Synthesis and Chemical Transformations of 2-imino-2,5-dihydrofurans

Chemistry of Heterocyclic Compounds - 2-Imino-2,5-dihydrofurans are a highly valuable class of heterocyclic compounds that show versatile biological activity and are used in diverse fields of...     

Production of heavy nuclei in the interaction of <Superscript>7</Superscript>Li ions with copper nuclei at an energy of 35 MeV per nucleon

The absolute values of the cross sections for the production of target fragments in the interaction of copper with ⁷Li ions at an energy of 35 MeV per nucleon were measured. The measurements were performed by recording the yields of radioactive nuclear residues with the aid of a semiconductor detector from ultrapure germanium. The charge and isobaric distributions in the mass-number range 22–69 amu were used to deduce the mass yield of reaction products and to calculate the total interaction cross section. The results are presented that were derived from a comparison with data obtained for ¹²C + Cu reactions and with estimates based on theoretical models.     

The structure of 4-anilinopiperidine analgesics. III. The structure of the acid sulfate of 1(e)-(2-phenethyl)-2(e), 5(e)-dimethyl-4(e)-(N-propylylanilino) piperidine

Institute of Fine Organic Chemistry, Academy of Sciences of the Armenian SSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 2, pp. 141–145, March–April, 1990.     

The binding of ethidium bromide with DNA: interaction with single- and double-stranded structures

The pH-induced helix-coil transition of DNA and its complexes with EtBr is carried out at acidic pH in a wide interval of change of concentration ratio of EtBr/DNA. The binding isotherms of EtBr on double and single-stranded DNA at pH = 7.0 and pH = 3.0 (t = 25(o)C) are obtained by absorption and fluorimetric methods. Binding constants (K) and number of bases (n), corresponding to one binding site were determined. Non fluorescent "strong" complex with ds-DNA at pH = 7.0 and t = 25(o)C as well as "strong" and "weak" complexes with ss-DNA at pH = 3.0 and t = 25(o)C are revealed.     

Structure of 4-anilinopiperidine analgesics. I. The structure of the 2:1 solvate of 1(e)-(2-phenethyl)-2(e),5(a)-dimethyl-4(e)-(N-propionylanilino)-piperidine bisulfate monohydrate with cyclohexanone

An x-ray diffraction structural analysis was carried out using Cu radiation with 2975 reflections, 64° to R=0.073 for the bisulfate of the major component of the narcotic analgesic, phenaridine (1-(2-phenethyl)2,5-dimethyl-4-(N-propionylanilino)-piperidine citrate). The crystals studied obtained from cyclohexanone are a double solvate containing 1/2 randomly disordered cyclohexanone molecule and one water molecule per formal salt unit. The unit cell parameters for the monoclinic crystals are as follows: a=15.231(2), b=14.946(2), c=13.070(2) Å, -104.23(1)°, space group P2₁/c, Z=4. The methyl groups in the compound studied occupy the 2-equatorial and 5-axial positions relative to the piperidine ring. Taking account of the equatorial positions of the substitutents at the 1- and 4-positions of the piperidine ring, the compound designated should be designated the rel-(1R,2R,4S,5R) isomer. The cation has an extended conformation with ordinary geometric parameters. The relative arrangement of the pharmacophoric groups in the cation (benzene rings A and F, piperidine ring D, and the amide fragment) is similar to that for the groups in T-shaped morphine-like molecules.Institute of Fine Organic Chemistry, Academy of Sciences of the Armenian SSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 5, pp. 102–107, September–October, 1989.     

Phosphonioethylation of phenylhydrazine and hydroxylamine and selected properties of the resulting derivatives

The reactions of phenylhydrazine and hydroxylamine with (-X-ethyl)triphenylphosphonium salts (X = Ph, Ph₃P⁺Br^–) (1, 2) afforded the corresponding -N-ethyl-substituted triphenylphosphonium salts (3, 4). The reaction of triphenyl(2-phenylhydrazinoethyl)phosphonium bromide 3with an aqueous solution of NaOH in benzene afforded a statistical mixture of the nisand transisomers of 2-(diphenylphosphoryl)acetaldehyde phenylhydrazone. (2-Hydroxyaminoethyl)triphenylphosphonium bromide reacted with sodium methoxide to give O-phosphobetaine.     

Integral representation and embedding theorems for <Emphasis Type="Italic">n</Emphasis>-dimensional multianisotropic spaces with one anisotropic vertex

We prove embedding theorems for the multianisotropic Sobolev spaces generated by the completely regular Newton polyhedron. Under study is the case of the polyhedron with one anisotropic vertex. We obtain a special integral representation of functions in terms of the tuple of multi-indices of the Newton polyhedron.     

Conductivity of composite materials based on Me2(WO4)3 and WO3 (Me = Sc,In)

Composites {Me₂(WO₄)₃ ? xWO₃} (Me = Sc, In) (x = 0.5–99%) are synthesized and characterized by XRD and electron microscopy methods and also by the density and specific surface measurements. Temperature dependences of the total conductivity of composites are measured. The contributions of σ_tot and σ_el are assessed by the $\sigma (a_{O_2 } )$ and EMF methods. The concentration dependences of conductivity and activation energy are plotted based on the σ_tot and σ_ion data. It is shown that (a) in the interval x = 0–30 vol % WO₃ (0–70 mol %), the conductivity is independent of composition and the ionic component prevails; (b) in the interval x = 60–94.5 vol % (90–99 mol %), the electron conductivity prevails and increases with the increase in x; (c) in the x interval of 30–60 vol % WO₃ (70–90 mol %), the conductivity is mixed, i.e., electron(n-type)-ionic; the latter region represents the transition interval from ionic to electron conductivity as x increases. These data are compared with the results obtained earlier for MeWO₄-WO₃ composites (Me = Ca, Sr, Ba). As regards the structural topology, the {Me₂(WO₄)₃ ? xWO₃} composites pertain to the randomly distributed type. It is shown that in contrast to {Me^IIWO₄ · xWO₃} composites, the composites under study do not form the nonautonomous interface phase with the high ionic conductivity. The possible reasons for the observed differences in the topology and the conduction type of composites based on MeWO₄ and Me₂(WO₄)₃ are analyzed.