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  • 1.
    Bengtsson, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Nelander, Hanna
    Almqvist, Fredrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Asymmetric Synthesis of 2,4,5-Trisubstituted (2)-Thiazolines2013In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 19, no 30, p. 9916-9922Article in journal (Refereed)
    Abstract [en]

    (2)-Thiazolines are interesting heterocycles that display a wide variety of biological characteristics. They are also common in chiral ligands used for asymmetric syntheses and as synthetic intermediates. Herein, we present asymmetric routes to 2,4,5-trisubstituted (2)-thiazolines. These (2)-thiazolines were synthesized from readily accessible/commercially available ,-unsaturated methyl esters through a Sharpless asymmetric dihydroxylation and an ON acyl migration reaction as key steps. The final products were obtained in good yields with up to 97% enantiomeric excess.

  • 2.
    Berg, Lotta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Mishra, Brijesh Kumar
    Andersson, C. David
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Ekström, Fredrik
    Linusson, Anna
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    The Nature of Activated Non-classical Hydrogen Bonds: A Case Study on Acetylcholinesterase-Ligand Complexes2016In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 22, no 8, p. 2672-2681Article in journal (Refereed)
    Abstract [en]

    Molecular recognition events in biological systems are driven by non-covalent interactions between interacting species. Here, we have studied hydrogen bonds of the CHY type involving electron-deficient CH donors using dispersion-corrected density functional theory (DFT) calculations applied to acetylcholinesterase-ligand complexes. The strengths of CHY interactions activated by a proximal cation were considerably strong; comparable to or greater than those of classical hydrogen bonds. Significant differences in the energetic components compared to classical hydrogen bonds and non-activated CHY interactions were observed. Comparison between DFT and molecular mechanics calculations showed that common force fields could not reproduce the interaction energy values of the studied hydrogen bonds. The presented results highlight the importance of considering CHY interactions when analysing protein-ligand complexes, call for a review of current force fields, and opens up possibilities for the development of improved design tools for drug discovery.

  • 3.
    Chorell, Erik
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Pinkner, Jerome S
    Bengtsson, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Edvinsson, Sofie
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Cusumano, Corinne K
    Rosenbaum, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Johansson, Lennart B-Å
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hultgren, Scott J
    Almqvist, Fredrik
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Umeå University, Faculty of Medicine, Umeå Centre for Microbial Research (UCMR).
    Design and Synthesis of Fluorescent Pilicides and Curlicides: Bioactive Tools to Study Bacterial Virulence Mechanisms2012In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, no 15, p. 4522-4532Article in journal (Refereed)
    Abstract [en]

    Pilicides and curlicides are compounds that block the formation of the virulence factors pili and curli, respectively. To facilitate studies of the interaction between these compounds and the pili and curli assembly systems, fluorescent pilicides and curlicides have been synthesized. This was achieved by using a strategy based on structure-activity knowledge, in which key pilicide and curlicide substituents on the ring-fused dihydrothiazolo 2-pyridone central fragment were replaced by fluorophores. Several of the resulting fluorescent compounds had improved activities as measured in pili- and curli-dependent biofilm assays. We created fluorescent pilicides and curlicides by introducing coumarin and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) fluorophores at two positions on the peptidomimetic pilicide and curlicide central fragment. Fluorescence images of the uropathogenic Escherichia coli (UPEC) strain UTI89 grown in the presence of these compounds shows that the compounds are strongly associated with the bacteria with a heterogeneous distribution.

  • 4. Gustafson, Karl P. J.
    et al.
    Gorbe, Tamas
    de Gonzalo-Calvo, Gonzalo
    Yuan, Ning
    Schreiber, Cynthia L.
    Shchukarev, Andrey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Tai, Cheuk-Wai
    Persson, Ingmar
    Zou, Xiaodong
    Backvall, Jan-E.
    Chemoenzymatic Dynamic Kinetic Resolution of Primary Benzylic Amines using Pd-0-CalB CLEA as a Biohybrid Catalyst2019In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 25, no 39, p. 9174-9179Article in journal (Refereed)
    Abstract [en]

    Herein, we report on the use a biohybrid catalyst consisting of palladium nanoparticles immobilized on cross-linked enzyme aggregates of lipase B of Candida antarctica (CalB CLEA) for the dynamic kinetic resolution (DKR) of benzylic amines. A set of amines were demonstrated to undergo an efficient DKR and the recyclability of the catalysts was studied. Extensive efforts to further elucidate the structure of the catalyst are presented.

