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  • 101.
    Bergstrom, M
    et al.
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Juhlin, C
    Department of Surgical Sciences.
    Bonasera, TA
    Sundin, A
    Uppsala University, Medicinska vetenskapsområdet, Faculty of Medicine, Department of Oncology, Radiology and Clinical Immunology.
    Rastad, J
    Department of Surgical Sciences.
    Åkerström, Göran
    Department of Surgical Sciences.
    Langstrom, B
    Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    PET imaging of adrenal cortical tumors with the 11beta-hydroxylase tracer11C-metomidate.2000In: J Nucl Med, Vol. 41, p. 275-Article in journal (Refereed)
  • 102.
    Bergström, M.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Awad, R.
    Estrada, S., Malman, J.
    Lu, L., Lendvai, G.
    Bergström-Pettermann, E., Långström, B.
    Autoradiography with positron emitting isotopes in positron emission tomography tracer discovery2003In: Mol Imaging Biol., Vol. 6, no 460, p. 390-396Article in journal (Refereed)
  • 103. Bergström, M.
    et al.
    Fasth, K-J.
    Kilpatrick, G.
    Ward, P.
    Cable, K M.
    Wipperman, M D.
    Sutherland, D R.
    Långström, B.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Brain uptake and receptor binding of two (11C)labelled selective high affinity NK1-antagonists, GR203040 and GR205171 - PET studies in rhesus monkey.2000In: Neuropharmacology, ISSN 0028-3908, Vol. 39, no 4, p. 664-670Article in journal (Refereed)
  • 104. Bergström, Mats
    et al.
    Muhr, Carin
    Lundberg, Per-Ola
    Bergström, Kjell
    Lundkvist, Hans
    Antoni, Gunnar
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Fasth, Karl-Johan
    Långström, Bengt
    Amino acids distribution and metabolism in pituitary adenomas using positron emission  tomography with 11C-L- and D-methionine.1987In: Journal of computer assisted tomography, ISSN 0363-8715, E-ISSN 1532-3145, Vol. 11, p. 384-389Article in journal (Refereed)
  • 105.
    Bergström, Sara
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Analytisk kemi.
    Development of Integrated Micro-Analytical Systems2003Licentiate thesis, monograph (Other scientific)
  • 106.
    Bergström, S.K.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Samskog, J.
    Markides, K.E.
    Development of a Poly(dimethylsiloxane) Interface for On-Line Capillary Column Liquid Chromatography-Capillary Electrophoresis Coupled to Sheathless Electrospray Ionization Time-of-Flight Mass Spectrometry2003In: Anal. Chem., no 75, p. 5461-5467Article in journal (Refereed)
  • 107.
    Bergström, Örjan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Lithium-ion insertion in a V6O13 cathode1998Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The transition metal oxide V6O13 is a promising cathode material for high-capacity lithium-polymer batteries in conjunction with a lithium-metal anode. The electro-chemical behaviour of V6O13 has its origin in the ability of the vanadium ions to change their-oxidation states, combined with the open nature of its crystal structure which allows lithium ions to diffuse through it. When incorporated into the cathode, the material passes through a series of lithiated phases as the battery is discharged. Inthis thesis, structure-property relationships of these lithiated phases have been studied. The techniques used have been in situ X-ray powder diffraction and single-crystal X-ray diffraction on electrochemically lithiated samples, in combination with electrochemical cycling.

    Five different lithiated phases were identified : LixV6O13 for x = 0.5, 1.0, 2.0, 3.0 and 6.0 at potentials 2.78, 2.68, 2.52, 2.45 and 2.00V vs. Li/Li+, respectively. The structures of the x = 0, 2.0 and 3.0 phases have been investigated using single-crystal techniques; deformation electron density refinement has been performed for the x=0 and 2.0 phases. The reduction (from V5+ to V4+) of one of the threeindependent vanadium atoms (V2) in the asymmetric unit can be identified with some degree of certainty as Li2V6O13 is formed. On this basis, a proposal is made for the complete sequence of vanadium oxidation-state changes for the entire lithium insertion process.

