SwePub
Sök i SwePub databas

  Extended search

Träfflista för sökning "L773:0022 3263 srt2:(2005-2009)"

Search: L773:0022 3263 > (2005-2009)

  • Result 1-50 of 93
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Angelin, Marcus, et al. (author)
  • Crystallization-induced secondary selection from a tandem driven dynamic combinatorial resolution process
  • 2008
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 73:9, s. 3593-3595
  • Journal article (peer-reviewed)abstract
    • Crystallization-induced secondary selection from a tandem driven dynamic combinatorial library is presented. In a one-pot experiment, an initial nitroaldol equilibrium was kinetically driven by a tandem reaction resulting in a subsequent dynamic library of diastereoisomers. This library was then further driven by a phase change, resulting in amplification and isolation of a highly diastereomerically enriched and synthetically interesting isoindolinone.
  •  
2.
  •  
3.
  • Arefalk, Anna, et al. (author)
  • Stereoselective Synthesis of 3-Aminoindan-1-ones and Subsequent Incorporation into HIV-1 Protease Inhibitors
  • 2006
  • In: Journal of Organic Chemistry. - 0022-3263 .- 1520-6904. ; 71:3, s. 1265-1268
  • Journal article (peer-reviewed)abstract
    • A new method for the stereoselective synthesis of 3-aminoindan-1-ones from triflates of salicylic sulfinyl imines and ethylene glycol vinyl ether has been developed. The reaction sequence starts with a regioselective Heck reaction followed by stereoselective Lewis acid mediated annulation. Acidic cleavage of the sulfinamides produced pure (R)- and (S)-3-aminoindan-1-ones, which were successfully isolated and incorporated into active HIV-1 protease inhibitors.
  •  
4.
  • Arvela, Riina K, et al. (author)
  • A reassessment of the transition-metal free suzuki-type coupling methodology.
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 70:1, s. 161-168
  • Journal article (peer-reviewed)abstract
    • We present here a reassessment of our transition-metal free Suzuki-type coupling protocol. We believe that, although the reaction can be run without the need for addition of a metal catalyst, palladium contaminants down to a level of 50 ppb found in commercially available sodium carbonate are responsible for the generation of the biaryl rather than, as previously suggested, an alternative non-palladium-mediated pathway. We present a revised methodology for Suzuki couplings using ultralow palladium concentrations for use with aryl and vinyl boronic acids and discuss the effects of the purity of the boronic acid on the reaction.
  •  
5.
  • Arvela, Riina K., et al. (author)
  • Highly regioselective internal heck arylation of hydroxyalkyl vinyl ethers by aryl halides in water
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:17, s. 6390-6396
  • Journal article (peer-reviewed)abstract
    • Highly regioselective and fast Pd(0)-catalyzed internal α-arylation of ethylene glycol vinyl ether with aryl halides was shown to be possible in water without the need for any halide scavengers or ionic liquid additives. This presents, to our knowledge, the first case of water being utilized in the selective arylation of electron-rich olefins. Resulting α-products were hydrolyzed and isolated as corresponding acetophenones in good to excellent yields when using aryl bromides and with good to moderate yields in the case of aryl iodides. Microwave irradiation was shown to be beneficial in activation of aryl chlorides toward the internal Heck arylation. The scope of the protocol was further increased to include different hydroxyalkyl vinyl ethers, these all giving selectively only branched α-products. Finally, the active role of the hydroxy group in directing the regioselectivity toward internal arylation of electron-rich olefins, even in nonpolar toluene, was revealed.
  •  
6.
  • Arvela, Riina K, et al. (author)
  • Microwave-promoted Heck coupling using ultralow metal catalyst concentrations.
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 70:5, s. 1786-1790
  • Journal article (peer-reviewed)abstract
    • We show that Heck couplings can be performed in water using microwave heating and Pd catalyst concentrations as low as 500 ppb. The methodology is simple; all that is required as the catalyst is a stock solution of palladium.
  •  
7.
  • Aydin, Juhanes, et al. (author)
  • Synthesis and catalytic application of chiral 1,1'-Bi-2-naphthol- and biphenanthrol-based pincer complexes: selective allylation of sulfonimines with allyl stannane and allyl trifluoroborate.
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:13, s. 4689-4697
  • Journal article (peer-reviewed)abstract
    • New easily accessible 1,1'-bi-2-naphthol- (BINOL-) and biphenanthrol-based chiral pincer complex catalysts were prepared for selective (up to 85% enantiomeric excess) allylation of sulfonimines. The chiral pincer complexes were prepared by a flexible modular approach allowing an efficient tuning of the selectivity of the catalysts. By employment of the different enantiomeric forms of the catalysts, both enantiomers of the homoallylic amines could be selectively obtained. Both allyl stannanes and allyl trifluoroborates can be employed as allyl sources in the reactions. The biphenanthrol-based complexes gave higher selectivity than the substituted BINOL-based analogues, probably because of the well-shaped chiral pocket generated by employment of the biphenanthrol complexes. The enantioselective allylation of sulfonimines presented in this study has important implications for the mechanism given for the pincer complex-catalyzed allylation reactions, confirming that this process takes place without involvement of palladium(0) species.
  •  
8.
  •  
9.
  • Bielawski, Marcin, et al. (author)
  • Regiospecific One-Pot Synthesis of Diaryliodonium Tetrafluoroborates from Arylboronic Acids and Aryl Iodides
  • 2008
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 73:12, s. 4602-4607
  • Journal article (peer-reviewed)abstract
    • Diaryliodonium salts have recently received considerable attention as mild arylation reagents in organic synthesis. This paper describes a regiospecific, sequential one-pot synthesis of symmetrical and unsymmetrical diaryliodonium tetrafluoroborates, which are the most popular salts in metal-catalyzed arylations. The protocol is fast and high-yielding and has a large substrate scope. Furthermore, the corresponding diaryliodonium triflates can conveniently be obtained via an in situ anion exchange.
  •  
10.
