bluuebunny/crossref_metadata_2025 huggingface dataset:
Die Autoxidation von metallischem Kupfer und Kupfer(I)-Verbindungen / Investigation on Autoxidation of Metallic Copper and Copper(I) Compounds by Different Methods
Authors: Horner Leopold , Pliefke Engelbert
Published: February 2015

The corrosion of copper granules under controlled conditions (2.5% NaCl solution, pH 4 buffer, O2) was studied using a) the rate of uptake of oxigen and b) the pH stat method. Cu2+ ions catalyse the corrosion of copper. The surface area of the copper and the temperature influence the rate of corrosion in the expected manner. Experiments in light and dark showed little variation in the results.

The results obtained by measuring the O2 uptake and using the pH stat method were confirmed and complemented by electrochemical measurements. (Steady potential/time curves, current/voltage curves, measurement of the polarisation resistance and estimation of Cu2+ during corrosion via a Cu2+ sensitive electrode.) The influence on the corrosion of F-, CI-, Br- and I-, mineral acid concentration and other inorganic ions was also studied under standard conditions. To ensure the correctness of the interpretation of the results (see reaction scheme), the autoxidation of CuCl and CU2O was also studied under standard conditions.

The experimental results are consistent with the steps (1)-(4) in the reaction scheme. The fastest step is clearly the oxidation of Cu1+ , which is continuously supplied via the copper surface. The interpretation here presented forms the basis for the understanding of the inhibition of corrosion exhibited by a number of organic compounds.
Crystal Structure and the Radiation-Induced Free-Radical Chain Reaction of 2-Deoxy-β-D-erythro-pentopyranose in the Solid State
Authors: Schuchmann Man Nien , Sonntag Clemens von , Tsay Yi-Hung , Krüger Carl
Published: February 2015

The crystal structure of 2-deoxy-β-D-enrythro-pentopyranose (1) was reexamined by X-ray crystallographic studies. In crystalline 1, a radiation-induced chain reaction occurs with the only product being, 2,5-dideoxy-D-enrythro-pentonic acid (4). In the chain propagating step leading to 4, an H atom is transferred over a distance of ≤ 3.3 Å as taken from interatomic distances in the unperturbed crystal. The crystal structure clearly indicates the direction by which the chain reaction proceeds through the crystal. The strong temperature dependence of G(4) is discussed in terms of temperature effects on chain initiation, propagation and termination rates.
Benzoylierung an 3-8ubstituierten 4-Hydroxy-2-chinolonen und 4-Hydroxycumarinen / Benzoylation of 3-Substituted 4-Hydroxy-2-quinolones and 4-Hydroxycoumarines
Authors: Stadlbauer Wolfgang , Kappe Thomas
Published: February 2015

The reaction of 3-aryl- or alkylsubstituted 4-hydroxy-2-quinolones or 4-hydroxycoumarins (3a-k) with benzoylchloride afforded the 4-benzoyloxy-2-quinolones or 4- benzoyloxycoumarines 2a-k. Only in one case the 3,3-disubstituted quinolinedione 4 has been isolated, which rearranges to 2a under thermal or basic conditions.
Pseudobasen aus Chinolinium-Salz und Alkoxiden / Pseudobases from Quinolinium-Salts and Aleoxides
Authors: Gündel Wolf-H. , Berenbold Helmut
Published: February 2015

The quaternary 3-cyano-quinolinium salt (1b) reacts in aqueous buffer solution (pH 7.5-12) to oxy-di(1.4-dihydroquinoline) (7), which gives on addition of alcohols or oximes in high yields the alcoxy-dihydroquinolines (8a-c) or dihydroquinolyl-oximethers (8d-f).
Silyl-Assistierte Etherspaltung bei Radikalkationen von Hydroxylaminderivaten [1] / Silyl-Assisted Ether Cleavage in Radical Cations of Hydroxylamine Derivatives [1]
Authors: Ciommer Bernhard , Schwarz Helmut , Maaroufi Azzedine , Reetz Manfred T. , Levsen Karsten
Published: February 2015

It is demonstrad by means of various mass spectrometric techniques that the dissociative ionization of N.N-bis-silylated hydroxylamine derivatives (5a) and (5b), giving rise to the cleavage of the (O-C) bond, is anchimerically assisted by migration of the trimethylsilyl group to the ether oxygen, thus generating ion (7).
Preparation and Some Reactions of Phenylmercury Thio- and Dithiocarboxylates
Authors: Kato Shinzi , Hattori Eiji , Sato Hiroyuki , Mizuta Masateru , Ishida Masaru
Published: February 2015

It has been found that the reaction of diphenylmercury with an equimolar amount of thio- or dithio acids gave the corresponding phenylmercury thio- (1) or dithiocarboxylates (2), quantitatively, which further react with thio- or dithio acids to give mercury bis (thio-) (3) or bis(dithiocarboxylates) (4). The phenylmercury dithio salts (2) were found to be the very useful thioacylating agents for primary and secondary amines. The reaction of mercury bis(thiocarboxylates) (3) with dithiocarboxylic acids gave the unsymmetrical thio- and dithiocarboxylic acid mercury salts [RC(O)SHgS(S)CR′]j (5) in good yields.
Darstellung und Spektroskopische Charakterisierung von [4.7-13C2]-Azulen/ Preparation and Spectroscopic Characterisation of [4,7-13C2] Azulene
Authors: Zeller Klaus-Peter , Berger Stefan
Published: February 2015

A multistep synthesis of [4.7-13C2] azulene (10) using Na13CN as source for the labelled carbon atom is described. The electron impact induced elimination of acetylene from the molecular ions of 10 proceeds with almost statistical participation of the carbon atoms, thus indicating an extensive scrambling of the azulene carbon skeleton prior to fragmentation. From the 13C NMR spectrum of 10, 13C13C spin spin coupling constants have been determined. The measured values confirm our earlier interpretation of the transmission of the 13C13C spin spin coupling constants in terms of a π-mechanism.
Isolation of the Geminal Bis(amido) Derivative, N4P4(NH2)2Cl6, from the Reaction of N4P4Cl8 with Ammonia
Authors: Ramabrahmam P. , Krishnamurthy S. S. , Woods M.
Published: February 2015

Geminal Bis (amido)hexachlorocyclotetra -phosphazene, Aqueous Ammonia Synthesis, 31P NMR The geminal isomer of N4P4(NH2)2Cl6 is obtained from the reaction of the octachloride, N4P4Cl8, with aqueous ammonia in diethyl ether in the presence of anhydrous sodium sulphate. The compound is characterised by 31P NMR spectroscopy and by conversion to its dimethyl -amino derivative, N4P4(NH2)2(NMe2)6.
Dialkylallenylidenekomplexe mit Pentacarbonylfragmenten der VIb Metalle/Dialkylallenylidene Complexes with Pentacarbonyl Fragments of VI b Metals
Authors: Berke Heinz , Härter Peter , Huttner Gottfried , Zsolnai Laszlo
Published: February 2015