  • 108.
    Berlin, S
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Engman, L
    A radical cyclization route to pyrrolidines based on conjugate addition to electron deficient phenylselenenylalkenes2000In: TETRAHEDRON LETTERS, ISSN 0040-4039, Vol. 41, no 19, p. 3701-3704Article in journal (Refereed)
    Abstract [en]

    alpha-Phenylselenenyl-alpha,beta-unsaturated esters, amides, ketones, nitriles and sulfones were prepared by zinc chloride promoted chloroselenation/dehydrochlorination of the corresponding alpha,beta-unsaturated compounds. After Michael addition of allyl

  • 109.
    Berlin, S.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Ericsson, C
    Engman, L
    Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization2002Article in journal (Other scientific)
  • 110.
    Berlin, S
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Ericsson, C
    Engman, L.
    Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin-3-ones2003In: J. Org. Chem., no 68, p. 8386-Article in journal (Refereed)
  • 111.
    Berlin, Stefan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Construction of Five-Membered Heterocycles via Radical Cyclization2001Licentiate thesis, monograph (Other scientific)
  • 112.
    Berlin, Stefan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Construction of Five-Membered Heterocyclic Compounds via Radical Cyclization2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis describes how radical cyclization chemistry can be applied for the construction of heterocyclic compounds.

    In the first part, a series of electron deficient α-phenylselenenylalkenes were prepared via a PhSeCl-addition/HCl-elimination sequence. Allyl- and propargylamines readily underwent conjugate addition to these species to produce pyrrolidines or dihydropyrrol derivatives, after triethylborane initiated reductive radical cyclization in the presence of tris(trimethylsilyl)silane.

    The second part describes a convergent synthesis of the pineal hormone melatonin. The indole nucleus is secured via a tris(trimethylsilyl)silane mediated 5-exo radical cyclization. The protocol provides convenient and simple access to compounds useful for studies of biological activity and structure activity relationships.

    The third part describes construction of substituted tetrahydrofuran-3-ones and pyrrolidin-3-ones. Regioselective ring-opening of epoxides or aziridines with benzeneselenolate/tellurolate, followed by Michael addition to electron deficient alkynes afforded the corresponding O/N-vinylated compounds. The tetrahydrofuran-3-ones and pyrrolidin-3-ones were secured via radical carbonylation/reductive cyclization using pressurized carbon monoxide (80 atm).

    The fourth part is concerned with the effect of an N-protecting group on the cyclization of 2-substituted-3-aza-5-hexenyl radicals. Relative energies for reactants and transition states were determined using density functional calculations. Reactant and transition state conformers leading to cis-product were lower in energy than those leading to trans-product. The results can be explained by the unfavorable 1,2-strain present in chair-equatorial and boat-equatorial conformers.

    List of papers
    1. A Radical Cyclization Route to Pyrrolidines Based on Conjugate Addition to Electron Deficient Phenylselenenylalkenes
    Open this publication in new window or tab >>A Radical Cyclization Route to Pyrrolidines Based on Conjugate Addition to Electron Deficient Phenylselenenylalkenes
    2000 In: Tetrahedron Letters, Vol. 41, no 19, p. 3701-3704Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90418 (URN)
    Available from: 2003-05-12 Created: 2003-05-12Bibliographically approved
    2. Efficient Route to the Pineal Hormone Melatonin by Radical-Based Indole Synthesis
    Open this publication in new window or tab >>Efficient Route to the Pineal Hormone Melatonin by Radical-Based Indole Synthesis
    2003 (English)In: Synthetic Communications, ISSN 0039-7911, E-ISSN 1532-2432, Vol. 33, no 20, p. 3631-3641Article in journal (Refereed) Published
    Abstract [en]