  • 5. Hawley, Andrew L.
    et al.
    Ohlin, C. André
    Umeå University, Faculty of Science and Technology, Department of Chemistry. School of Chemistry, Melbourne, Australia).
    Fohlmeister, Lea
    Stasch, Andreas
    Heavier Group 13 Metal(I) Heterocycles Stabilized by Sterically Demanding Diiminophosphinates: a Structurally Characterized Monomer–Dimer Pair For Gallium2017In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, no 2, p. 447-455Article in journal (Refereed)
    Abstract [en]

    We have synthesized and characterized the monomeric diiminophosphinate-stabilized Group 13 metal(I) complexes [DipLE:], DipL=Ph2P(NDip)2, Dip=2,6-iPr2C6H3; E=Ga (1), In (2) and Tl (3). In addition, we structurally characterized the dimeric complex [(DipLGa)2], 12. Similar synthetic attempts using MesL=Ph2P(NMes)2, Mes=2,4,6-Me3C6H2 afforded product mixtures from which the mixed oxidation state species [(MesL)3Ga4I3] 4 was isolated. [DipLGa:] 1 is converted with dry air to the gallium(III) oxide species [(DipLGaO)2] 5. Density Functional Theory studies on [DipLE:] and [(DipLE)2], E=Al−Tl, shed light on the bonding in these compounds and show that the newly formed E−E bonding interactions can be described as weak single σ-bond with no significant π-bonding contribution for E=Al, Ga. A large contribution to the dimer binding enthalpies results from London dispersion forces.

  • 6.
    Jamroskovic, Jan
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Livendahl, Madeleine
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Eriksson, Jonas
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Chorell, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Sabouri, Nasim
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Identification of Compounds that Selectively Stabilize Specific G-Quadruplex Structures by Using a Thioflavin T-Displacement Assay as a Tool2016In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 22, no 52, p. 18932-18943Article in journal (Refereed)
    Abstract [en]

    Small molecules are used in the G-quadruplex (G4) research field in vivo and in vitro, and there are increasing demands for ligands that selectively stabilize different G4 structures. Thioflavin T (ThT) emits an enhanced fluorescence signal when binding to G4 structures. Herein, we show that ThT can be competitively displaced by the binding of small molecules to G4 structures and develop a ThT-displacement high-throughput screening assay to find novel and selective G4-binding compounds. We screened approximately 28 000 compounds by using three different G4 structures and identified eight novel G4 binders. Analysis of the structural conformation and stability of the G4 structures in presence of these compounds demonstrated that the four compounds enhance the thermal stabilization of the structures without affecting their structural conformation. In addition, all four compounds also increased the G4-structure block of DNA synthesis by Taq DNA polymerase. Also, two of these compounds showed selectivity between certain Schizosaccharomyces pombe G4 structures, thus suggesting that these compounds or their analogues can be used as selective tools for G4 DNA studies.

  • 7. Johnson, Rene L.
    et al.
    Villa, Eric M.
    Ohlin, C. Andre
    Rustad, James R.
    Casey, William H.
    O-17 NMR and Computational Study of a Tetrasiliconiobate Ion, [H2+xSi4Nb16O56]((14-x)-)2011In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, no 34, p. 9359-9367Article in journal (Refereed)
    Abstract [en]

    Rates of oxygen-isotope exchange were measured in the tetrasiliconiobate ion [H2+xSi4Nb16O56]((14-x)-) to better understand how large oxide ions interact with water. The molecule has 19 nonequivalent oxygen sites and is sufficiently complex to evaluate hypotheses derived from our previous work on smaller clusters. We want to examine the extent to which individual oxygen atoms react independently with particular attention given to the order of protonation of the various oxygen sites as the pH decreases from 13 to 6. As in our previous work, we find that the set of oxygen sites reacts at rates that vary over approximately 104 across the molecule at 6 < pH < 13 but with similar pH dependencies. There is NMR evidence of an intra-or intermolecular reaction at pH similar to 7, where new peaks began to slowly form without losing the O-17 isotopic tag, and at pH <= 6 these new peaks formed rapidly. The oxygen atoms bonded to silicon atoms began to isotopically exchange at pH 9 and below. The 17O NMR peak positions also vary considerably with pH for some, but not all, nonequivalent oxygen sites. This variation could be only partly accounted by electronic calculations, which indicate that oxygen atoms should shift similarly upon protonation. Instead, we see that some sites change enormously with pH, whereas other, similarly coordinated oxygen atoms are less affected, suggesting that either some protons are exchanging so rapidly that the oxygen sites are seeing an averaged charge, or that counterions are modulating the effect of the coordinated protons.