  • Billing, Johan, et al. (author)
  • C2-Symmetric Macrocyclic Carbohydrate/Amino Acid Hybrids through Copper(I)-Catalyzed Formation of 1,2,3-Triazoles
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 1520-6904 .- 0022-3263. ; 70:12, s. 4847-4850
  • Journal article (peer-reviewed)abstract
    • An efficient method was developed for the preparation of macrocyclic carbohydrate/amino acid hybrids by macrocyclization with copper(I)-catalyzed 1,2,3-triazole formation. Methyl 2-amino-6-azido-3,4-di-O-benzoyl-2,6-dideoxy--D-glucopyranoside was prepared and coupled to two different N-propiolyl dipeptides (propiolyl-Tyr-Tyr-OH and propiolyl-Arg(Mtr)-Tyr-OH) to obtain bifunctional molecules carrying one azido group and one terminal alkyne. These bifunctional molecules were cyclodimerized using Cu(I)-catalyzed 1,3-dipolar cycloaddition of azides and alkynes to form macrocycles containing two 1,2,3-triazoles. Various cyclization methods were evaluated, and the most efficient conditions were found to be CuI and N,N-diisopropylethylamine in CH3CN.
  •  
11.
  • Blid, Jan, et al. (author)
  • Lewis acid mediated asymmetric 2,3 -sigmatropic rearrangement of allylic amines. Scope and mechanistic investigation
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:4, s. 1294-1300
  • Journal article (peer-reviewed)abstract
    • [GRAPHIC] The first asymmetric [2,3]-sigmatropic rearrangement of achiral allylic amines has been realized by quaternization of the amines with an enantiomerically pure diazaborolidine and subsequent treatment with Et3N. The resultant homoallylic amines were obtained in good yields and excellent ee's. The observed diastereo- and enantioselectivities were rationalized by invoking a kinetically controlled process, and support for this model was obtained from an NMR spectroscopic investigation of the chiral Lewis acid-substrate complex. The structure of the Lewis acid-product complex was established by X-ray crystallographic analysis and supported the proposed mechanism.
  •  
12.
  • Carroll, Thomas X., et al. (author)
  • Fluorine as a π donor. Carbon 1s photoelectron spectroscopy and proton affinities of fluorobenzenes
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:5, s. 1961-1968
  • Journal article (peer-reviewed)abstract
    • The carbon 1s ionization energies for all of the carbon atoms in 10 fluorine-substituted benzene molecules have been measured by high-resolution photoelectron spectroscopy. A total of 30 ionization energies can be accurately described by an additivity model with four parameters that describe the effect of a fluorine that is ipso, ortho, meta, or para to the site of ionization. A similar additivity relationship describes the enthalpies of protonation. The additivity parameters reflect the role of fluorine as an electron-withdrawing group and as a π-electron donating group. The ionization energies and proton affinities correlate linearly, but there are four different correlations depending on whether there are 0, 1, 2, or 3 fluorines ortho or para to the site of ionization or protonation. That there are four correlation lines can be understood in terms of the ability of the hydrogens at the site of protonation to act as a π-electron acceptor. A comparison of the ionization energies and proton affinities, together with the results of electronic structure calculations, gives insight into the effects of fluorine as an electron-withdrawing group and as a π donor, both in the neutral molecule and in response to an added positive charge.
  •  
13.
  • Chorell, Erik, 1980-, et al. (author)
  • Diverse functionalization of Thiazolo ring-fused 2-Pyridones
  • 2007
  • In: Journal of Organic Chemistry. - Washington, DC 20036, USA : American Chemical Society. - 0022-3263 .- 1520-6904. ; 72:13, s. 4917-4924
  • Journal article (peer-reviewed)abstract
    • Thiazolo ring-fused 2-pyridones have proven to be highly interesting scaffolds for the development of biologically active compounds. Many methods are today available to introduce a variety of substituents in the 2-pyridone part of the heterocycle. Herein we disclose how a diverse set of substituents can be introduced in the thiazolo ring, with possibilities to vary also the spatial arrangement of the substituents. A key intermediate is the oxidized framework 9 for which an effective synthesis is described. The thiazolo part of this system can be substituted either via conjugate additions, resulting in trans selectivity, or via microwave-assisted Heck couplings that result in unsaturated aryl-substituted analogues. The scaffold can also be lithiated followed by the addition of various electrophiles, which increases the diversification potential substantially, as exemplified with the introduction of halogens, alkyl, acyl, and amide substituents.
  •  
14.
  •  
15.
  • Dahlén, Anders, 1977, et al. (author)
  • Estimating the limiting reducing power of SmI2/H2O/amine and YbI2/H2O/amine by efficient reduction of unsaturated hydrocarbons.
  • 2006
  • In: The Journal of organic chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:4, s. 1576-80
  • Journal article (peer-reviewed)abstract
    • The mixture of samarium diiodide, amine, and water (SmI2/H2O/Et3N) is known to be a particularly powerful reductant, but until now the limiting reducing power has not been determined. A series of unsaturated hydrocarbons with varying half-wave reduction potentials (E(1/2) = -1.6 to -3.4 V, vs SCE) have been treated with SmI2/H2O/Et3N and YbI2/H2O/Et3N, respectively. All hydrocarbons with potentials of -2.8 V or more positive were readily reduced with SmI2/H2O/Et3N, whereas all hydrocarbons with potentials of -2.3 V or more positive were readily reduced using YbI2/H2O/Et3N. This defines limiting values of the chemical reducing power of SmI2/H2O/Et3N to -2.8 V and of YbI2/H2O/Et3N to -2.3 V vs SCE.
  •  
16.
  • Dahlén, Kristian, 1973, et al. (author)
  • Synthesis of 2,3,6,8-tetrasubstituted chromone scaffolds.
