Extraction of Polonium from Aqueous α-Hydroxyisobutyric Acid Solutions Using Dioctyl Sulphide, Cyanex 272, Cyanex 301 or Cyanex 302 in Toluene

A study of the extraction of polonium from aqueous solutions containing -hydroxyisobutyric acid (-HIBA) was performed with four different extractants, di-n-octyl sulphide (DOS), Cyanex 272, Cyanex 301 and Cyanex 302, dissolved in toluene. The extracted complex for DOS at low -HIBA concentrations is most likely PoO(-HIB)₂·2DOS, while at higher -HIBA concentrations there seems to be a solvating effect implicating an extracted complex of the type PoO(-HIB)₂(-HIBA)₂·2DOS. For the extraction of polonium with Cyanex 272 the results are inconclusive. The extracted complex is either PoOA₂ or PoO(-HIB)₂·2HA. For extraction with Cyanex 301 or Cyanex 302 the major extracted species does not contain any -HIBA molecules. The neutral species in both cases is PoOA₂, extracted at low extractant concentrations, while at higher extractant concentrations a complex of the type PoOA₂·xHA is extracted. The extraction of polonium increases in the order Cyanex 272 < DOS < Cyanex 302 < Cyanex 301.     

Conformational study of some α-aminoketones

Conclusions In -N-morpholylacetone, -N-piperidylacetone, -N-dimethylaminocyclohexanone, -N-piperidylcyclohexanone and -N-morpholylcyclohexanone in hexane and in benzene the conformational equilibrium about the C-C bond predominantly favors the uneclipsed conformers. For amino derivatives of acetone in chloroform the eclipsed conformer predominates, while for aminocyclohexanones the solvent has no effect on the position of equilibrium. The gauche conformer with respect to the C-N bond predominates in all cases.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 839–843, April, 1989.     

Excess enthalpies of aqueous solutions of small peptides at 25°C

Heats of dilution of aqueous solutions of the following di-and tripeptides were determined at 25°C over a wide concentration range: -alanyl-glycine, -alanyl--alanine, DL--alanyl-glycine, glycyl-DL--alanine, L--alanyl-L-alanine, DL--alanyl-DL--alanine, DL--alanyl-DL-valine, DL--alanyl--alanine, glycyl--aminobutyric acid, glycyl-L-leucine and DL--alanyl-glycylglycine. The excess enthalpies H^ex and partial molar relative enthalpies L₂ were calculated and enthalpy coefficients of intermolecular interaction were analysed using the additivity principle of Savage and Wood. The concentration dependence of the enthalpic characteristics of peptide-peptide interactions is discussed based on of their hydrophobicity and hydrophilicity. The three-stage model of peptide association is described using enthalpic coefficients of intermolecular interactions.     

α-hydroaxyalkyl(benzyl)furozans and α-hydroxyalkyl(benzyl)furoxans synthesis and reactivity

A general and simple preparative method for the synthesis of -hydroxyalky(benzyl)furazan and -furoxan derivatives is proposed, The method involves reduction of acyl or ethoxycarbonyl substituents in these heterocyclic compounds with NaBH₄ in ethanol. Based on the alcohols thus prepared, a number of previously unknown functional derivatives (-nitroxyalkyl--haloalkyl-, and -azidoalkylfurazans and -furoxans) have been synthesized.Translated fromInvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7. pp, 1782–1788, July, 1996.     

Study of the rotational isomerism about the C-O bond in six-membered secondary-tertiary diols

We have determined the spectroscopic characteristics, the dipole moments, and the Kerr constants of the stereoisomers of the secondary-tertiary diols of the cyclohexane and bicyclo [4.1.0]pentane series: 3,4-dihydroxy-3-carane (I), 3,4-dihydroxy-3-methylnorcarane (II), 3,4-dihydroxy-3-methylnorcarane (III), 4, 5-dihydroxy-3-methylcyclohexene (IV), 3,4-dihydroxy-3-carane (V), 3,4-dihydroxy-3-methylnorcarane (VI), 3, 4-dihydroxy-3-carane (VII), and 3,4-dihydroxy-4-methyl-3-carane (VIII). It was found that the cis diols are more polar than their trans isomers. It was shown by electrical and electrooptical methods that rotamers with a gauche orientation with respect to the tertiary C-O are stable relative to those containing the diol at the ordinary C-C bond of the ring.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 619–625, March, 1991.     