    The hormone melatonin, which is known to have a range of important biological effects, has been prepared in a high-yielding route that features formation of the indole nucleus by radical cyclization. Mediation of the radical cyclization by tristrimethylsilylsilane (TTMSS) is more efficient than by N-ethylpiperidine hypophosphite.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-90419 (URN)10.1081/SCC-120024751 (DOI)
    Available from: 2003-05-12 Created: 2003-05-12 Last updated: 2017-12-14Bibliographically approved
    3. Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization
    Open this publication in new window or tab >>Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization
    2002 In: Organic Letters, Vol. 4, p. 3-6Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-90420 (URN)
    Available from: 2003-05-12 Created: 2003-05-12Bibliographically approved
    4. Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin3-0nes
    Open this publication in new window or tab >>Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin3-0nes
    In: Journal of Organic ChemistryArticle in journal (Refereed) Submitted
    Identifiers
    urn:nbn:se:uu:diva-90421 (URN)
    Available from: 2003-05-12 Created: 2003-05-12Bibliographically approved
    5. On the origin of cis selectivity in the cyclization of N-protected 2-substituted 3-aza-5-hexenyl radicals: a density functional study
    Open this publication in new window or tab >>On the origin of cis selectivity in the cyclization of N-protected 2-substituted 3-aza-5-hexenyl radicals: a density functional study
    Show others...
    2004 (English)In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 69, no 5, p. 1487-1491Article in journal (Refereed) Published
    Abstract [en]

    Cyclization of the N-dimethylphosphinoyl-2-methyl-3-aza-5-hexenyl radical has been studied at the UB3LYP/6-31+G(d)//UB3LYP/6-31G(d) hybrid density functional level. The corresponding radical precursor has been synthesized and found to give cis/trans ratios of up to 10/1 in reductive radical cyclizations. The relative energies of reactant and transition state conformers were determined. In discord with the Beckwith-Houk model, it has been found that chair-axial transition states, which lead to cis products, are lowest in energy, rationalizing the observed experimental diastereoselectivity.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-90422 (URN)10.1021/jo030294h (DOI)14987001 (PubMedID)
    Available from: 2003-05-12 Created: 2003-05-12 Last updated: 2017-12-14Bibliographically approved
  • 113.
    Berlin, Stefan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Construction of Tetrahydrofuran-3-ones from Readily Available Organochalcogen Precursors via Radical Carbonylation/Reductive Cyclization2002In: Organic Letters, Vol. 4, p. 3-6Article in journal (Refereed)
  • 114.
    Berlin, Stefan
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Radical Carbonylation/Reductive Cyclization for the Construction of Tetrahydrofuran-3-ones and Pyrrolidin3-0nesIn: Journal of Organic ChemistryArticle in journal (Refereed)
  • 115.
    Berlin, Stefan
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Engman, Lars
    A Radical Cyclization Route to Pyrrolidines Based on Conjugate Addition to Electron Deficient Phenylselenenylalkenes2000In: Tetrahedron Letters, Vol. 41, no 19, p. 3701-3704Article in journal (Refereed)
  • 116. Bertilsson, S. K.
    et al.
    Ekegren, J. K.
    Modin, S. A.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Andersson, P. G.
    The aza-Diels-Alder reaction protocol - a useful approach to chiral, sterically constrained alpha-amino acid derivatives2001In: Tetrahedron, ISSN 0040-4020, Vol. 57, no 30, p. 6399-6406Article in journal (Refereed)
  • 117.
    Bertilsson, SK
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Andersson, PG
    A rigid dirhodium(II) carboxylate as an efficient catalyst for the asymmetric cyclopropanation of olefins2000In: JOURNAL OF ORGANOMETALLIC CHEMISTRY, ISSN 0022-328X, Vol. 603, no 1, p. 13-17Article in journal (Refereed)
    Abstract [en]

    The dirhodium(II) complex 7 of (1S,3R,4R)-2-(p-tert-butylphenylsulphonyl)-2-aza-bicycol[2.2.1]heptane-3-carboxylic acid (3) (or its enantiomer) was synthesised in four steps from cyclopentadiene, (R)- or (S)-phenylethylamine and methyl glyoxylate. Complex

  • 118.
    Bertilsson, SK
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Ekegren, JK
    Modin, SA
    Andersson, PG
    The aza-Diels-Alder reaction protocol - a useful approach to chiral, sterically constrained alpha-amino acid derivatives2001In: TETRAHEDRON, ISSN 0040-4020, Vol. 57, no 30, p. 6399-6406Article in journal (Refereed)
    Abstract [en]

    Different types of polycyclic alpha -amino acid derivatives are prepared from chiral imines by using well-established aza-Diels-Alder reaction conditions. Simply by varying the diene moiety, different products such as spirocyclic compounds 8 and 9, anthra

  • 119.
    Bertilsson, Sophie
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Asymmetric Formation and Isomerization of Three-Membered Rings: Catalyst Development and Evaluation2001Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Enantiopure α-amino acid derivatives were prepared using a protocol which allows for highly controlled regio- and chemoselectivity in the hydrogenation/ hydrogenolysis of aza-Diels-Alder adducts. One of the resulting α-amino esters, (1S,3R,4R)-2-azabicyclo[2.2.1]heptane-3-carboxylic acid ethyl ester, was utilized further as a catalyst precursor.