  • 2006
  • In: The Journal of organic chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:18, s. 6863-6871
  • Journal article (peer-reviewed)abstract
    • A useful and efficient synthetic strategy to 2,3,6,8-tetrasubstituted chromone derivatives has been developed. 2-Aryl/styryl-8-bromo-6-chloro-3-hydroxychromone derivatives were synthesized and used as scaffolds by introducing a variety of substituents in the 3-, 6-, and 8-positions using palladium-mediated reactions. Excellent regioselectivity in all positions could be obtained by performing reactions in the 8-position first, in which Stille, Heck, Suzuki, and Sonogashira reactions gave good to excellent yields of product (63-98%). Stille and Heck reactions in the 6-position also gave the desired products in good yields (64-86%). The hydroxy group in the 3-position was activated as a triflate and used in productive Stille reactions (63-94%). This hydroxyl group was also used in O-alkylation reactions with different functionalized alkyl bromides (57-88%). The flavonoids, which are based on the chromone structure, and other related ring systems, have several interesting biological activities. The chromones are also interesting structural scaffolds, and they have for example been designed to be used as mimetics of short peptides. The versatile applicability of chromone derivatives and especially their potential use in drug discovery implicates the importance of access to efficient synthetic routes to such compounds.
  •  
17.
  •  
18.
  •  
19.
  • Dong, Hai, et al. (author)
  • Efficient Synthesis of β-D-Mannosides and β-D-Talosides by Double Parallel or Double Serial Inversion
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:10, s. 3694-3701
  • Journal article (peer-reviewed)abstract
    • A neighboring equatorial ester group plays a highly important role in the Lattrell-Dax (nitrite-mediated) carbohydrate epimerization reaction, inducing the formation of inversion compounds in good yields. On the basis of this effect, efficient synthetic routes to beta-D-mannosides and beta-D-talosides, from the corresponding beta-D-galactosides and beta-D-glucosides, have been designed. The present routes are based on multiple regioselective acylation via the respective stannylene intermediates, followed by inversions to the corresponding manno- and talopyranoside structures by nitrite or acetate substitution. It was found that the ester group was able to induce the inversion of its two neighboring groups in high yields following either a double parallel or a double serial inversion process. By combination of direct inversion, and neighboring- as well as remote-group participation, several beta-D-mannoside and beta-D-taloside derivatives were very conveniently obtained in good yields.
  •  
20.
  • Dong, Hai, et al. (author)
  • Reagent-dependent regioselective control in multiple carbohydrate esterifications
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:4, s. 1499-1502
  • Journal article (peer-reviewed)abstract
    • Regioselective control in organotin-mediated multiple acylation of carbohydrates is presented. The acylation reagent could be efficiently used to direct the product formation. Reagent-dependent thermodynamic and kinetic control and dynamic assistance mechanisms are suggested, resulting in the efficient preparation of building blocks that normally require many steps with traditional synthesis.
  •  
21.
  • Dong, Hai, et al. (author)
  • Stereospecific Ester Activation in Nitrite-Mediated Carbohydrate Epimerization
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:8, s. 3306-3309
  • Journal article (peer-reviewed)abstract
    • The Lattrell-Dax method of nitrite-mediated substitution of carbohydrate triflates is an efficient method to generate structures of inverse configuration. In the present study, epimerization of gluco- and galactopyranoside derivatives to the corresponding allo- and gulopyranoside structures by triflation/nitrite treatment has been investigated. It was found that a neighboring ester group was essential for the reactivity of the nitrite-mediated triflate, inversion. Furthermore, a good inversion yield also depended on the relative configuration of the neighboring ester group to the triflate. Only with the ester group in the equatorial position, whatever the configuration of the triflate, did the reaction proceed smoothly, whereas a neighboring axial ester group proved largely inefficient. The results were subsequently used to predict the inversion of glucopyranoside derivatives to the mannopyranoside epimers.
  •  
22.
  • Enquist, Per-Anders, et al. (author)
  • ESI-MS Detection of Proposed Reaction Intermediates in the Air-Promoted and Ligand-Modulated Oxidative Heck Reaction
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:23, s. 8779-8786
  • Journal article (peer-reviewed)abstract
    • Electrospray ionization mass spectrometry (ESI-MS) and subsequent MS/MS analyses were used to directly detect palladium-containing cationic reaction intermediates in a ligand controlled palladium(II)-catalyzed oxidative Heck arylation. All potential intermediates were observed as dmphen-ligated palladium(II) species, suggesting that the dmphen bidentate ligand is attached to the metal center during the entire catalytic cycle. The study supports previous mechanistic propositions and provides new information regarding the composition of aryl-containing Pd(II) complexes in an ongoing oxidative Heck reaction. In addition, sodium acetate was found to be a useful base alternative to previously used tertiary amines.
  •  
23.
  •  
24.
  • Fang, Yao-ren, et al. (author)
  • The Effect of Solvent on the Structure of the Transition State for the SN2 Reaction between Cyanide Ion and Ethyl Chloride in DMSO and THF Probed with Six Different Kinetic Isotope Effects
  • 2006
  • In: J. Org. Chem. - : American Chemical Society (ACS). ; :71, s. 4742-4747
  • Journal article (peer-reviewed)abstract
    • The secondary a- and B-deuterium, the a-carbon, the nucleophile carbon, the nucleophile nitrogen, and the chlorine leaving group kinetic isotope effects forthe SN2 reaction between cyanide ion an dethyl chloride were determined in the very slightly polar solvent THF at 30 C. A comparison of these KIEs with those reported earlier for the same reaction in the polar solvent DMSO shows that the transition state in THF is only sligthly tighter with very slightly shorter NC-Ca-CI bonds. This minor change in transition state structure does not account for the different transition structures that were earlier suggested by interpreting the experimental KIEs and the gas-phase calculations, respectively. It therefore seems unlikely that the different transition states suggested by the two methods are due to the lack of appropriate solvent modeling in the theoretical calculations. Previously it was predicted that the transition state of SN2 reactions where the nucleophile and the leaving group have the same charge would be unaffected by a charge in solvent. The experimental KIEs support this view.
  •  
25.