  • 8. Knighton, Richard C.
    et al.
    Emerson-King, Jack
    Rourke, Jonathan P.
    Ohlin, C. André
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Chaplin, Adrian B.
    Solution, Solid-State, and Computational Analysis of Agostic Interactions in a Coherent Set of Low-Coordinate Rhodium(III) and Iridium(III) Complexes2018In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 24, no 19, p. 4927-4938Article in journal (Refereed)
    Abstract [en]

    A homologous family of low‐coordinate complexes of the formulation trans‐[M(2,2′‐biphenyl)(PR3)2][BArF4] (M=Rh, Ir; R=Ph, Cy, iPr, iBu) has been prepared and extensively structurally characterised. Enabled through a comprehensive set of solution phase (VT 1H and 31P NMR spectroscopy) and solid‐state (single crystal X‐ray diffraction) data, and analysis in silico (DFT‐based NBO and QTAIM analysis), the structural features of the constituent agostic interactions have been systematically interrogated. The combined data substantiates the adoption of stronger agostic interactions for the IrIII compared to RhIII complexes and, with respect to the phosphine ligands, in the order PiBu3>PCy3>PiPr3>PPh3. In addition to these structure–property relationships, the effect of crystal packing on the agostic interactions was investigated in the tricyclohexylphosphine complexes. Compression of the associated cations, through inclusion of a more bulky solvent molecule (1,2‐difluorobenzene vs. CH2Cl2) in the lattice or collection of data at very low temperature (25 vs. 150 K), lead to small but statistically significant shortening of the M−H−C distances.

  • 9. Li, Man-Bo
    et al.
    Posevins, Daniels
    Gustafson, Karl P. J.
    Tai, Cheuk-Wai
    Shchukarev, Andrey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Qiu, Youai
    Backvall, Jan-E.
    Diastereoselective Cyclobutenol Synthesis: A Heterogeneous Palladium-Catalyzed Oxidative Carbocyclization-Borylation of Enallenols2019In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 25, no 1, p. 210-215Article in journal (Refereed)
    Abstract [en]

    A highly selective and efficient oxidative carbocyclization/borylation of enallenols catalyzed by palladium immobilized on amino-functionalized siliceous mesocellular foam (Pd-AmP-MCF) was developed for diastereoselective cyclobutenol synthesis. The heterogeneous palladium catalyst can be recovered and recycled without any observed loss of activity or selectivity. The high diastereoselectivity of the reaction is proposed to originate from a directing effect of the enallenol hydroxyl group. Optically pure cyclobutenol synthesis was achieved by the heterogeneous strategy by using chiral enallenol obtained from kinetic resolution.

  • 10.
    Livendahl, Madeleine
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Jamroskovic, Jan
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Ivanova, Svetlana
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Demirel, Peter
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Sabouri, Nasim
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Chorell, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Design and Synthesis of 2,2'-Diindolylmethanes to Selectively Target Certain G-Quadruplex DNA Structures2016In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 22, no 37, p. 13004-13009Article in journal (Refereed)
    Abstract [en]

    G-quadruplex (G4) structures carry vital biological functions, and compounds that selectively target certain G4 structures have both therapeutic potential and value as research tools. Along this line, 2,2'-diindolylmethanes have been designed and synthesized in this work based on the condensation of 3,6- or 3,7-disubstituted indoles with aldehydes. The developed class of compounds efficiently stabilizes G4 structures without inducing conformational changes in such structures. Furthermore, the 2,2'-diindolylmethanes target certain G4 structures more efficiently than others and this G4 selectivity can be altered by chemical modifications of the compounds.