In the context of the synthesis of allenylidene compounds, the reaction of methylpropiolate with a (OC)5CrO(C2H5)2 complex was investigated. The species pentacarbonyl- (methylpropiolate)chromium(0) (1), 2,4-bis(methoxycarbonyl)-cyclobut-2-en-1-yliden-1- pentacarbonylchromium(0) (2) and cis-2,4-dimethoxycarbonyl-1,3-butadien-1 -yliden-1 - pentacarbonylchromium (3) were isolated. Attempts to synthesize allenylidene complexes from 1 were unsuccessful. Di-iso-propyl or di-tert-butylallenylidene complexes with chromium or tungsten centers (4a, 4b, 5a, 5b) were finally obtained by the photochemical reaction of pentacarbonylpropargylates, (OC)5MC(O)C ≡ CCR2O2-, M = Cr, W, and subsequent desoxygenation. The complexes 4 a, b were characterized as triphenylphosphane adducts, di-iso-propylallenylidenetriphenylphosphorane complexes (6a und 6b). The structure of 6 a was determined by X-ray methods.
Darstellung und Charakterisierung von Triphenylbleiderivaten einiger Aminosäuren/Preparation and Characterization of Triphenyllead Derivatives of Some Amino Acids
Authors: Roge Gerd , Huber Friedo
Published: February 2015

Triphenyllead derivatives Ph3PbL (HL = glycine, alanine, phenylalanine) and (Ph3Pb)2L′ (H2L′ = aspartic acid) have been prepared from Ph3PbOH and the appropriate amino acid. PH3Pb-leucinate has been synthesized from Ph3PbCl and Tl(I)-leucinate. From IR data structural proposals are inferred: Ph3Pb-glycinate is polymeric through monodentate carboxylate and coordinating NH2; Ph3Pb-alaninate, -phenylalaninate, and -leucinate contain bidentate carboxylate and non-coordinating NH2 groups and are probably monomeric. For (Ph3Pb)2-aspartate and (Me3Sn)2-aspartate a structure with coordinating NH2 and mono-and bidentate carboxylate groups is proposed.
The Crystal and Molecular Structure of the 1:2 5,10-Dihydro-5,10-diethylphenazine-(E2P)-2,2′-(2,5-Cyclohexadiene-1,4- diylidene)bispropanedinitrile (TCNQ) Complex
Authors: Dietz K. , Endres H. , Keller H. J . , Moroni W.
Published: February 2015

C16H18N2·2 C12H4N4, C40H26N10, Mr = 646.7, crystallizes in space group P1̄ with a = 6.843(2), 6 = 7.845(3), c = 16.208(7) Å, α = 84.59(3), β = 81.63(3), γ = 75.75(3)°, V = 832.9 Å3 , Z = 1, dc = 1.29 Mgm-3 . Final weighted R = 0.107 based on 2894 reflections. The structure consists of stacks of TCNQ π-dimers with interplanar distances of 3.25(1) Å within a dimer and 3.54(1) A between dimers. The phenazine species do not form stacks and show no electronic interaction with adjacent E2P or TCNQ molecules.
The Structure of the Cyclopentathiazenium Cation (S5N5
+) - a MNDO Investigation
Authors: Gleiter Rolf , Bartetzko Richard
Published: February 2015

The total energies, heats of formation (⊿Hf), bond lengths and bond angles of four isomers of S5N5
+ (1) have been calculated using the MNDO method. The heart shaped and azulene like structures 1 e and 1 f have been found to be the most stable isomers with about equal energies.
cis -Bis(2 -methoxyphenyl)bis (triphenylphosphan)platin(II) Synthese, Kristall- und Molekülstruktur und thermisches Verhalten/cis-Bis(2-methoxyphenyl)bis(triphenylphosphane)platinum(II) Synthesis, Crystal and Molecular Structure and Thermal Stability
Authors: Debaerdemaeker Tony , Klein Heinz-Peter , Wiege Manfred , Brune Hans Albert
Published: February 2015

cis-Bis(2-methoxyphenyl)bis(triphenylphosphane)platinum(II) has been synthesized and its molecular and crystal structure determined by X-ray analysis. The structure is discussed with respect to the transition state of the thermal reductive elimination of 2,2′ -bismethoxybiphenyl.
Identification of Protected Deoxyribonucleotides by Field Desorption Mass Spectrometry in Fractions from High Performance Liquid Chromatography
Authors: Schiebel Hans Martin , Schulten Hans-Rolf
Published: February 2015

Protected deoxyribonucleotides were identified by field desorption mass spectrometry in eluate fractions from high performance liquid chromatography. The production of abundant cationized molecules and the formation of structural significant fragments by thermally/field induced processes allowed a direct and unambiguous identification of the synthesized products. In addition, indications can be obtained on both organic and inorganic impurities.
Das dynamische Verhalten des 1-Methyl-1-benzothiepinium-Ringsystems/The Dynamic Behaviour of the 1-Methyl-1-benzothiepinium Ring System
Authors: Hofmann Hans , Dickert Franz
Published: February 2015

By 1H NMR spectroscopy the stereochemistry of the 1-methyl-1-benzothiepinium ring system was investigated both in thermodynamic and kinetic respects. It was shown that in solution a rapid mutual conversion of the boat shaped seven membered ring system with exo-respectively endo-S-methyl group occurs via a ring inversion and not by a pyramidal inversion at the sulfonium ion. At room temperature predominantly the conformation with the exo-S-methyl group is present.
Conformational Studies of R-(+)-2-Alkylidene-and R-(—)-2-Benzylidene-5-methylcyclohexanones
Authors: Anand Devinder K. , Hargreaves Michael K. , Khan Mohsin A.
Published: February 2015

The cis and trans 2-alkylidene-5-methylcyclohexanones have been separated and distinguished. 2-Benzylidene-5-methylcyclohexanone was also prepared in both forms. The CD, ORD, UV and IR spectra are recorded and discussed. The NMR data include solvent and temperature effects.
Konfigurations-Bestimmung von Isomeren des Methyl 4-O-Acetyl-2.3-O-(1-phenylethyliden)-α-L-rhamnopyranosides/ The Configuration of Isomeres of Methyl 4-O-Acetyl-2,3-O-(1-phenylethylidene)-α-L-rhamnopyranoside
Authors: Lotter Hermann , Lipták András
Published: February 2015