  • Faure, Regis, et al. (author)
  • Synthesis of a library of xylogluco-oligosaccharides for active-site mapping of xyloglucan endo-transglycosylase
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:14, s. 5151-5161
  • Journal article (peer-reviewed)abstract
    • [GRAPHICS] Complex oligosaccharides containing R-D-xylosyl-(1 -> 6)-beta-D-glucosyl residues and unsubstituted beta-(1 -> 4)-linked D-glucosyl units were readily synthesized using enzymatic coupling catalyzed by the Cel7B E197A glycosynthase from Humicola insolens. Constituting this library required four key steps: ( 1) preparing unprotected building blocks by chemical synthesis or enzymatic degradation of xyloglucan polymers; (2) generating the donor synthon in the enzymatic coupling by temporarily introducing a lactosyl motif on the 4-OH of the terminal glucosyl units of the xylogluco-oligosaccharides; ( 3) synthesizing the corresponding R-fluorides, followed by their de-O-acetylation and the glycosynthase-catalyzed condensation of these donors onto various acceptors; and (4) enzymatically releasing lactose or galactose from the reaction product, affording the target molecules in good overall yields. These complex oligosaccharides proved useful for mapping the active site of a key enzyme in plant cell wall biosynthesis and modification: the xyloglucan endo-transglycosylase (XET). We also report some preliminary enzymatic results regarding the efficiency of these compounds.
  •  
26.
  • Fjellander, Ester, 1982-, et al. (author)
  • Atropoisomerism in Phosphepines and Azepines
  • 2009
  • In: Journal of Organic Chemistry. - Washington DC : American Chemical Society. - 0022-3263 .- 1520-6904. ; 74:23, s. 9120-9125
  • Journal article (peer-reviewed)abstract
    • Free energy barriers to biaryl tropoinversion in metal complexes with tropos phosphepine and azepine ligands were determined by temperature-dependent P-31 NMR inversion-transfer experiments and line shape analysis of the temperature-dependent H-1 NMR spectra, respectively. The barrier in the PdCl2 complex of the azepine ligand was found to be slightly higher than that of the corresponding free ligand. Studies of a tridentate azepine ligand Suggested that Configurational change takes place without prior decoordination from the metal.
  •  
27.
  •  
28.
  • Fransson, Ann-Britt L., et al. (author)
  • Enzymatic Resolution, Desymmetrization and Dynamic Kinetic Asym-metric Transformation of 1,3-Cycloalkanediols
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society. - 0022-3263 .- 1520-6904. ; 71:17, s. 6309-6316
  • Journal article (peer-reviewed)abstract
    • An efficient desymmetrization of cis-1,3-cyclohexanediol to (1S,3R)-3-(acetoxy)-1-cyclohexanol ((R,S)-2a) was performed via Candida antarctica lipase B (CALB)-catalyzed transesterification, in high yield (up to 93%) and excellent enantioselectivity (ee's up to >99.5%). (R,R)-Diacetate ((R,R)-3a) was obtained in a DYKAT process at room temperature from (1S,3R)-3-acetoxy-1-cyclohexanol ((R,S)-2a), in a high trans/cis ratio (91:9) and in excellent enantioselectivity of >99%. Metal- and enzyme-catalyzed dynamic transformation of cis/trans-1,3-cyclohexanediol using PS-C gave a high diastereoselectivity for cis-diacetate (cis/trans = 97:3). The (1R,3S)-3-acetoxy-1-cyclohexanol (ent-(R,S)-2a) was obtained from cis-diacetate by CALB-catalyzed hydrolysis in an excellent yield (97%) and selectivity (>99% ee). By deuterium labeling it was shown that intramolecular acyl migration does not occur in the transformation of cis-monoacetate to the cis-diacetate.
  •  
29.
  • Fransson, Ann-Britt L., et al. (author)
  • Kinetic Resolution and Chemoenzymatic Dynamic Kinetic Resolution of Functionalized γ-Hydroxy Amides
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 70:7, s. 2582-2587
  • Journal article (peer-reviewed)abstract
    • An efficient kinetic resolution of racemic gamma-hydroxy amides 1 was performed via Pseudomas cepacia lipase (PS-C)-catalyzed transesterification. The enzyme PS-C tolerates both variation in the chain length and different functionalities giving good to high enantioselectivity (E values of up to > 250). The combination of enzymatic kinetic resolution with a ruthenium-catalyzed racemization led to a dynamic kinetic resolution. The use of 2,4-dimethyl-3-pentanol as a hydrogen source to suppress ketone formation in the dynamic kinetic resolution yields the corresponding acetates in good yield and good to high enantioselectivity (ee's up to 98%). The synthetic utility of this procedure was illustrated by the practical synthesis of the versatile intermediate gamma-lactone (R)-5-methyltetrahydrofuran-2-one.
  •  
30.
  • Fridén-Saxin, Maria, 1979, et al. (author)
  • Synthesis of 2-alkyl-substituted chromone derivatives using microwave irradiation.
  • 2009
  • In: The Journal of organic chemistry. - : American Chemical Society (ACS). - 1520-6904 .- 0022-3263. ; 74:7, s. 2755-9
  • Journal article (peer-reviewed)abstract
    • A base-promoted condensation between 2-hydroxyacetophenones and aliphatic aldehydes has been studied. The reaction has been optimized to afford 2-alkyl-substituted 4-chromanones in an efficient manner using microwave heating. Performing the reaction using diisopropylamine in EtOH at 170 degrees C for 1 h gave moderate to high yields (43-88%). The 4-chromanones could be further converted into highly functionalized 2,3,6,8-tetrasubstituted chromones in which a 3-substituent (acetate, amine, or bromine) was introduced via straightforward chemical transformations.
  •  
31.