  • 11. Ohlin, C. Andre
    et al.
    Harley, Stephen J.
    McAlpin, J. Gregory
    Hocking, Rosalie K.
    Mercado, Brandon Q.
    Johnson, Rene L.
    Villa, Eric M.
    Fidler, Mary Kate
    Olmstead, Marilyn M.
    Spiccia, Leone
    Britt, R. David
    Casey, William H.
    Rates of Water Exchange for Two Cobalt(II) Heteropolyoxotungstate Compounds in Aqueous Solution2011In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, no 16, p. 4408-4417Article in journal (Refereed)
    Abstract [en]

    Polyoxometalate ions are used as ligands in water-oxidation processes related to solar energy production. An important step in these reactions is the association and dissociation of water from the catalytic sites, the rates of which are unknown. Here we report the exchange rates of water ligated to Co-II atoms in two polyoxotungstate sandwich molecules using the O-17-NMR-based Swift-Connick method. The compounds were the [Co-4(H2O)(2)(B-alpha-PW9O34)(2)](10-) and the larger alpha beta beta alpha-[Co-4(H2O)(2)(P2W15O56)(2)](16-) ions, each with two water molecules bound trans to one another in a Co-II sandwich between the tungstate ligands. The clusters, in both solid and solution state, were characterized by a range of methods, including NMR, EPR, FT-IR, UV-Vis, and EXAFS spectroscopy, ESI-MS, single-crystal Xray crystallography, and potentiometry. For [Co-4(H2O)(2)(B-alpha-PW9O34)(2)](10-) at pH 5.4, we estimate: k(298) = 1.5(5) +/- 0.3 x 10(6) s(-1), Delta H-not equal = 39.8 +/- 0.4 kJ mol(-1), Delta S-not equal = + 7.1 +/- 1.2 J mol(-1)K(-1) and Delta V-not equal = 5.6 +/- 1.6 cm(3)mol(-1). For the Wells-Dawson sandwich cluster (alpha beta beta alpha-[Co-4(H2O)(2)(P2W15O56)(2)](16-)) at pH 5.54, we find: k(298) = 1.6(2) +/- 0.3 x 10(6)s(-1), Delta H-not equal = 27.6 +/- 0.4 kJ mol(-1) Delta S-not equal = -33 +/- 1.3 J mol(-1)K(-1) and Delta V-not equal = 2.2 +/- 1.4 cm(3)mol(-1) at pH 5.2. The molecules are clearly stable and monospecific in slightly acidic solutions, but dissociate in strongly acidic solutions. This dissociation is detectable by EPR spectroscopy as S=3/2 Co-II species (such as the [Co(H2O)(6)](2+) monomer ion) and by the significant reduction of the Co-Co vector in the XAS spectra.

  • 12.
    Prasad, Bagineni
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Jamroskovic, Jan
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Bhowmik, Sudipta
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Department of Biophysics, Molecular Biology & Bioinformatics, University of Calcutta, Kolkata, India.
    Kumar, Rajendra
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Romell, Tajanena
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Sabouri, Nasim
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Chorell, Erik
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Flexible Versus Rigid G-Quadruplex DNA Ligands: Synthesis of Two Series of Bis-indole Derivatives and Comparison of Their Interactions with G-Quadruplex DNA2018In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 24, no 31, p. 7926-7938Article in journal (Refereed)
    Abstract [en]

    Small molecules that target G-quadruplex (G4) DNA structures are not only valuable to study G4 biology but also for their potential as therapeutics. This work centers around how different design features of small molecules can affect the interactions with G4 DNA structures, exemplified by the development of synthetic methods to bis-indole scaffolds. Our synthesized series of bis-indole scaffolds are structurally very similar but differ greatly in the flexibility of their core structures. The flexibility of the molecules proved to be an advantage compared to locking the compounds in the presumed bioactive G4 conformation. The flexible derivatives demonstrated similar or even improved G4 binding and stabilization in several orthogonal assays even though their entropic penalty of binding is higher. In addition, molecular dynamics simulations with the c-MYC G4 structure showed that the flexible compounds adapt better to the surrounding. This was reflected by an increased number of both stacking and polar interactions with both the residues in the G4 DNA structure and the DNA residues just upstream of the G4 structure.