The diastereomeric 2,3-O-[2-phenyl-2-methyl-1,3 dioxalanes] of methyl-α-L-rhamno-pyranosides were synthesised for the first time. The stereochemical characterisation was carried out by X-ray analysis. Evaluation of the X-ray data and comparison with NMR data indicated that the same configuration exists in the crystalline state as in solution.
Darstellung von 2-Amino-1.3.2λ3(λ5)-dioxaphospholanen / Synthesis of 2-Amino-1,3,2λ3 (λ5)-dioxaphospholanes
Authors: Storzer Werner , Schomburg Dietmar , Röschenthaler Gerd-Volker
Published: February 2015

The 2-amino-4,4,5,5-tetrakis(trifluoromethyl)-1,3,2λ3-dioxaphospholanes 1 a - c are synthesized by reacting halogenoaminophosphines with dilithiumperfluoropinacolate, whereas 1 d-f are obtained from 2-chloro-4,4,5,5-tetrakis(trifluoromethy 1) -1,3, 2λ3-dioxaphospholane and the aminosilanes RNH(SiMe3) (R = t-Bu, SiMe3) or the amide (Me3Si)2NLi, respectively. Addition of chlorine to 1 a-f yields the covalent 2,2-dichloro-1,3,2 λ5-dioxaphospholanes 2 a-f which furnish the spirophosphoranes 3 a-f upon reaction with dilithiumperfluoropinacolate. The X-ray structure analysis of 3 a exhibits an almost ideal trigonal bipyramid having a very short P-N bond distance (1.590 Å) and H ··· O distance (2.34 Å).
Über die inhibierende Wirkung grenzflächenaktiver Stoffe auf die polarographische Reduktion von Cd2+ -, Zn 2+ -und Co 2+ -Ionen in wasser-methanolischen und methanolischen Lösungen / On the Inhibition Effect of Surfactants on the Polarographic Reduction of Cd 2+ , Zn 2+ and Co 2+ Ions in Aqueous Methanolic and Methanolic Solutions
Authors: Markopoulos J. , Jannakoudakis D.
Published: February 2015

The inhibition effect of tri-n-octylphosphine oxide (TOPO), triphenylarsine oxide (TAsO), triphenylphosphine oxide (TPO), triphenylarsine (TPAs) and triphenylphosphine (TPP) on the polarographic reduction of Cd2+, Zn2+ and Co2+ ions in aqueous methanolic and methanolic solutions has been studied.

A different action of the inhibitors was obtained for each reducible ion. No change in the mechanism of the cathodic reductions has been observed. In all systems TOPO appeared to be the strongest inhibitor.
Schwefel(VI)-oxid-chlorid-imide und Schwefel(VI)-oxid-fluorid-imide [1] / Sulfur(VI)-oxide-chloride-imides and Sulfur(VI)-oxide-fluoride-imides [1]
Authors: Mews Rüdiger , Kricke Peter , Stahl Ingo
Published: February 2015

At room temperature in the presence of CsF sulfur-oxide-chloride-fluoride-imides RfNSOFCl (8) (Rf = CF3, C2F5, i-C3F7, C6F5) are formed from N-perfluoroalkyl-sulfinyl-imides and Cl2. At prolonged reaction times or higher temperatures the chloride is ex-changed and the difluorides RfNSOF2 are isolated in high yields. In the same way (CF3)2CFNS(O)ClCF3 (12) and (CF3)2CClNS(O)ClCF3 (13) are obtained from (CF3)2C = N-S(O)CF3 (9) and Cl2/CsF. 12 can be fluorinated by CsF to give (CF3)2CFNS(O)FCF3 (14). 14 is also observed, when fluorine is added to 9 via XeF2 in the presence of BF3, but mainly C-S-bond cleavage occurs. SF5NS(O)FCF(CF3)2 (19) was identified by spectroscopic methods from the reaction of SF5NSOF2 and CF3CF = CF2 in the presence of CsF.
Neue Verbindungen mit der Ca9Mi4Bi9-Struktur: Zur Kenntnis von Ca9Cd4Bi9, Sr9Cd4Bi9 und Ca9Zn4Sb9 / New Compounds with the Ca9Mn4Bi9 Structure: Ca9Cd4Bi9, Sr9Cd4Bi9, and Ca9Zn4Sb9
Authors: Brechtel Erwin , Cordier Gerhard , Schäfer Herbert
Published: February 2015

The new compounds Ca9Cd4Bi9, Sr9Cd4Bi9 and Ca9Zn4Sb9 crystallize in the orthorhombic system (Pbam) in the Ca9Mn4Bi9 structure with the following constants:

Ca9Cd4Bi9: a = 2258 ± 2 pm, b = 1278 ± 1 pm, c = 474 ± 1 pm.

Sr9Cd4Bi9: a = 2347 ± 2 pm, b = 1327 ± 1 pm, c = 489 ± 1 pm.

Ca9Zn4Sb9: a = 2192 ± 2 pm, b = 1250 ± 1 pm, c = 454 ± 1 pm.
cis-Dichloro-(1 ,5-bisdiphenylphosphanopentane)platinum(II). Synthese, Krystall– und Molekülstruktur / cis-Dichloro-(1 ,5-bisdiphenylphosphanopentane)platinum(II). Synthesis, Crystal and Molecular Structure
Authors: Klein Heinz-Peter , Thewalt Ulf , Zettlmeißl Heinz , Brune Hans Albert
Published: February 2015

The title compound has been prepared in high yield from K2[PtCl4] and 1,5-bis(diphenylphosphano) pentane in dry CH2Cl2. The crystals are monoclinic, space group P21/c with lattice parameters a = 11.733(3), b = 17.229(5), c = 13.743(4) Å, and β= 92.37(3)°; Z = 4.

An X-ray analysis shows that the complex is monomeric and that it has a planar cis-configuration.
Electron Spin Resonance Studies on Conformational Changes of the Sarcoplasmic Reticulum Ca2+ – ATPase Induced by Synergistic Action of Calcium and ATP
Authors: Laggner Peter , Suko Josef , Punzengruber Christian , Prager Rudolf
Published: February 2015

Changes in motional properties of the -SH group environment in sarcoplasmic reticulum ATPase [1] induced by addition of specific ligands to sarcoplasmic reticulum membrane vesicles were investigated systematically by electron spin resonance (e.p.r.) spectroscopy. Alternatively, two kinds of iodoacetamide analog spin labels, 4-(2-iodoacetamido)- 2,2,5,5-tetramethyl-1-pyrrolidinyl-N-oxyl (label I) and 4-(2-iodoacetamido)-2,2,6,6-tetramethyl- 1-piperidinyl-N-oxyl (label II) were used. The labeling conditions were chosen such that less than three moles of -SH groups per mole of ATPase reacted with the spin labels.