  • Frölander, Anders, et al. (author)
  • Conformational preferences and enantiodiscrimination of phosphino-4-(1-hydroxyalkyl)oxazoline-metal-olefin complexes resulting from an OH-metal hydrogen bond
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 70:24, s. 9882-9891
  • Journal article (peer-reviewed)abstract
    • Phosphinooxazolines carrying (1-hydroxy-1-phenyl)methyl and (1-methoxy-1-phenyl)methyl substituents in the 4 position of the oxazoline ring exhibit contrasting behavior in Pd-and Ir-catalyzed allylic alkylations. Whereas catalysts with the methoxy-containing ligand generally provide products with high ee's, use of catalysts prepared from the hydroxy-containing ligand results in products with low ee's or even racemates. DFT calculations suggest the presence of a hydrogen bond with Pd(0) as the proton acceptor in the hydroxy-containing olefin-Pd(0) complexes, which induces a conformational change in the ligand, leading to different stereoselectivity.
  •  
32.
  • Grundberg, Hans, et al. (author)
  • Absence of reverse anomeric effect in furanosides
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 1520-6904 .- 0022-3263. ; 71:16, s. 5892-5896
  • Journal article (peer-reviewed)abstract
    • A series of conformationally restricted N-"furanosides" has been synthesized, where the carbons of the tetrahydrofuran ring are kept in one plane by a rigid norbornane skeleton, permitting only the ring oxygen to move above or below the tetrahydrofuran ring plane. This causes the substituents of the anomeric carbon to occupy a pseudoaxial or a pseudoequatorial position. On protonation of these "norbornane-furanosides" with trifluoromethanesulfonic acid, all three compounds exhibited decreasing coupling constants for the anomeric proton, indicating a shift toward the pseudoaxial conformation. The coupling constant measurements were supported by volume integration of NOESY cross-peaks, which also showed a change toward the pseudoaxial conformation upon protonation of the nitrogen. These results provide no evidence for the so-called reverse anomeric effect; on the contrary they are in full agreement with a small normal anomeric effect.
  •  
33.
  • Gustafsson, Tomas, et al. (author)
  • Synthesis of a C-Glycoside Analogue of -D-Galactosyl Hydroxylysine and Incorporation in a Glycopeptide from Type II Collagen
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 71:5, s. 1911-9
  • Journal article (peer-reviewed)abstract
    • A stereoselective synthesis of the C-glycoside analogue of -D-galactosyl-(5R,2S)-hydroxylysine (1) has been achieved starting from tetra-O-benzyl-D-galactopyranosyl lactone. The synthesis involved establishment of three stereogenic centers in an unambiguous manner. A facially selective Grignard reaction followed by a silane reduction was used for the anomeric position of the C-galactose residue. An Evans allylation established the configuration of the -aminomethylene group of the hydroxylysine moiety, whereas an asymmetric hydrogenation utilizing Burk's catalyst was used for the -amino acid moiety itself. The synthesis was completed in 17 steps with an overall yield of 18%, resulting in the most complex and functionalized C-glycoside analogue of a naturally occurring glycosylated amino acid prepared to date. In addition, amino acid 1 was incorporated in a glycopeptide from type II collagen known to be crucial for the response of autoimmune T cells obtained in models of rheumatoid arthritis. A preliminary immunological study revealed that four out of five members in a panel of T cell hybridomas were able to recognize this C-linked glycopeptide when presented by Aq class II MHC molecules.
  •  
34.
  • Hagberg, Daniel P., et al. (author)
  • Tuning the HOMO and LUMO Energy Levels of Organic Chromophores For Dye Sensitized Solar Cells
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; :72, s. 9550-9556
  • Journal article (peer-reviewed)abstract
    • A series of organic chromophores have been synthesized in order to approach optimal energy level composition in the TiO2-dye-iodide/triiodide system in the dye-sensitized solar cells. HOMO and LUMO energy level tuning is achieved by varying the conjugation between the triphenylamine donor and the cyanoacetic acid acceptor. This is supported by spectral and electrochemical experiments and TDDFT calculations. These results show that energetic tuning of the chromophores was successful and fulfilled the thermodynamic criteria for dye-sensitized solar cells, electrical losses depending on the size and orientation of the chromophores were observed.
  •  
35.
  • Hartikka, Antti, et al. (author)
  • Tetrazolic Acid Functionalized Dihydroindol : Rational Design of a Highly Selective Cyclopropanation Organocatalyst
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:15, s. 5874-5877
  • Journal article (peer-reviewed)abstract
    • Herein we wish to report our development of an improved catalyst (S)-(-)-indoline-2-yl-1H-tetrazole (1) for the enantioselective organocatalyzed cyclopropanation of α,β-unsaturated aldehydes with sulfur ylides. The new organocatalyst readily facilitates the enantioselective organocatalytic cyclopropanation, providing cyclized product in excellent diastereoselectivities ranging from 96% to 98% along with enantioselectivities exceeding 99% enantiomeric excess for all reacted α,β-unsaturated aldehydes. The new catalyst provides the best results so far reported for intermolecular enantioselective organocatalyzed cyclopropanation.
  •  
36.
  • Hederos, Markus, et al. (author)
  • Synthesis of the core tetrasaccharide of Trypanosoma cruzi glycoinositolphospholipids : manp(α1→6)-Manp(α1→4)-6-(2-aminoethylphosphonic acid)-GlcNp(α1→6)-myo-Ins-1-PO4
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 70:18, s. 7196-7207
  • Journal article (peer-reviewed)abstract
    • Synthesis of the core tetrasaccharide Manp(α1→6)-Manp(α1→4)-6-(2-aminoethylphosphonic acid)-GlcNp(α1→6)-myo-Ins-1-PO4, found in glycoinositolphospholipids of Trypanosoma cruzi parasites, is described. The key building block, 6-O-(2-azido-3-O-benzyl-6-O-((2-benzyloxycarbonylaminoethyl)phosphonic acid benzyl ester)-2-deoxy-α-d-glucopyranosyl)-1-di-O-benzylphosphoryl-4,5-O-isopropylidene-2,3-O-(d-1,7,7-trimethyl[2,2,1]bicyclohept-6-ylidene)-d-myo-inositol, was synthesized using a partially protected glucosyl d-camphorinositolphosphate and a (2-benzyloxycarbonylaminoethyl)phosphonic acid derivative in a regioselective phosphonate esterfication. Elongation with ethyl 2-O-benzoyl-3,4,6-tri-O-benzyl-α-d-mannopyranosyl-(1→6)-2,3,4-tri-O-benzyl-1-α-d-thiomannopyranoside using dimethyl(methylthio)sulfonium trifluoromethanesulfonate gave a fully protected tetrasaccharide which was successfully deprotected subsequently with sodium methoxide, sodium in liquid ammonia, and aq hydrochloric acid to give title compound.