Local-density-functional approximation for exchange-correlation potential

Local exchange-correlation potential has been derived starting from the free electron gas model.Ab initio way of calculating the parameter of the X method is presented. Self-consistent and statistical exchange-correlation parameters have been determined. The self-consistent parameters have been used to calculate the electron binding energies of Neon, Argon and Krypton. We suggest using statistical exchange-correlation parameter in molecular calculations. The statistical exchange-correlation parameter has been applied to study the electron binding energies of the molecules H₂O and HF. It is shown that the electron binding energies calculated with the self-consistent and the statistical parameters show agreement with the experimental values.Dedicated to Professor J. Koutecký on the occasion of his 65th birthday     

Telomerization of ethylene and carbon tetrachloride or chloroform in the presence of the hexacarbonyls of chromium,molybdenum, and tungsten

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.     

Reaction of steroido[16α,17α-d]-4′h-1′,2′-oxazoles with methyl fluosulfonate

Conclusions The methylation of steroido[16,17-d]-4H-1,2'-oxazoles with methyl fluosulfonate leads to N-methyl-3-hydroxysteroido[16,17-d]tetrahydro-1,2-oxazoles, which when treated with POC1₃ are converted to steroidal 16-(2-glyoxyl)17-lactones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1924–1926, August, 1977.     

Infrared Spectroscopy Analysis of Oxyhydroxides as Intermediate Species in the Formation of Iron Oxides-Silica Xerogels

A detailed infrared spectroscopy analysis in the 2500 to 3800 cm^–1 region has been used to study the formation of species in samples of iron oxides embedded in silica xerogel matrix. We report the presence of , , and forms of iron oxyhydroxides as intermediate species in the formation of -Fe₂O₃, -Fe₂O₃ and -Fe₂O₃ starting from three different iron precursors: iron nitrate, iron chloride and nanometric Fe particles prepared by chemical reduction. Our results show that under thermal dehydration and forms of iron oxyhydroxides transform into hematite and maghemite, respectively, whereas the form transform to the -Fe₂O₃ without going through an intermediate iron oxide phase.     

Fatty acids and prostaglandins of thermal cyanobacteria

The compositions of the fatty acids and prostaglandins of extracts from thermophilic cyanobacteria of the taxaOscillatoria andMicrocystidaceae have been investigated. The fatty acids include not only saturated but also polyunsaturated species, including 20:3, 20:4, and 22:4 acids with a known pharmaceutical effect. It has been shown for the first time that the lipid fraction of thermophilic cyanobacteria includes a set of prostaglandins of groups A, E, and F, both in the free form and in the form of esters — MeA₁, AcA₁, AcMeA₁, MeA₂, AcA₂, AcMeA₂, MeA₃, AcA₃, AcMeA₃, 6-ketoE₁, MeE₁, AcE₁, AcMeE₁, MeE₂, AcE₂, AcMeE₂, MeE₃, AcE₃, AcMeE₃, 6-ketoF₁, MeF₁, AcF₁, AcMeF₁, 6-ketoF₂, MeF₂, AcF₂, and AcMeF₂, The latter, together with other previously known compounds, undoubtedly make a contribution to the healing properties of thermal springs.Pacific Ocean Institute of Organic Chemistry, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 869–874, November-December, 1996. Original article submitted August 14, 1995; revision submitted August 12, 1996.     

Photochemistry of acetylenic derivatives of aromatic amines. Communication 1. Photolysis products of P-ethynyl-N,N-dimethylaniline in carbon tetrachloride

Conclusions During photolysis of p-ethynyl-N,N-dimethylaniline in CCl₄, products are formed that are exclusively due to a reaction at the triple bond and amino group, without affecting the aromatic ring: p-dimethylaminoacetophenone, N-methyl-N-(p-ethynylphenyl)-carbamoyl chloride, N-methyl-N-[p-(-chlorovinylphenyl)]-carbamoyl chloride, p-dimethylamino--chlorostyrene, and p-dimethylamino-,-dichlorostyrene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1163–1166, May, 1986.     