A marked increase in isotropic motion of either spin label was observed on addition of calcium in millimolar concentrations plus ATP or β-γ-methylene ATP. Qualitatively similar but smaller changes were also observed with inosine 5'-triphosphate (ITP), acetylphosphate, or ADP in the presence of calcium. These effects were independent of added magnesium. The spectral changes induced by β-γ-methylene ATP, which binds to the ATPase but is not hydrolyzed, and those of calcium plus ADP suggest a conformational change due to simultaneous binding of these ligands in the absence of enzyme phosphorylation. These changes in e.p.r. spectra were different in quality and magnitude from those observed upon separate binding of calcium or adenine nucleotides.

The two spin labels, differing only in their numbers of heterocyclic ring atoms, were found to reflect environmental changes in different ways. This demonstrates the usefulness of employing different spin labels to detect and interpret structural transitions in macromolecular assemblies.
Taifine, a New Alkaloid from Ruta chalepensis L
Authors: El-Tawil B. A. H. , El-Beih F. K. A. , Budzikiewicz H. , Möhr N.
Published: February 2015

From Ruta chalepensis L. (Rutaceae) a new alkaloid, taifine, has been isolated. Its structure has been determined as 9-ethyl-7-methoxyfuro[2,3-b]quinolone-4.
Untersuchung der symmetrischen Phosphat-Valenzschwingung in gemischten Calcium-Strontium-Apatiten / Investigation on the Symmetric Phosphate Stretching Vibration in Mixed Calcium -Strontium -Apatites
Authors: Apella M. C. , Etcheverry S. B. , Baran E. J.
Published: February 2015

The distortive effects produced by the sub-stitution of Ca(II) for Sr(II) upon the PO4
3-ions in the Ca10(PO4)6(OH)2 and Ca10(PO4)6F2 lattices have been investigated. The study is based on the behaviour of the symmetric stretching frequency of the anion in series of solid solutions containing both cations.
Solid Phase Peptide Synthesis by Four Component Condensation: Peptide Formation on an Isocyano Polymer Support
Authors: Arshady Reza , Ugi Ivar
Published: February 2015

Coupling of various protected amino acids or small peptides on an isocyano polymer and in the presence of 1 -methyl-3-formylindole demonstrates the feasibility of peptide formation by four component condensation on a polymer support, and the final peptide is detached from the resin by 50% trifluoroacetic acid in aceto-nitrile at room temperature.
Verteilung und Valenz der Kationen in Spinellsystemen mit Eisen und Vanadium, III Röntgenographische und Mößbauer-spektroskopische Untersuchung des Spinellsystems ZnFeVO4-Fe3O4 / Distribution and Valence of the Cations in Spinel Systems with Iron and Vanadium, III X-ray Investigation and Mössbauer Spectra of the Spinel System ZnFeVO4-Fe3O4
Authors: Riedel Erwin , Anik Hümeyra , Dützmann Till
Published: February 2015

The spinel system Zni_zFe2:[Fei+2;Vi_I]04 has been prepared by heating mixtures of ZnFeV(>4 and Fe3Ü4 at 1000 °C. The lattice constants, the oxygen parameters and the Mössbauer parameters show that a transition from a nearly normal to an inverse distribu-tion of Fe(II) and Fe(III) exists.
Übergangsmetallbenz - in-Komplexe. Dynamisches Verhalten von [Ta(C6H5)4(C6H4)a(Li • OC4H10)3] / Transition Metal Benzyne Complexes. Fluxional Behaviour of [TA(C6H5)4(C6H4)2(Li·OC4H10)3]
Authors: Sarry Brigitte , Schaffernicht Rolf
Published: February 2015

Products of the reaction between MBr5 and PhLi are proved to be benzyne complexes [M(C6H5)4(CeH4)2(Li · OC4H10)n], (M = Nb, Ta, W). Analysis of the temperature dependent 1 H and 7 Li NMR Spectra of [Ta(C6H5)4(C6H4)2(Li·OC4H10)3] are interpreted on the basis of square antiprismatic/dodecahedral structure with facial C6H4 groups.
The 51V NMR Spectra of Some Oxo-, Peroxo-, Nitrosyl- and Hydroxylamidovanadium Complexes
Authors: Rehder Dieter , Wieghardt Karl
Published: February 2015

The 51V NMR spectra are recorded for 3 dinuclear complexes {VO(ONR2)2μ - O and 13 mononuclear vanadium (+ V) and (+III) chelate complexes of the general formula [VXYZ]q, where X = O2-, NO-; Y = O2-, O2
2-, R2NO-; and Z = picolinate-(pic), dipicolinate2- (dipic), nitrilo-tri(2-propanolate)3-, and o-phenanthroline (phen). Shielding of the 51V nucleus increases as O2- is replaced for NO-, and in the series (O2- + dipic) < (2 O2
2- + pic) < (R2NO- + dipic) < (2 H2NO- + phen) < (2 H2NO- + pic); Et2NO- < H(Me)NO- < H2NO-; and (dinuclear complexes) C5H10NO- < Bz2NO- < Et2NO- These trends are explained on the basis of variations of molecular parameters correlated to electronic and steric factors associated with the ligands. Line widths of the 51V NMR signals are discussed in terms of influences originating from variations of the electric field gradient and the molecular correlation time
4.5 -Dicyano-1.3.2λ3-diazaphospholat - ein anionisches, als Monomer stabiles 1.3.2-Diazaphosphol [1] / 4,5-Dicyano-1,3,2 λ3-diazaphospholate - an Anionic 1,3,2-Diazaphosphole, Stable as a Monomer [1]
Authors: Schmidpeter Alfred , Karaghiosoff Konstantin
Published: February 2015

Diamino-maleodinitrile and P(NMe2)3 condense at room temperature to the dimethyl -ammonium salt of the dicyano-1,3,2-diazaphosphole. Other products may result under different conditions. Mel methylates the ambivalent diazaphosphole anion at nitrogen.
Non-Statistical Label Distribution in Biosynthetic 13C Enriched Amino Acids
Authors: Bengsch E. , Grivet J.-Ph.
Published: February 2015

A combined 13C nuclear magnetic resonance and field desorption mass spectrometric investigation of algae grown on 13CO2 has shown that the isotopic enrichment of amino acids extracted therefrom is neither uniform nor statistical. The use of these two independent techniques allows a new, detailed and accurate insight into the label distribution resulting from biosynthesis. The observed deviations from the statistical abundances are systematic. A system for classifying each member of the complex ensemble of isotopic species has been devised, so that the isotopomers may be ordered according to their relative probability of occurrence.
Studies on Vitamin B12 and Related Compounds, 54 Synthesis of 2-Hydroxyethylcobalamin from Ethylene and Vitamin B12r under "Oxidizing-Reducing" Conditions
Authors: Schrauzer G. N. , Grate Jay W. , Maihub Abdussalam , Xu Hui Bi
Published: February 2015