  •  
37.
  • Hirner, Sebastian, et al. (author)
  • Synthesis of alpha-Amino Amides via N,O-Acetals Derived from Weinreb Amides
  • 2009
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 74:20, s. 7798-7803
  • Journal article (peer-reviewed)abstract
    • An easy and straightforward synthesis of alpha-amino amides via a base-mediated rearrangement of modified Weinreb amides into N,O-acetals is presented. Subsequent arylation, alkylation, alkenylation, or alkynylation of this intermediate affords the corresponding alpha-amino amides in excellent yields. Furthermore, a more generalized protocol for the alpha-arylation of Weinreb amides lacking an alpha-amino moiety is also discussed.
  •  
38.
  • Honcharenko, Dmytro, et al. (author)
  • Modulation of Pyrene Fluorescence in DNA Probes Depends upon the Nature of the Conformationally Restricted Nucleotide
  • 2008
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 73:7, s. 2829-2842
  • Journal article (peer-reviewed)abstract
    • The DNA probes (ODNs) containing a 2'-N-(pyren-1-yl)-group on the conformationally locked nucleosides [2'-N-(pyren-1-yl)carbonyl-azetidine thymidine, Aze-pyr (X), and 2'-N-(pyren-1-yl)carbonyl-aza-ENA thymidine, Aza-ENA-pyr (Y)], show that they can bind to complementary RNA more strongly than to the DNA. The Aze-pyr (X) containing ODNs with the complementary DNA and RNA duplexes showed an increase in the fluorescence intensity (measured at lambda em approximately 376 nm) depending upon the nearest neighbor at the 3'-end to X [dA ( approximately 12-20-fold) > dG ( approximately 9-20-fold) > dT ( approximately 2.5-20-fold) > dC ( approximately 6-13-fold)]. They give high fluorescence quantum yields (Phi F = 0.13-0.89) as compared to those of the single-stranded ODNs. The Aza-ENA-pyr (Y)-modified ODNs, on the other hand, showed an enhancement of the fluorescence intensity only with the complementary DNA (1.4-3.9-fold, Phi F = 0.16-0.47); a very small increase in fluorescence is also observed with the complementary RNA (1.1-1.7-fold, Phi F = 0.17-0.22), depending both upon the site of the Y modification introduced as well as on the chemical nature of the nucleobase adjacent to the modification site into the ODN. The fluorescence properties, thermal denaturation experiments, absorption, and circular dichroism (CD) studies with the X- and Y-modified ODNs in the form of matched homo- and heteroduplexes consistently suggested (i) that the orientation of the pyrene moiety is outside the helix of the nucleic acid duplexes containing a dT-d/rA base pair at the 3'-end of the modification site for both X and Y types of modifications, and (ii) that the microenvironment around the pyrene moiety in the ODN/DNA and ODN/RNA duplexes is dictated by the chemical nature of the conformational constraint in the sugar moiety, as well as by the nature of neighboring nucleobases. The pyrene fluorescence emission in both X and Y types of the conformationally restricted nucleotides is found to be sensitive to a mismatched base present in the target RNA: (i) The X-modified ODN showed a decrease ( approximately 37-fold) in the fluorescence intensity (measured at lambda em approximately 376 nm) upon duplex formation with RNA containing a G nucleobase mismatch (dT-rG pair instead of dT-rA) opposite to the modification site. (ii) In contrast, the Y-modified ODN in the heteroduplex resulted in a approximately 3-fold increase in the fluorescence intensity upon dT-rG mismatch, instead of matched dT-rA pair, in the RNA strand. Our data corroborate that the pyrene moiety is intercalated in the X-modified mismatched ODN/RNA (G mismatch) heteroduplex as compared to that of the Y-modified ODN/RNA (G mismatch) heteroduplex, in which it is located outside the helix.
  •  
39.
  •  
40.
  •  
41.
  • Johansson, M. J., et al. (author)
  • Modular asymmetric synthesis of P-chirogenic beta-amino phosphine boranes
  • 2008
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 73:12, s. 4458-4463
  • Journal article (peer-reviewed)abstract
    • (Chemical Equation Presented) A short concise route to β- aminophosphine boranes is presented via the desymmetrization of prochiral phosphine boranes, forming P-chirogenic aldehydes that are rapidly transformed to the target compounds employing reductive amination under microwave irradiation. This sequence provides a modular route to P-chirogenic P,N ligands, and in addition, the intermediate aldehydes are versatile P-chiral building blocks for ligand design in general. An alternative pathway via the corresponding α-carboxyphosphines is also described. The ligands were subsequently evalutated in the asymmetric conjugate addition of diethylzinc to trans-β-nitrostyrene. © 2008 American Chemical Society.
  •  
42.
  • Johnsson, Richard, et al. (author)
  • Reductive openings of acetals: Explanation of regioselectivity in borane reductions by mechanistic studies
  • 2008
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 1520-6904 .- 0022-3263. ; 73:14, s. 5226-5232
  • Journal article (peer-reviewed)abstract
    • The mechanisms of regioselective reductive openings of acetals were investigated in several model systems by a combination of Hammett plots, kinetic experiments, density functional calculations, and B-11 NMR. The regioselectivity of borane reductions of cyclic acetals can be controlled by the choice of borane. Lewis acid activation of BH3 center dot NMe3 increases the reaction rate and renders the borane the most electrophilic species, which associates to the more electron-rich oxygen of the acetal. In contrary, without activation, the regioselectivity is instead directed by the Lewis acid, as exemplified by the reaction with BH3 center dot THF.
  •  
43.