    Significant improvements were achieved in the asymmetric lithium amide-mediated epoxide rearrangement reaction. An efficient catalytic system was developed, based on 5 mol% of (1S,3R,4R)-3-(amino)methyl-2-azabicyclo[2.2.1]heptanes and stoichiometric amounts of lithium diisopropylamide (LDA). With pyrrolidine or (2R,5R)-dimethylpyrrolidine as the amine moiety, the isomerization into allylic alcohols was accomplished for 5–7-membered cycloalkene oxides and (Z)-octene oxide with yields of >90% and enantioselectivities up to 99% ee. The studies indicate that the active catalyst species is a monomer, which is in equilibrium with inactive aggregates. The addition of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) led to a reaction rate acceleration. In the catalytic reaction, where there is a competing LDA-mediated rearrangement, the presence of DBU also improved the enantioselectivity.

    Furthermore, the asymmetric addition of carbenes and nitrenes to olefins was investigated. N,N'- and N,O-oxazolines were evaluated as ligands in the Cu-catalyzed aziridination of alkenes. Two of the oxazolines formed highly active catalysts (90% yield). However, the enantioselectivity was moderate (≤34% ee). Another catalyst, tetrakis-[(1S,3R,4R)-2-(p-tert-butylbenzene)sulphonyl-2-azabicyclo[2.2.1]heptane-3-carboxylate]dirhodium(II) was prepared and successfully applied in the reaction of styrenes and cyclic enol ethers with phenyl- and vinyldiazoacetates, affording cyclopropanes in up to 95% yield and 92% ee. In contrast to earlier observations, the best results were obtained with electron-rich olefins.

  • 120.
    Bertilsson, Sophie
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Asymmetric base-promoted epoxide rearrangement: achiral lithium amides revisited2002In: Tetrahedron, no 58, p. 4665-4668Article in journal (Refereed)
  • 121.
    Bertilsson, Sophie
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Södergren, Mikael
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    New Catalysts for the Base-Promoted Isomerization of Epoxides to Allylic Alcohols. Broadened Scope and Near-Perfect Asymmetric Induction2002In: J. Org. Chem., no 67, p. 1567-1573Article in journal (Refereed)
  • 122.
    Bertilsson, Sophie
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Tedenborg, Lars
    Alonso, Diego
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Chiral N, N' - and N,O-Bidentate Anionic Ligands. Preparation, Metal Complexation, and Evalution in the Asymmetric Aziridination of Olefins1999In: Organometallics, no 18, p. 1281-1286Article in journal (Refereed)
  • 123.
    Besev M, Engman L,
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Diastereocontrol by Hydroxyl Auxiliary in the Synthesis of Pyrrolidines via Radical Cyclization2002In: Org. Lett., no 4, p. 3023-Article in journal (Other scientific)
  • 124.
    Besev, M
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Engman, L
    Pyrrolidines from beta-aminoselenides via radical cyclization. Diastereoselectivity control by the N-substituent2000In: ORGANIC LETTERS, ISSN 1523-7060, Vol. 2, no 11, p. 1589-1592Article in journal (Refereed)
    Abstract [en]

    [GRAPHICS] N-Allyl-beta-aminoalkyl phenyl selenides-precursors of 3-aza-5-hexenyl radicals-were prepared by ring opening of N-allylaziridines with benzeneselenol under acidic conditions or by sodium cyanoborohydride reduction of N-allylimines of alpha-phe

  • 125.
    Besev, Magnus
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Pyrrolidines via Radical Cyclization2000Licentiate thesis, monograph (Other scientific)
  • 126. Bischof, Gerhard
    et al.
    Silbernagl, Alexander
    Hermansson, Kersti
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Probst, Michael
    Quantum chemical study of the molecular dynamics of hydrated Li+ and Be2+ cations1997In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 65, no 5, p. 803-816Article in journal (Refereed)
    Abstract [en]