Reaction of ethylene with hydroxyl radicals under reducing conditions produces radicals which are trapped by Vitamin Bi2r, yielding 2-hydroxyethylcobalamin. Vitamin B12,
Difluorooxoschwefelimidato-metallate, [Ag(NSOF2)2]- und [M(NSOF2)4
2-, (M = Cu, Zn, Mn) / Difluorooxosulfurimidato-metallates, [Ag(NSOF2)2]- and [M(NSOF2)4]2- (M = Cu, Zn, Mn)
Authors: Eisenbarth Rainer , Sundermeyer Wolfgang
Published: February 2015

Difluorooxosulfurimidato-metallates, [Ag(NSOF2)2]- and [M(NSOF2)4]2-, (M = Cu, Zn, Mn), could be obtained by reaction of AgNSOF2 with (C6H5)4AsNSOF2 and the tetrabromo complexes [(CeH5)4P]2MBr4, respectively
Kristallstruktur und spektroskopische Untersuchungen von Dithiomalonsäurediamid H2C(CS-NH2)2: Ein Beispiel für eine Helixstruktur / Crystal Structure and Spectroscopic Investigations of H2C(CS-NH2)2: An Example for an Helix Structure
Authors: Hlawatschek Hartmut , Kiel Gertrud , Gattow Gerhard
Published: February 2015

The crystal structure of dithiomalonediamide (H2C(CS-NH2)2) has been determined. The compound crystallizes in the orthorhombic space group P2nn, No. 34, with a = 4.354(3), b = 7.940(5) and c = 8.458(5) Å. The molecules are connected by S ··· H bridges to form helices along the crystallographic a axes.
Synthese von 1-Aminoalkanphosphonsäuren via Benzhydrylschiffbasen / Synthesis of 1-Aminoalkane Phosphonic Acids via Benzhydrylic Schiff Bases
Authors: Issleib Kurt , Döpfer Klaus-Peter , Balszuweit Arno
Published: February 2015

A simple synthesis of 1-aminoalkanephosphonic acids is described. The addition of diethylphosphite to alkylidene-and arylidenebenzhydrylamines yields the N-benzhydryl-1-aminoalkanphosphonic acid esters. The title compounds are formed by treatment of the N-blocked esters with hydrobromic acid. The starting amine can be recycled from the hydrylbromide.
Na6[Au2O6] - ein „Insel-Aurat" / Na6[Au2O6] - a "Soro-Aurate"
Authors: Klassen Horst , Hoppe Rudolf
Published: February 2015

Na6[Au2O6] crystallizes tetragonally with a = 9.465(1) Å, c = 4.506(1) Å, Z = 2; space group P42/mnm. The crystal structure shows planar [Au2O6]-groups systematically shifted by a/2 · √2̄ along [110], twisted relative to each other by 90°, and stacked along [001].

Effective Coordination Numbers, ECoN, and the Madelung-Part of Lattice Energy, MAPLE, have been calculated and are discussed.
On the Reactions of CF3SF4Cl, (CF3)2SF2, SF4, and OSCl2 with Trimethylsilyl Cyanide
Authors: Kumar Ramesh C. , Shreeve Jean′ne M.
Published: February 2015

A moderately stable hexacoordinated sulfur(VI) compound with four different kinds of ligands, CF3SF2(CN)2Cl, results when CF3SF4Cl is reacted with (CH3)3SiCN. The latter compound also gives F2S(CN)2 and (CF3)2S(CN)2 with SF4 and (CF3)2SF2, respectively. These tetracoordinated suifur(IV) compounds decompose rapidly at 25 °C but are stable at lower temperatures. With OSCl2 and SCl2, the white solids OS(CN)2 and S(CN)2 result. This provides a new, convenient route to S(CN)2.
Synthese und Eigenschaften von Alkyloxi-und Aryloxi-substituierten Trithiadiborolanen / Synthesis and Properties of Alkoxi and Aryloxi Substituted Trithiadiborolanes
Authors: Schmidt Max , Sametschek Erich
Published: February 2015

The first examples of the hitherto unknown 1,2,4-Trithia-3,5-diborolanes with B-O-C-bonds have been synthesized and characterised. The diiodo substituted ring (2) reacts with 2,6-dimethylphenol, to form 3,5-bis-(2,6-dimethylphenyloxi)-1,2,4-trithia-3,5-di-borolane (3) and HI. 3,5-Diethoxi-1,2,4-trithia-3,5-diborolane, 5, and C2H5I are formed via the cleavage of diethylether by 2. From 2 and diisopropylether, the corresponding 3,5-diisopropyloxi-1,2,4-trithia-3,5-diborolane (6) is formed. The unsymmetrical ethers methyl-t-butylether and methylphenylether undergo reactions with 2 resulting in the formation of 3,5-dimethyloxi-1,2,4-trithia-3,5-diborolane (8) (besides t-C4H9I) and 3,5-diphenyloxi-1,2,4-trithia-3,5-diborolane (10) (besides CH3I). The thermal stability of the new compounds is increasing with increasing size of R in the -OR group and from aliphatic to aromatic R in this group.

IR, Raman, 1H NMR and 11B NMR spectra of the compounds are reported as well as some physical and chemical properties.
Quantitative Synthesis of (C6H5)2AsF2+AsF6- and (C6H5)2AsF3 via Interaction of Benzene with Arsenic Pentafluoride
Authors: Tanzella Francis L. , Bartlett Neil
Published: February 2015

Benzene reacts quantitatively with AsF5 to give (C6H5)2AsF2 + AsF6-, the first reported aryl or alkyl fluoroarsonium(V) salt. This reacts quantitatively with CsF to give (C6H5)2AsF3 and CsAsF6. Interaction of (C6H5)2AsF3 with AsF5 reconstitutes the fluoroarsonium salt. Variable temperature 19F NMR studies show (C6H5)2AsF3 to be a rigid trigonal bipyramid, with the phenyl groups in equatorial positions.
Tl6X4S − ein neuer Chalkogenhalogenidtyp in Thalliumsulfid-Thalliumhalogenid-Systemen Tl6X4S − A New Chalcogeno Halide Type in Thallous Sulphide-Thallous Halide Systems
Authors: Blachnik R. , Dreisbach H. A.
Published: February 2015

Phase studies were performed in the system Tl2S + TlX (X = Cl, Br, I) and showed the existence of a new type of compound Tl6X4S in the quasibinary systems. In addition, in the iodide system a high temperature compound Tl3SI exists. The enthalpy of melting of Tl6I4S is given.
Tetrakis(trifluormethylthiyl)hydrazin − ein ungewöhnlich thermolabiles / Hydrazinderivat Tetrakis(trifluoromethylthiyl)hydrazin -an Unusually Thermolabile Hydrazine Derivative
Authors: Schlosser Karl
Published: February 2015

[(CF3S)2N]2 (1) prepared by irradiation of (CF3S)3N underwent homolytic N−N-bond dissociation below room temperature to give (CF3S)2N-radicals, which were identified by ESR.

