-1-(5-nitro-2-furyl)but-1-en-3-one and its 2-methyl and 2-chloro derivatives with thiourea and its N-allyl and N-phenyl derivatives have yielded 2-amino-4-[-5-nitro-2-furyl)-vinyl]thiazole and its - and N-substituted derivatives. 2-Amino-4-[-(5-nitro-2-furyl)vinyl]thiazole and its -methyl derivative have also been prepared by the direct reaction of the corresponding , -unsaturated ketones with bromine and an excess of thiourea in chloroform, as was shown by a comparison of UV spectra. A series of N-acyl derivatives of the aminothiazoles has been obtained. UV and IR spectra are given.     

Reactions of polyhalopyridines. 8. Reactions of polychlorotrifluoromethyl-pyridines with sodium N,N-dimethyldithiocarbamate. Structure of the 8-trifluoromethylbis-1,3-dithiolo-[4,5-b:4′,5′-e]-pyridine-2,6-dione molecule

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.     

The emission of X-rays by fission fragments

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.     

Synthesis and transformations of 2-(2-furyl)- and 2-[β-(2-furyl)vinyl] phenanthr [9,10]imidazoles

The corresponding 2-(2-furyl)- and 2-[-(2-furyl)vinyl] phenanthr[9,10]imidazoles were obtained by the condensation of 9,10 phenanthrenequinone with furfural, -(2-furyl)acrolein, and their 5-bromo and 5-nitro derivatives in the presence of ammonium acetate in glacial acetic acid. Their metallation, acetylation, nitration, and replacement of halogen by a nitro group were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1014–1016, August, 1971.     

Inclusion complexes ofγ-cyclodextrin with coronene in aqueous methanol

Coronene has been found to form an inclusion complex with -cyclodextrin (-CD) in methanol-H₂O (6:4 v/v). The inclusion complex, which has a 2 : 1 stoichiometry of -CD to coronene, tends to bind methanol. Upon addition of 1-adamantanol or adamantane to a solution of -CD and coronene, the absorption spectrum of coronene underwent changes in a manner similar to that observed when the -CD concentration was increased in a coronene solution, indicating the formation of a ternary complex composed of -CD, coronene, and 1-adamantanol or adamantane. The complex-forming equilibrium was investigated on the basis of fluorescence measurements.     

Synthesis and Structural Features of 1-Acyl-1-nitro-2-furyl(thienyl)ethenes

A one-stage synthesis of 1-acyl-1-nitro-2-furyl(thienyl)ethenes was developed and structural assessment of the products was performed by means of ¹H, IR, and UV spectroscopy and dipole moment measurements. The acetyl derivatives have Z configuration, and the benzoyl derivatives, E configuration. The UV and IR spectra, as well as the rather high dipole moments ( 5-6 D) point to an essential contribution in the structures of dipolar forms.