  • Johnsson, Richard, et al. (author)
  • Regioselective reductive openings of acetals; Mechanistic details and synthesis of fluorescently labeled compounds
  • 2006
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 1520-6904 .- 0022-3263. ; 71:9, s. 3444-3451
  • Journal article (peer-reviewed)abstract
    • Regioselective reductive openings of mixed phenolic-benzylic acetals, using BH3 center dot NMe3 center dot AlCl3, was investigated, and a mechanism where the outcome is directed by the electrostatic potential of the two oxygen atoms is presented. The regioselective acetal opening was used in the synthesis of a fluorescently labeled analogue to antiproliferative xylosides. The fluorescently labeled xyloside was tested for uptake, anti proliferative activity, and glycosaminoglycan priming in different cell lines. The xyloside was taken up by all cell lines but did not initiate glycosaminoglycan biosynthesis.
  •  
44.
  • Jäger, Michael, et al. (author)
  • Synthesis and Characterization of 2,6-Di(quinolin-8-yl)pyridines : New Ligands for Bistridentate RuII Complexes with Microsecond Luminescent Lifetimes
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:26, s. 10227-10230
  • Journal article (peer-reviewed)abstract
    • The synthesis of 4-substituted and 4-aryl-substituted 2,6-di(quinolin-8-yl)pyridines is described. The tridentate ligands were prepared via a palladium-catalyzed Suzuki−Miyaura cross-coupling reaction or via a one-step ring-forming reaction generating the central pyridine ring. X-ray crystal structures and 1H NMR shifts are discussed and compared to the corresponding data for a RuII bistridentate complex. Intramolecular stacking of two quinoline units in the RuII complex is suggested by 1H NMR data and also observed in the X-ray structure.
  •  
45.
  • Kato, Haruhisa, et al. (author)
  • J. Org. Chem.
  • 2005
  • In: J. Org. Chem.. - : American Chemical Society (ACS). ; :70, s. 9495-9504
  • Journal article (peer-reviewed)
  •  
46.
  • Kato, H., et al. (author)
  • Z/E-photoisomerizations of olefins with 4nπ- or (4n + 2)π-electron substituents: Zigzag variations in olefin properties along the T1 state energy surfaces
  • 2005
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 70:23, s. 9495-9504
  • Journal article (peer-reviewed)abstract
    • A quantum chemical study has been performed to assess changes in aromaticity along the T1 state Z/E-isomerization pathways of annulenyl-substituted olefins. It is argued that the point on the T1 energy surface with highest substituent aromaticity corresponds to the minimum. According to Baird (J. Am. Chem. Soc. 1972, 94, 4941), aromaticity and antiaromaticity are interchanged when going from S0 to T1. Thus, olefins with S0 aromatic substituents (set A olefins) will be partially antiaromatic in T1 and vice versa for olefins with S 0 antiaromatic substituents (set B olefins). Twist of the C=C bond to a structure with a perpendicular orientation of the 2p(C) Orbitals ( 3p*) in T1 should lead to regaining substituent aromaticity in set A and loss of aromaticity in set B olefins. This hypothesis is verified through quantum chemical calculations of T1 energies, geometries (bond lengths and harmonic oscillator measure of aromaticity), spin densities, and nucleus independent chemical shifts whose differences along the T1 PES display zigzag dependencies on the number of π-electrons in the annulenyl substituent of the olefin. Aromaticity changes are reflected in the profiles of the T1 potential energy surfaces (T1 PESs) for Z/E-isomerizations because olefins in set A have minima at 3p* whereas those in set B have maxima at such structures. The proper combination (fusion) of the substituents of set A and B olefins could allow for design of novel optical switch compounds that isomerize adiabatically with high isomerization quantum yields.
  •  
47.
  •  
48.
  • Kumar, Sangit, et al. (author)
  • Antioxidant Profile of Ethoxyquin and Some of Its S, Se, and Te Analogues
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:16, s. 6046-6055
  • Journal article (peer-reviewed)abstract
    • (Chemical Equation Presented) 6-(Ethylthio)-, 6-(ethylseleno)-, and 6-(ethyltelluro)-2,2,4-trimethyl-1,2-dihydroquinoline-three heavier chalcogen analogues of ethoxyquin-were prepared by dilithiation of the corresponding 6-bromodihydroquinoline followed either by treatment with the corresponding diethyl dichalcogenide (sulfur derivative) or by insertion of selenium/tellurium into the carbon-lithium bond, oxidation to a diaryl dichalcogenide, borohydride reduction, and finally alkylation of the resulting areneselenolate/ arenetellurolate. Ethoxyquin, its heavier chalcogen analogues, and the corresponding 6-PhS, 6-PhSe, and 6-PhTe derivatives were assayed for both their chain-breaking antioxidant capacity and their ability to catalyze reduction of hydrogen peroxide in the presence of a stoichiometric amount of a thiol reducing agent (thiol peroxidase activity). Ethoxyquin itself turned out to be the best inhibitor of azo-initiated peroxidation of linoleic acid in a water/chlorobenzene two-phase system. In the absence of N-acetylcysteine as a coantioxidant in the aqueous phase, it inhibited peroxidation as efficiently as α-tocopherol but with a more than 2-fold longer inhibition time. In the presence of 0.25 mM coantioxidant in the aqueous phase, the inhibition time was further increased by almost a factor of 2. This is probably due to thiol-mediated regeneration of the active antioxidant across the lipid-aqueous interphase. The ethyltelluro analogue 1d of ethoxyquin was a similarly efficient quencher of peroxyl radicals compared to the parent in the two-phase system, but less regenerable. Ethoxyquin was found to inhibit azo-initiated oxidation of styrene in the homogenous phase (chlorobenzene) almost as efficiently (k inh = (2.0 ± 0.2) × 106 M-1 s -1) as α-tocopherol with a stoichiometric factor n = 2.2 ± 0.1. At the end of the inhibition period, autoxidation was additionally retarded, probably by ethoxyquin nitroxide formed during the course of peroxidation. The N-H bond dissociation enthalpy of ethoxyquin (81.3 ± 0.3 kcal/mol) was determined by a radical equilibration method using 2,6-dimethoxyphenol and 2,6-di-tert-butyl-4-methylphenol as equilibration partners. Among the investigated compounds, only the tellurium analogues 1d and, less efficiently, 1g had a capacity to catalyze reduction of hydrogen peroxide in the presence of thiophenol. Therefore, analogue 1d is the only antioxidant which is multifunctional (chain-breaking and preventive) in character and which can act in a truly catalytic fashion to decompose both peroxyl radicals and organic hydroperoxides in the presence of suitable thiol reducing agents.