The easy N−N-bond cleavage is ascribed to steric strain in 1 and electronic stabilization of 2.
1.2λ3.3λ3-Azadiphosphiridine − Synthese, Kristallstruktur und Eigenschaften / 1,2λ3,3λ3-Azadiphosphiridines − Synthesis, Crystal Structure and Proj)erties
Authors: Niecke Edgar , Nickloweit-Lüke Anke , Rüger Reinhold
Published: February 2015

1,2λ3,3λ3-Azadiphosphiridines are available by elimination of hydrogenhalide from β-and γ-functional molecular frameworks and by 1+2 cycloaddition of phosphinidenes towards aminoiminophosphanes. In contrast to other three-membered phosphorus compounds, azadiphosphiridines decompose by 2+1 cycloreversion to aminoiminophosphanes and phosphinidenes. The molecular structure of an azadiphosphiridine demonstrates the trans arrangement of the exocyclic ligands and the planarity of the endocyclic nitrogen.
Übergangsmetall-Garben-Komplexe, CXXI [1] Fluorcarbenkomplexe des Mangans / Transition Metal Carbene Complexes, CXXI [1] Fluorocarbene Complexes of Manganese
Authors: Aus dem Anorganisch-chemischen Institut der Technischen Univ Ernst Otto , Kleine Willi , Schambeck Werner , Schubert Ulrich
Published: February 2015

The reaction between CH3Cs5H4Mn(CO)3 and LiN(C2H5)2 and subsequent alkylation with [(C2H5)3O]BF4 affords CH3C5H4(CO)2MnC(OC2H5)N(C2H5)2. This carbene complex reacts with borontrihalides BX3 (X = F, Cl) to yield [CH3C5H4(CO)2MnCN(C2H5)2]BX4. Ad-dition of [(C4H9)4N]F to this cationic carbyne complex results in the formation of CH3C5H4(CO)2MnC(F)N(C2H5)2 . In the same way C5H5(CO)2MnC(F)C6H5 is prepared from [C5H5(CO)2MnCC6H5]SbCl6. Fluoride addition can be reversed by reaction of the latter carbene complex with BF3 to give [C5H5(CO)2MnCC6H5]BF4. In the X-ray structure of C5H5(CO)2MnC(F)C6H5 unusual bonding parameters are found, which are consistent with the easy cleavage of the C(carbene)-F bond.
Reaktionswege zu 3-Acyl-2-oxo-cholest-5-enen / Reaction Ways to 3-Acyl-2-oxo-cholest-5-enes
Authors: Berbalk Hans , Eichinger Karl , Heisler Günter , Bauer Rupert
Published: February 2015

Two reaction ways to 3-phenylacetyl-2-oxo-cholest-5-ene (10) as model compound for similar A-ring derivatives of steroids are investigated. The first way starts from the known 6,6-ethylenedioxy-3-oxo-5α-cholestane (1) which is reacted with phenylethinyl-magnesiumbromide to the mixture of epimeric alkinols. The crude mixture of epimers is dehydrated to 6,6-ethylenedioxy-3-phenylethinyl-5α-cholest-2-ene (2), which gives after epoxidation of the double bond and reaction of the resulting crude epoxide with 95 proz. HCOOH the fully enolic 2,6-dioxo-3-phenylacetyl-5α-cholestane (3). Because of a very low total yield of this approach to 10 this way is not further investigated. A successful reaction way starts from the known 6β-hydroxy-5α-cholestane-3-one (4). 4 is reacted with phenylethinylmagnesiumbromide, the 6β-OH group is benzoylated and the tert. alkinols dehydrated in successive steps without isolation of the non crystalline intermediate pro­ducts to 6β-benzoyloxy-3-phenylethinyl-5α-cholest-2-ene (6). Hydrolysis of 6 yields 6β-hydroxy-3-phenylethinyl-5α-cholest-2-ene (7) which is epoxidated at the double bond and the crude epoxide reacted with 95 proz. HCOOH to 6β-formyloxy-3-phenylacetyl-5α-cholestan-2-one (8). Hydrolysis of the formylgroup in 8 yields 9, which gives by acid cata­lysed dehydratisation the desired model compound 10. The structure of 10 is confirmed by its 1H NMR and UV spectra.
Molecular Complexes, V [1, 2] 1H NMR Investigation of the Caffeine Benzene Complex Followed by AUS Correction of Experimental Data Structural Requirements for Substances to Serve as Internal Reference in Investigations of Weak Complexes
Authors: Stamm Helmut , Stafe Jürgen
Published: February 2015

The 4 proton signals of caffeine, dissolved in carbon tetrachloride, were investigated as functions of benzene concentrations in a very large concentration range. Shifts of the 4 signals were measured relative to both internal and external reference. Scatchard plots of the internally referenced data were curved downwards, the degree of curving increasing from 7-methyl/8-H to 3-methyl to 1-methyl. The 1-methyl plot even showed a maximum in the observed relative shifts ⊿oi which turned to negative values for high benzene concentrations. Scatchard plots of the externally referenced data were curved upwards.

Applying AUS corrections [1, 8] to both sets of data furnished linear Scatchard plots for ah signals. The plots for the 4 protons were parallel to one another in case of the externally referenced data and not parallel for the internally referenced data. Equilibrium quotients K calculated from the externally referenced data for each of the 4 different protons were essentially the same. This gives evidence that the system behaves in accord with the pure 1:1 complex model and does not demand the assumption of simultaneous occurence of higher complexes. The values for K (= .115 l/mol), for the 4 apparent complex shifts (Icpt/K) and for the 4 nuclei specific AUS coefficients a 2 [1, 8] could be confirmed and somewhat improved by a Creswell-Allred processing of the data including AUS correction.