A further study of the substrate specificity in the reduction of 20-oxosteroids with a culture ofActinomyces roseochromogenus

Conclusions A culture ofActinomyces roseochromogenus ATCC 3347 reduces 17-hydroxy- and 16, 17-epoxy-20-oxopregnenes to the corresponding 20-alcohols, but is incapable of reducing 17-acetoxy-, 17-methyl-, and 16-methylprogesterones or 17-unsubstituted 20-oxopregnenes. The results obtained show that the presence of the side chain in a conformation favorable for the formation of 20-alcohols in the reduction of 20-oxosteroids with complex metal hydrides is in itself insufficient for the reduction of the 20-oxosteroids by a culture ofActinomyces roseochromogenus, which also reduces the 20-oxo group of 17-pregnenes.Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 38–47, 1970     

Transformed steroids 129. Synthesis of 6α-methyl-16α,17α-cyclobutanoprogesterone

Conclusions A synthesis of 6-methyl-16.17-cyclobutanopregn-4-ene-3,20-dione was carried out by opening the 5,6-oxide ring with a Grignard reagent, with preliminary protection of the 20-keto group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2151–2154, September, 1982.     

Dynamic shear modulus in the splitting region of poly(alkyl methacrylates)

A systematic study of the dynamic shear modulusG ^*=G+G in three poly(alkyl methacrylates) (PEMA, PnPMA, PnBMA) at frequencies between 0.001 and 500 rad/s is presented. As the splitting frequencies _s are low, aging effects can be observed in the splitting region. There is a systematic shift of the splitting frequency _s to lower values with increasing length of the alkyl side group. In PnBMA a separate shear appearance is observed about two frequency decades below the local mode . This is discussed in terms of the concept of minimal cooperativity. Aging effects are: Shift of the maximum loss frequency to lower values, peak sharpening of the relaxation, and intensity changes of and . These effects are discussed in terms of the sequential aging concept. Aging leads to a pronounced bending of the traces upwards from the equilibrium line in the Arrhenius diagram. These non-equilibrium phenomena are promoted by the small slope m=d(log )/dT of the trace in the splitting region.Dedicated to Prof. E. W. Fischer at the occasion of his 65th Birthday Lieber Herr Fischer, die Hallenser Polymerphysiker danken Ihnen aufrichtig für die warmherzige und effektive Förderung der Polymerwissenschaften im Raum Halle-Merseburg.     

Complex polarizability as used to analyze dielectric relaxation measurements

The effect of representing dielectric properties in terms of the complex polarizability ^c = – i is examined. Loss curves ( and tan ) are shifted towards higher frequencies, revealing the existence of new relaxations and allowing the clarifications of ones already known. We have calculated the shift ratios (at maximum or tan )/ (at maximum or tan ) from the more conventional empirical equations representing the dielectric behavior. Some examples are given.     

Study of lactams. VI. Synthesis of 6-substituted purino [8, 9-11, 22]isoindol1nes

It is shown with 1-ethoxyisoindolenine that the reaction of lactim ethers with -amino--cyanoacetamide also extends to partly aromatized lactim ethers, although these react much less readily. Condensation of 1-ethoxyisoindolenine with -amino-cyanoacetamide gives 4-carbamido-5-aminoimidazo[1, 2-1, 2]isoindoline, from which a new series of purinoisoindioline derivatives is synthesized.For part V see [2].     

Steroid compounds of marine sponges. VII. Preparation of derivatives of sokotrasterol and halistanol sulfates and structure-activity interrelationships among these compounds

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.     

Synthesis of derivatives of the androstane series

Summary Hydrazones and symmetrical dihydrazones of 2-methyltestosterone and its 17-methyl and 17-ethyl derivatives have been synthesized.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 5, pp. 354–359, 1966     

Synthesis of α,α′-bisdialkylphosphonoisopropylnitroxyls

Conclusions Some,-bisdialkylphosphonoisopropylnitroxyl radicals were obtained by the thermolysis of dialkyl -nitrosoisopropylphosphonates and isolated in the pure state.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1867–1868, August, 1979.