    Molecular dynamics simulations of clusters of Li+ and Be2(+) cations with up to 12 water molecules were performed calculating the particle trajectories using Hartree-Fock-derived forces. It was found that independent of the starting configuration tetrahedral clusters are obtained in less than 1 ps. Only for Li+ clusters, transition states with five and three water molecules are found. We discuss the structures of the clusters and the vibrational dynamics of the water molecules and compare them with other ab initio simulations, with simulations using analytical potential functions, and with static calculations. Water-dissociation (hydrogen transfer) reactions which take place at elevated temperatures were investigated. (C) 1997 John Wiley & Sons, Inc.

  • 127.
    Bjorefors, F
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Gadomska, J
    Donten, M
    Nyholm, L
    Stojek, Z
    Influence of mixed diffusional, migrational, and convective mass transport on the response of a wall-tube microelectrode in a flow injection system1999In: ANALYTICAL CHEMISTRY, ISSN 0003-2700, Vol. 71, no 21, p. 4926-4931Article in journal (Refereed)
    Abstract [en]

    The current response of a 10-mu m walt-tube microelectrode in a now injection system under the conditions of low ionic strength has been examined experimentally for several redox systems such as ferrocene in methanol, undiluted methanol, and water in ace

  • 128.
    Bjorefors, F
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Nyholm, L
    Stripping voltammetry at preplated mercury coated microelectrodes in flowing solutions1996In: ANALYTICA CHIMICA ACTA, ISSN 0003-2670, Vol. 325, no 1-2, p. 11-24Article in journal (Refereed)
    Abstract [en]

    A flow system is described in which stable preplated mercury coatings on microelectrodes can be obtained due to minimised handling of the electrode and the fact that potentiostatic control can be maintained also between the experiments. Compared to the d

  • 129.
    Bjorefors, F
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Nyholm, L
    Donten, M
    Stojek, Z
    Amperometric determination of the water content in acetone, butter and margarine using a wall-tube platinum microelectrode in a flow injection system1999In: ANALYST, ISSN 0003-2654, Vol. 124, no 2, p. 143-146Article in journal (Refereed)
    Abstract [en]

    Amperometric determinations of the water content in acetone, butter and margarine were performed using a wall-tube platinum microelectrode in combination with a flow injection system. For the butter and margarine samples, acetone containing small amounts

  • 130.
    Björefors, Fredrik
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Fundamental investigations and applications of microelectrode based detections in flowing solutions1999Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The influence of diffusional, migrational and convective mass transport at microelectrodes employed for voltammetric and amperometric detection in flowing solutions has been investigated. Special attention was paid to the influence of convection on the IR drop in organic solvents and on the transport of reaction products between individual electrode bands of microarray electrodes. A flow injection system was also designed to study the stability of mercury films coated on microelectrodes for the purpose of stripping analysis.

    Increased influence of convection, obtained by altering the flow rate or by changing the position of the microelectrode in a wall-tube flow cell, at low support ratios in organic solvents was found to result in decreased currents as a consequence of the inability to maintain a sufficient amount of ions at the vicinity of the microelectrode surface. Successful determinations of the water content in butter and margarine could be performed in an acetone based flow injection system, provided that the detection potential was chosen to accommodate the different support ratios in the injected solutions.

    The degree of redox cycling at interdigitated microarray electrodes was found to increase if the flow rate was reduced from 20 to 2 µl/min. Even at these low flow rates, the degree of redox cycling in stationary solutions was, however, always larger compared to the values obtained under the influence of convection. A microarray electrode was also employed to improve the selectivity in the detection of poorly separated species in capillary electrophoresis.

    By employing a flow injection system, it was found that the stability of mercury films plated on platinum and carbon fibre microelectrodes could be improved as potential control could be maintained during solution exchange and between individual experiments. Stripping voltammetric determinations of nickel at nM concentrations and of copper in a low ionic strength solution was demonstrated in the flow injection system.