The failure of the AUS correction in producing parallel Scatchard plots from internally referenced shifts is caused by the nonlinear floating with the donor concentration of the internal reference signal. The cause of this nonlinear behaviour is analyzed, and arguments are presented that it can be prevented by use of reference substances with only one single reference group per molecule, i.e. the signal of such an internal reference must not have its origin in two or more equivalent nuclei groups within the reference molecule.
Pyridin-4-on-Nueleosid+: Stabilisierung der Struktur im Kristall und in wäßriger Lösung / Pyridine-4-on Nucleoside: Stabilisation of the Structure in the Crystal and in Aqueous Solution
Authors: Kaiser Peter M. , Nesper Reinhard , Tebbe Karl-Friedrich , Witzel Herbert
Published: February 2015

C10H13NO5 • H2O is monoclinic, space group P2i with a = 773.7 pm, b = 814.6 pm, c= 932.6 pm, β = 109.36° at 143 K, Z = 2. The crystal structure has been refined to R =0.031 with 1340 counter reflections. Features of this nucleoside include an orientation of the base at the glycosidic bond N(l)-C(l') in the anii-range (52.5°), a ribosyl moiety in the C(2')-endo(S) conformation and in contrast to many other nucleosides a trans arrange-ment at C(4')-C(5'). This unusual conformation is stabilized by a distinct H-bonding scheme including the water molecule and the oxygen of the adjacent pyridin-4-on ring system. NMR data indicate on the other side that in solution the conformation of the nucleoside is anti/g + similar to that of other pyrimidine nucleosides. The 5'-OH group replaces the water molecule in the crystal. The preferred anti position of the base cannot be explained by an interaction of H(2,6) of the base with the 5'-OH group or the C(4) oxygen. Both protons which couple with H(3,5) coalesce in a single sharp doublet. Water entropy seems to be the decisive factor for the stabilization of the anti/g+ conformation in aqueous solution.
Phosphoramides, XIX [1] Phosphorus Pentoxide Amine Hydrochloride Reagents in the Synthesis of 3-Amino-1,2-benzisothiazole-1,1-dioxides and 3-Aminothieno [3,4-d] isothiazole-1,1-dioxides
Authors: Jensen Klaus G. , Pedersen Erik B.
Published: February 2015

3-Amino-1,2-benzisothiazole-1,1-dioxides (2b-n) have been prepared by heating sac­charin (1) and the hydrochlorides of primary and secondary aliphatic amines with phos­phorus pentoxide and N,N-dimethylcyclohexylamine at 240 °C. 3-Aminothieno[3,4-d]-isothiazole-1,1-dioxides (6a-c) were similarly prepared from thieno[3,4-d]isothiazol- 3(2H)-one-1,1 -dioxide (6).

31P NMR spectra were obtained of reaction mixtures and reagents. Biological screening of 2 is discussed.
3,3-Dimethyl-4 [2-methyl-1-propenyl] -1,2-dioxetane: Its Thermal Stability and Chemiluminescent Properties
Authors: Adam Waldemar , Cueto Omar
Published: February 2015

The alkenyl-substituted 1,2-dioxetane (1) was prepared by photosensitized singlet oxygenation of 2,5-dimethyl-2,4-hexadiene and its activation and excitation parameters determined. It is shown that dioxetane (1) is comparable in its thermal stability to alkyl-substituted dioxetanes and an inefficient chemical source of electronic excitation.
Die Photoaddition von Bromtrichlormethan an Acroleindiethylacetal und die Synthese von 4.4.4-Trichlor-⊿2 -butenal / The Photoaddition of Bromotrichloromethane to Acroleindiethylacetal and the Synthesis of 4,4,4-Trichloro-2-butenal
Authors: Seidel Peter , Ugi Ivar
Published: February 2015

The preparation of 4,4,4-trichloro-⊿2 -butenal by photoaddition of bromotrichloro-methane to acroleindiethylacetal, subsequent elimination of hydrogen bromide by DBN, and then acidolysis of the acetal by TFA is described.
NOTIZEN: GaTeCl − Eine Tetraederschichtstruktur mit Ga−Te-Verknüpfung vom Typ des schwarzen Phosphors / GaTeCl − a Tetrahedral Layer Structure with Ga-Te Linking of the Black Phosphorus Type
Authors: Wilms Axel , Kniep Rüdiger
Published: February 2015

The crystal structure of GaTeCl contains layers consisting of GaTe3Cl tetrahedra which share common Te-vertices with six neighbouring equivalent tetrahedra; Cl-atoms are in terminal positions. The two-dimensional Ga-Te-framework is of an arrangement, which is also present in the structure of black phosphorus.
Kristallstruktur der stabilen Modifikation von SeCl4 / Crystal Structure of the Stable Modification of SeCl4
Authors: Kniep Rüdiger , Körte Lutz , Mootz Dietrich
Published: February 2015

Single crystals of the stable modification of selenium tetrachloride (α-SeCl4) were grown by sublimation, and the crystal structure was determined. As that of metastable β-SeCl4 it contains tetrameric cubane-like molecules Se4Cl4, but with different point symmetry and in positions which correspond to those of the atoms of the β-tungsten structure type.
K2PdP2 und K2PtAs2, zwei weitere Verbindungen mit MP2(As2)-Kettenstruktur / K2PdP2 and K2PtAs2, two Further Compounds with a MP2(As2)-Chain-Structure
Authors: Rózsa Sándor , Schuster Hans-Uwe
Published: February 2015

K2PdP2 and K2PtAs2 were prepared from the elements. They are isotypic with K2PdAs2 [1] and crystallize orthorhombically, space group Cmcm, with the following constants:

K2PdP2: a = 635.5 pm, b= 1389.8 pm, c = 590.0 pm.

K2PtAs2 :a = 646.5 pm, b= 1410.6 pm, c = 609.6 pm.
Eine Untersuchung über die Energie-Übertragung bei der triplett-sensibilisierten Photo-Isomerisierung der 6-endo- und 6-exo-alkylsubstituierten Tetramethylhomofulvene / An Energy Transfer Study of the Triplet Sensitized Photo-Isomerizations of 6-endo- and 6-exo-Alkyl-Substituted Tetramethylhomofulvenes
Authors: Brune Hans Albert , Lach Peter
Published: February 2015

The isomerizations following triplet sensitized excitations of three diastereomeric pairs of 6-endo-and 6-exo-alkyl substituted 1,2,3,5-Tetramethyl-4-methylenebicyclo[3.1.0]hex-2-enes have been studied with respect to the influence of the steric conditions during triplet energy transfer on the equilibrium constant of the photo-stationary equilibrium.
Aliphatische Flüssigkristalle, IV [1] Synthese einiger 1-(1,3-Dioxan-2- und -5-yl)piperidine / Aliphatic Liquid Crystals, IV [1] Synthesis of Some 1-(1.3-Dioxan-2- and -5-yl)Piperidines
Authors: Sucrow Wolfgang , Lüschen Ronald , Risse Annette
Published: February 2015

b , 2

The preparation of the title compounds 1and 12 is described. Their configurations are deduced from the NMR spectra. trans-4-Pentyl-1-(trans-2-pentyl-1,3-dioxan-5-yl)piperidine (2) exhibits a broad smectic B phase.
Stoffwechselprodukte von Mikroorganismen, XXIX [1] 13C-NMR-Spektren hochsubstituierter Naturstoffe vom Phthalid-Typ / Investigations on Metabolites of Microorganisms, XXIX [1] 13C NMR Spectra of Highly Substituted Natural Products of the Phthalide Type
Authors: Achenbach Hans , Mühlenfeld Andreas , Hunkler Dieter
Published: February 2015