  • 13. Saa, Laura
    et al.
    Virel, Ana
    Biofunctional Nanomaterials, CIC biomaGUNE, Parque Tecnologico de San Sebastian, Paseo Miramon 182, 20009 San Sebastian, Spain.
    Sanchez-Lopez, Jose
    Pavlov, Valery
    Analytical applications of enzymatic growth of quantum dots2010In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 16, no 21, p. 6187-6192Article in journal (Refereed)
    Abstract [en]

    We have developed an analytical assay to detect the enzymatic activity of acetylcholine esterase and alkaline phosphatase based on the generation of quantum dots by enzymatic products. Acetylcholine esterase converts acetylthiocholine into thiocholine. The latter enhances the rate of decomposition of sodium thiosulfate into H(2)S, which in the presence of cadmium sulfate yields CdS quantum dots showing a time dependent exponential growth, typical of autocatalytic processes. This assay was also applied to detect acetylcholine esterase inhibitors. Alkaline phosphatase hydrolyzes thiophosphate and yields H(2)S, which instantly reacts with Cd(2+) to give CdS quantum dots. The formation of CdS quantum dots in both reactions was followed by fluorescence spectroscopy and showed dependence on the concentration of enzyme and substrate.

  • 14.
    Shevela, Dmitriy
    et al.
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Koroidov, Sergey
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Najafpour, M Mahdi
    Messinger, Johannes
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Kurz, Philipp
    Calcium manganese oxides as oxygen evolution catalysts: o(2) formation pathways indicated by (18) o-labelling studies2011In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, no 19, p. 5415-5423Article in journal (Refereed)
    Abstract [en]

    Oxygen evolution catalysed by calcium manganese and manganese-only oxides was studied in (18) O-enriched water. Using membrane-inlet mass spectrometry, we monitored the formation of the different O(2) isotopologues (16) O(2) , (16) O(18) O and (18) O(2) in such reactions simultaneously with good time resolution. From the analysis of the data, we conclude that entirely different pathways of dioxygen formation catalysis exist for reactions involving hydrogen peroxide (H(2) O(2) ), hydrogen persulfate (HSO(5) (-) ) or single-electron oxidants such as Ce(IV) and [Ru(III) (bipy)(3) ](3+) . Like the studied oxide catalysts, the active sites of manganese catalase and the oxygen-evolving complex (OEC) of photosystem II (PSII) consist of μ-oxido manganese or μ-oxido calcium manganese sites. The studied processes show very similar (18) O-labelling behaviour to the natural enzymes and are therefore interesting model systems for in vivo oxygen formation by manganese metalloenzymes such as PSII.

  • 15. Son, Jung-Ho
    et al.
    Ohlin, C. Andre
    Johnson, Rene L.
    Yu, Ping
    Casey, William H.
    A Soluble Phosphorus-Centered Keggin Polyoxoniobate with Bicapping Vanadyl Groups2013In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 19, no 16, p. 5191-5197Article in journal (Refereed)
    Abstract [en]

    A water-soluble tetramethylammonium (TMA) salt of a novel Keggin-type polyoxoniobate has been isolated as TMA9[PV2Nb12O42]19H2O (1). This species contains a central phosphorus site and two capping vanadyl sites. Previously only a single example of a phosphorus-containing polyoxoniobate, [(PO2)3PNb9O34]15, was known, which is a lacunary Keggin ion decorated with three PO2 units. However, that cluster was isolated as an insoluble structure consisting of chains linked by sodium counterions. In contrast, the [PV2Nb12O42]9 cluster in 1 is stable over a wide pH range, as evident by 31P and 51V NMR, UV/Vis spectroscopy, and ESI-MS spectrometry. The ease of substitution of phosphate into the central tetrahedral position suggests that other oxoanions can be similarly substituted, promising a richer set of structures in this class.

  • 16.
    Thiele, Christina Marie
    et al.
    Technical University Darmstadt.
    Petzold, Katja
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Schleucher, Jürgen
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    EASY ROESY: reliable cross-peak integration in adiabatic symmetrized ROESY2009In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 15, no 3, p. 585-588Article in journal (Refereed)
    Abstract [en]

    Estimates of intramolecular distances are essential for structure determination. For medium-sized molecules, ROESY NMR is the method of choice for obtaining distances. However, the integration of ROESY cross-peaks is problematic due to the offset dependence of theintegrals and/or TOCSY artefacts. We here present EASY ROESY (rEliable Adiabatic SYmmetrized ROESY), which yields reliable intramolecular distances without sample-specific setup.

  • 17. Villa, Eric M.
    et al.
    Ohlin, C. Andre
    Casey, William H.
    Borate Accelerates Rates of Steady Oxygen-Isotope Exchange for Polyoxoniobate Ions in Water2010In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 16, no 29, p. 8631-8634Article in journal (Refereed)
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