  •  
49.
  •  
50.
  • Kumar, Sangit, et al. (author)
  • Regenerable Chain-Breaking 2,3-Dihydrobenzo[b]selenophene-5-ol Antioxidants
  • 2007
  • In: Journal of Organic Chemistry. - : American Chemical Society (ACS). - 0022-3263 .- 1520-6904. ; 72:7, s. 2583-2595
  • Journal article (peer-reviewed)abstract
    • A series of 2,3-dihydrobenzo[b]selenophene-5-ol antioxidants was prepared by subjecting suitably substituted allyl 4-methoxyphenyl selenides to microwave-induced seleno-Claisen rearrangement/intramolecular Markovnikov hydroselenation followed by boron tribromide-induced O-demethylation. The novel antioxidants were assayed for their capacity to inhibit azo-initiated peroxidation of linoleic acid in a water/chlorobenzene two-phase system containing N-acetylcysteine as a thiol reducing agent in the aqueous phase. Antioxidant efficiency as determined by the inhibited rate of peroxidation, Rinh, increased with increasing methyl substitution (Rinh = 46−26 μM/h), but none of the compounds could match α-tocopherol (Rinh = 22 μM/h). Regenerability as determined by the inhibition time, Tinh, in the presence of the thiol regenerating agent decreased with increasing methyl substitution. Thus, under conditions where the unsubstituted compound 5a inhibited peroxidation for more than 320 min, α-tocopherol worked for 90 min and the trimethylated antioxidant 5g for 60 min only. Sampling of the aqueous phase at intervals during peroxidation using antioxidant 5a showed that N-acetylcysteine was continuously oxidized with time to the corresponding disulfide. In the absence of the regenerating agent, compounds 5 inhibited peroxidation for 50−60 min only. A (RO)B3LYP/LANL2DZdp//B3LYP/LANL2DZ model was used for the calculation of homolytic O−H bond dissociation enthalpies (BDE) and adiabatic ionization potentials (IP) of phenolic antioxidants 5. Both BDE (80.6−76.3 kcal/mol) and IP (163.2−156.0 kcal/mol) decrease with increasing methyl substitution. The phenoxyl radical corresponding to phenol 5g gave an intense ESR signal centered at g = 2.0099. The H−O bond dissociation enthalpy of the phenol was determined by a radical equilibration method using BHA as an equilibration partner. The observed BDE (77.6 ± 0.5 kcal/mol) is in reasonable agreement with calculations (76.3 kcal/mol). As judged by calculated log P values, the lipophilicity of compounds 5 increased slightly when methyl groups were introduced into the phenolic moiety (2.9 > C log P < 4.2). The capacity of compounds 5a (kinh = 3.8 × 105 M-1 s-1) and 5g (kinh = 1.5 × 106 M-1 s-1) to inhibit azo-initiated autoxidation of styrene in the homogeneous phase (chlorobenzene) was also studied. More efficient regeneration at the lipid−aqueous interphase is the most likely explanation why the intrinsically poorest antioxidant 5a can outperform its analogues as well as α-TOC in the two-phase system. Possible mechanisms of regeneration are discussed and evaluated.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-50 of 93
Type of publication
journal article (93)
Type of content
peer-reviewed (91)
other academic/artistic (2)
Author/Editor
Larhed, Mats (13)
Bäckvall, Jan-Erling (7)
Nilsson, Peter (6)
Chattopadhyaya, Jyot ... (6)
Ramström, Olof (5)
Hallberg, Anders (5)
show more...
Engman, Lars (4)
Wu, Xiongyu (4)
Pei, Zhichao (4)
Dong, Hai (4)
Somfai, Peter (4)
Leijondahl, Karin (4)
Arvidsson, Per I. (3)
Ellervik, Ulf (3)
Luthman, Kristina, 1 ... (3)
Grøtli, Morten, 1966 (3)
Bäckvall, Jan-E. (3)
Honcharenko, Dmytro (3)
Valgimigli, Luca (3)
Arvela, Riina K (3)
Matsson, Olle (3)
Zhou, Chuanzheng (3)
Bogár, Krisztián (3)
Fransson, Ann-Britt ... (3)
Eriksson, Lars (2)
Szabó, Kálmán J. (2)
Ladenstein, R (2)
Olofsson, Berit (2)
Johnsson, Richard (2)
Fischer, M. (2)
Garg, Neeraj (2)
Ottosson, Henrik (2)
Sun, Licheng (2)
Amorati, Riccardo (2)
Pedulli, Gian Franco (2)
Enquist, Per-Anders (2)
Moberg, Christina (2)
Angelin, Marcus (2)
Arefalk, Anna (2)
Bergquist, Karl-Erik (2)
Leadbeater, Nicholas ... (2)
Szabó, Kálmán (2)
Bacher, A (2)
Cushman, M (2)
Eriksson, Jonas (2)
Liu, Yi (2)
Rönn, Robert (2)
Borén, Linnéa (2)
Xu, Yongmei (2)
Norgren, Anna S. (2)
show less...
University
Uppsala University (38)
Royal Institute of Technology (20)
Stockholm University (20)
Lund University (6)
Karolinska Institutet (5)
University of Gothenburg (4)
show more...
Chalmers University of Technology (3)
Umeå University (2)
Linköping University (2)
show less...
Language
English (87)
Undefined language (6)
Research subject (UKÄ/SCB)
Natural sciences (55)
Medical and Health Sciences (9)
Engineering and Technology (1)

Year

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view