Since the usual 13C shift increments are not applicable for very highly substituted benzenes, the 13C NMR spectra of 3-O-ethyl-cyclopolic acid (1) and 2 were studied and fully analyzed. These results were essential for the structure elucidation of a number of new highly substituted phthalides recently isolated from cultures of Aspergillus duricaulis [3].
Formamidinhim-Hexachloroferrat(III) Synthese und Kristallstruktur / Formamidinium-Hexachloroferrate(III) Synthesis and Crystal Structure
Authors: Demant Udo , Conradi Elke , Müller Ulrich , Dehnicke Kurt
Published: February 2015

[HC(NH2)2]3FeCl6 was obtained together with other products from the reaction of S4N4 with HCl in H2CCl2 in the presence of FeCl3. Its crystal structure was determined from X-ray diffraction data (473 independent observed reflexions, R = 0.047). Lattice constants: a = 961.6, c = 876.4 pm; tetragonal, space group P42/m, Z = 2. Of the two crystallographically independent formamidinium ions HC(NH2)2
⊕, one exhibits positional disorder; the other one has C-N bond lengths of 128 pm. The FeCl6
3⊖ ions have symmetry C2h, but the deviation from Oh is small.
Regulation of Postsynaptic Function by the Dementia-Related ESCRT-III Subunit CHMP2B
Authors: Chassefeyre Romain , Martínez-Hernández José , Bertaso Federica , Bouquier Nathalie , Blot Béatrice , Laporte Marine , Fraboulet Sandrine , Couté Yohann , Devoy Anny , Isaacs Adrian M. , Pernet-Gallay Karin , Sadoul Rémy , Fagni Laurent , Goldberg Yves
Published: February 2015

The charged multivesicular body proteins (Chmp1–7) are an evolutionarily conserved family of cytosolic proteins that transiently assembles into helical polymers that change the curvature of cellular membrane domains. Mutations in human CHMP2B cause frontotemporal dementia, suggesting that this protein may normally control some neuron-specific process. Here, we examined the function, localization, and interactions of neuronal Chmp2b. The protein was highly expressed in mouse brain and could be readily detected in neuronal dendrites and spines. Depletion of endogenous Chmp2b reduced dendritic branching of cultured hippocampal neurons, decreased excitatory synapse densityin vitroandin vivo, and abolished activity-induced spine enlargement and synaptic potentiation. To understand the synaptic effects of Chmp2b, we determined its ultrastructural distribution by quantitative immuno-electron microscopy and its biochemical interactions by coimmunoprecipitation and mass spectrometry. In the hippocampusin situ, a subset of neuronal Chmp2b was shown to concentrate beneath the perisynaptic membrane of dendritic spines. In synaptoneurosome lysates, Chmp2b was stably bound to a large complex containing other members of the Chmp family, as well as postsynaptic scaffolds. The supramolecular Chmp assembly detected here corresponds to a stable form of the endosomal sorting complex required for transport-III (ESCRT-III), a ubiquitous cytoplasmic protein complex known to play a central role in remodeling of lipid membranes. We conclude that Chmp2b-containing ESCRT-III complexes are also present at dendritic spines, where they regulate synaptic plasticity. We propose that synaptic ESCRT-III filaments may function as a novel element of the submembrane cytoskeleton of spines.
Microglial Activation Enhances Associative Taste Memory through Purinergic Modulation of Glutamatergic Neurotransmission
Authors: Delpech Jean-Christophe , Saucisse Nicolas , Parkes Shauna L. , Lacabanne Chloe , Aubert Agnes , Casenave Fabrice , Coutureau Etienne , Sans Nathalie , Layé Sophie , Ferreira Guillaume , Nadjar Agnes
Published: February 2015

The cerebral innate immune system is able to modulate brain functioning and cognitive processes. During activation of the cerebral innate immune system, inflammatory factors produced by microglia, such as cytokines and adenosine triphosphate (ATP), have been directly linked to modulation of glutamatergic system on one hand and learning and memory functions on the other hand. However, the cellular mechanisms by which microglial activation modulates cognitive processes are still unclear. Here, we used taste memory tasks, highly dependent on glutamatergic transmission in the insular cortex, to investigate the behavioral and cellular impacts of an inflammation restricted to this cortical area in rats. We first show that intrainsular infusion of the endotoxin lipopolysaccharide induces a local inflammation and increases glutamatergic AMPA, but not NMDA, receptor expression at the synaptic level. This cortical inflammation also enhances associative, but not incidental, taste memory through increase of glutamatergic AMPA receptor trafficking. Moreover, we demonstrate that ATP, but not proinflammatory cytokines, is responsible for inflammation-induced enhancement of both associative taste memory and AMPA receptor expression in insular cortex. In conclusion, we propose that inflammation restricted to the insular cortex enhances associative taste memory through a purinergic-dependent increase of glutamatergic AMPA receptor expression at the synapse.
Economic Choices Reveal Probability Distortion in Macaque Monkeys
Authors: Stauffer William R. , Lak Armin , Bossaerts Peter , Schultz Wolfram
Published: February 2015

Economic choices are largely determined by two principal elements, reward value (utility) and probability. Although nonlinear utility functions have been acknowledged for centuries, nonlinear probability weighting (probability distortion) was only recently recognized as a ubiquitous aspect of real-world choice behavior. Even when outcome probabilities are known and acknowledged, human decision makers often overweight low probability outcomes and underweight high probability outcomes. Whereas recent studies measured utility functions and their corresponding neural correlates in monkeys, it is not known whether monkeys distort probability in a manner similar to humans. Therefore, we investigated economic choices in macaque monkeys for evidence of probability distortion. We trained two monkeys to predict reward from probabilistic gambles with constant outcome values (0.5 ml or nothing). The probability of winning was conveyed using explicit visual cues (sector stimuli). Choices between the gambles revealed that the monkeys used the explicit probability information to make meaningful decisions. Using these cues, we measured probability distortion from choices between the gambles and safe rewards. Parametric modeling of the choices revealed classic probability weighting functions with inverted-S shape. Therefore, the animals overweighted low probability rewards and underweighted high probability rewards. Empirical investigation of the behavior verified that the choices were best explained by a combination of nonlinear value and nonlinear probability distortion. Together, these results suggest that probability distortion may reflect evolutionarily preserved neuronal processing.