  • 131. Björkman, M.
    et al.
    Doi, H.
    Resul, B.
    Suzuki, M.
    Noyori, R.
    Watanabe, Y.
    Långström, B.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Synthesis of a 11C-labelled prostaglandin F2-alfa analogue using an improved method for Stille reactions with (11C)methyl iodide2000In: J.Labelled Compd. Radiopharm., ISSN 0362-4803, Vol. 43, no 14, p. 1327-1334Article in journal (Refereed)
  • 132. Björkman, M.
    et al.
    Långström, B
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Functionalization of 11C-labeled olefins via a Heck couplin reaction.2000In: Journal of the Chemical Society-Perkin Transactions, ISSN 1470-4358, Vol. 1, no 18, p. 3031-34Article in journal (Other scientific)
  • 133.
    Björkman, Margareta
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Palladium-promoted synthesis of compounds labelled with ¹¹C: Synthesis of ¹¹C-labelled prostacyclin and prostaglandin analogues2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Palladium-promoted reactions have been employed for the synthesis of compounds labelled with 11C (t½ = 20.3 min). The precursor [11C]methyl iodide was used in palladium-promoted cross-coupling reactions with organostannanes. With this method, large molecules with several functional groups, that is prostacyclin analogues, have been synthesised in up to 54 % decay-corrected radiochemical yield, calculated from [11C]methyl iodide. However, since this method did not afford reproducible yields, a second method where copper(I) was used as a co-catalyst with palladium, was developed. In the second method, a lower reaction temperature could be used and more reproducible yields were obtained. Employing this method, a prostaglandin analogue was synthesised in 34 % decay-corrected radiochemical yield calculated from [11C]methyl iodide. The total synthesis time was 30 min and the radiochemical purity was higher than 95 %. The specific radioactivity of the compounds obtained with these two methods was approximately 100 GBq/μmol.

    11C-Labelled aliphatic and aromatic alkenes were synthesised from [11C]methyl iodide in a Wittig olefination reaction using a published method. The 11C-labelled alkenes were reacted with five aromatic halidein Heck coupling reactions, producing five [11C]stilbene analogues in 34-40 % decay-corrected radiochemical yield. The radiochemical purity was higher than 95 % and the total synthesis timwas 40 min.

    11C-Labelled alkenes were also synthesised from 11C-labelled aldehydes. The 11C-labelled aldehydes were obtained from [11C]carbon monoxide in a palladium-mediated formylation of aryl iodides in 51-87 % radiochemical yield, determined by analytical LC and corrected for trappinefficiency. A range of palladium catalysts and hydride reagents were investigated. The labelled aldehydes were used in a subsequent Wittig olefination reaction where various Wittig salts were employed tsynthesise a variety of alkenes. The radiochemical yields were 30-76 %, determined by analytical LC.

  • 134.
    Blomquist, G.
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Engler, H.
    Wall, A.
    Sandell, J.
    Koivisto, P.
    Långström, B.
    Reference tissue methods in analyzing brain uptake of PIB with PET2003In: EANM, Amsterdam, 2003Conference paper (Other scientific)
  • 135.
    Bohl E, Carlsson J, Edwards K, Sjöberg S, Gedda L
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    SLT-particles for twostep targeting in boron neutron capture therapy2001In: Frontiers in neutron capture therapy, p. 1069-1075Article in journal (Other scientific)
  • 136.
    Bohl Kullberg E, Carlsson J, Edwards K, Capala J, Sjöberg S, Gedda L.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Introductory Experiments On Ligand Liposomes as Delivery Agents for Boron Neutron Capture Therapy2003In: International Journal of Oncology, no 23, p. 461-467Article in journal (Other scientific)
  • 137.
    Bonasera T., Grue-Sorensen G., Ortu G., Binderup E., Bergström M., Björkling F., Långström B.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    The Synthesis of [26,27-11C]dihydroxyvitam in D3, a tracer for positron emission tomography (PET)2001In: Bioorganic & Medical Chemistry, no 9(12), p. 3123-312Article in journal (Refereed)
  • 138.
    Borbath, I
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Gregoire, V
    Bergström, M
    Laryea, D
    Långström, B
    P.S,
    Use of 5-[(76)Br]bromo-2'-fluoro-2'.deoxyuridine as a ligand for tumour proliferation: validation in an animal tumour model2002In: Eur. J. Nucl. Med. Mol. Imaging, Vol. 1, no 29, p. 19-27Article in journal (Other scientific)
  • 139. Brandt, P
    et al.
    Andersson, P G
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Exploring the chemistry of 3-substituted 2-azanorbornyls in asymmetric catalysis.2000In: Synlett, ISSN 0936-5214, no 8, p. 1092-1106Article in journal (Other scientific)
  • 140.
    Brandt, P
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Andersson, P.G.
    A DFT Exploration of the Enantiolselective Rearrangement of Cyclohexene Oxide to Cyclohexenol2003In: Tetrahedron, no 59, p. 9695-Article in journal (Refereed)
  • 141.
    Brandt P, Hedberg C, Andersson P.G
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    New Mechanistic Insights into the Ir-(phosphano-oxazoline) Catalysed Hydrogenation of Unfunctinalized Olefines: A DFT and Kinetic Study2003In: Chem. Eur. J., no 9, p. 339-Article in journal (Other scientific)
  • 142. Brandt, Peter
    et al.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Exploring the Chemistry of 3-Substituted 2-Azanorbornyls in Asymmetric Catalysis2000In: Synlett, no 8, p. 1092-1106Article in journal (Refereed)
    Abstract
  • 143. Brandt, Peter
    et al.
    Hedberg, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    New Mechanistic Insights into the Iridium-Phosphanooxazoline-Catalyzed Hydrogenation of Unfunctionalized Olefins: A DFT and Kinetic Study2003In: Chem. Eur. J., no 9, p. 339-347Article in journal (Refereed)
    Abstract
  • 144. Brandt, Peter
    et al.
    Hedberg, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Andersson, Pher G.
    New Mechanistic Insights into the Iridium-Phosphanooxazoline Catalyzed Hydrogenation of Unfunctionalized Olefins: A DFT and Kinetic Study2003In: Chemistry-A European Journal, ISSN 0022-3263, Vol. 9, no 1, p. 339-347Article in journal (Refereed)
    Abstract
  • 145. Brandt, Peter
    et al.
    Hedberg, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Lawonn, Klaus
    Pinho, Pedro
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    A Theoretical and Experimental Study of the Asymmetric Addition of Dialkylzinc to N-(Diphenylphosphinoyl)benzalimine1999In: Chem. Eur. J., no 5, p. 1692-1699Article in journal (Refereed)
    Abstract
  • 146. Brandt, Peter
    et al.
    Hedberg, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry.
    Lawonn, Klaus
    Pinho, Pedro
    Andersson, Pher G.
    A Theoretical and Experimental Study of the Asymmetric Addition of Dialkylzinc to N-(diphenylphosphinoyl)benzalimine1999In: Chemistry-A European Journal, ISSN 0947-6539, Vol. 5, no 6, p. 1692-1699Article in journal (Refereed)
    Abstract
  • 147. Brandt, Peter
    et al.
    Roth, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Origin of Enantioselectivity in the Ru(arene)(amino alcohol)-Catalyzed Transfer Hydrogenation of Ketones2004In: J. Org. Chem., no 69, p. 4885-4890Article in journal (Refereed)
    Abstract
  • 148.
    Brandt, Peter
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Södergren, Mikael
    Andersson, Pher
    Department of Chemistry. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Norrby, Per-Ola
    Mechanistic Studies of Copper-Catalyzed Alkene Aziridination2000In: J. Am. Chem. Soc., ISSN 0002-7863, no 122, p. 8013-8020Article in journal (Refereed)
  • 149.
    Bratt K, Sunnerheim K, Bryngelsson S, Fagerlund A, Engman L, Andersson R.E, Dimberg L.H
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Avenanthramides in Oats (Avena sativa L.) and Structure-Antioxidant Activity Relationships2003In: J. Agric. Food Chem, no 51, p. 594-Article in journal (Other scientific)
  • 150.
    Bratt, K
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry.
    Sunnerheim, K
    Bryngelsson, S
    Fagerlund, A
    Engman, L
    Häll, Dimberg L.
    Avenanthramides in Oats: Structure - Antioxidant Activity Relationsip2003In: J. Agric Food Chem., no 51, p. 594-600Article in journal (Other scientific)
1234567 101 - 150 of 851
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