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  • 1.
    Ahlford, Katrin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zaitsev, Alexey B.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ekström, Jesper
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Adolfsson, Hans
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    A Simple and Efficient Catalyst System for the Asymmetric Transfer Hydrogenation of Ketones2007Inngår i: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, nr 16, s. 2541-2544Artikkel i tidsskrift (Fagfellevurdert)
  • 2.
    Akhtar, Tashfeen
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Cumpstey, Ian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Investigations into the synthesis of amine-linked neodisaccharides2007Inngår i: Tetrahedron Letters, ISSN 0040-4039, Vol. 48, s. 8673-8677Artikkel i tidsskrift (Fagfellevurdert)
  • 3.
    Ali, Tara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Structural Studies of O-Polysaccharides from Diarrhoeal Escherichia coli2007Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This thesis describes the structural analysis of O-polysaccharides from the Gram-negative bacterium Escherichia coli that is a diarrhoeal pathogen. The Escherichia coli serotypes investigated were O178, O171, O166 and O128. The methods used in these studies were nuclear magnetic resonance spectroscopy and component analysis.

    All analysed serotypes had pentasaccharide repeating units. E. coli strain O128 and O166 was shown to have the topology of four carbohydrate residues in the backbone while the 5-residue backbone is found in E. coli O178 and O171.

    The biological repeating units have been determined for the analysed polysaccharides and it was shown that all of the serotypes studied had a 3-substituted N-acetylgalactosamine residue at the reducing end. From this it was deduced that the terminal end of E. coli O171 and O128 have sialic acid and blood type antigens, respectively. This should make E. coli O171 and O128 less recognizable to the immune system as a foreign invader. This can result in that E. coli O171 and O128 may evade the immune system more easily.

  • 4.
    Ali, Tara
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Weintraub, Andrej
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Structural determination of the O-antigenic polysaccharide from Escherichia coli O1662007Inngår i: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 342, nr 2, s. 274-278Artikkel i tidsskrift (Fagfellevurdert)
  • 5. Arewång, Carl Johan
    et al.
    Lahmann, Martina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Oscarson, Stefan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Tidén, Anna-Karin
    Synthesis of urine drug metabolites: glucuronic acid glycosides of phenol intermediates2007Inngår i: Carbohydrate Research, ISSN 0008-6215, Vol. 342, nr 7, s. 970-974Artikkel i tidsskrift (Fagfellevurdert)
  • 6.
    Aydin, Juhanes
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Fine-tuning of the catalytic activity and selectivity of palladium pincer complexes2007Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis is focused on optimization of the catalytic properties of so-called pincer complexes. This work involved synthesis of a large variety of palladium pincer complexes, which were applied in various organic transformations. Optimization of the catalytic properties (also called fine-tuning) was directed to increase the catalytic activity as well as the chemo- and stereo-selectivity of the complexes. This could be achieved by varying the heteroatoms in the terdentate pincer ligand, by changing the electronic properties of the coordinated aryl moiety and by implementing chiral functionalities in the pincer complexes.

    In the cross-coupling reaction of vinyl epoxides and aziridines with organoboronic acids the chemoselectivity of the reaction could be increased by employment of pincer complexes instead of commonly used palladium(0) catalysts. Furthermore, application of a methoxy substituent in the aromatic subunit of the complex considerably increased the activity of the pincer complex catalyst.

    Fine-tuning of the stereoselectivity in electrophilic allylation reactions was achieved using a wide variety of BINOL and biphenanthrol based pincer complexes. The synthesis of these highly stable chiral palladium complexes was accomplished by using an efficient modular approach. The highest enantioselectivity (85% ee) was obtained by applying biphenanthrol based pincer complexes.

    We have presented the first palladium pincer complex catalyzed condensation of sulfonimines with isocyanoacetate. Variation of the heteroatoms in the terdentate ligand of the complex strongly influenced the stereoselectivity of the catalytic transformation. The highest stereoselectivity was obtained by using phosphine based pincer complexes. We have also succeeded to isolate and fully characterize the key intermediate of this reaction.

  • 7.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kumar, K. Senthil
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium pincer complex-catalyzed condensation of sulfonimines and isocyanoacetate to imidazoline derivatives. Dependence of the stereoselectivity on the ligand effects2007Inngår i: Advanced Synthesis & Catalysis, ISSN 1615-4150, Vol. 349, nr 17-18, s. 2585-2594Artikkel i tidsskrift (Fagfellevurdert)
  • 8.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kumar, K. Senthil
    Sayah, Mahmoud J.
    Wallner, Olov A.
    Szabó, Kálmán J.
    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 Trifluoroborate2007Inngår i: The Journal of Organic Chemistry, ISSN 0022-3263, Vol. 72, nr 13, s. 4689-4697Artikkel i tidsskrift (Fagfellevurdert)
  • 9.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Senthil, Kumar K
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sayah, Mahmoud J
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wallner, Olov A
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán J
    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.2007Inngår i: Journal of Organic Chemistry, Vol. 72, nr 13, s. 4689-4697Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    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.

  • 10.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wallner, Olov A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olsson, Vilhelm J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Application of BINOL based pincer-complexes for palladium-catalyzed transformations2007Inngår i: Abstracts of Papers, 233rd ACS National Meeting, Chicago, IL, United States, March 25-29, 2007, 2007Konferansepaper (Annet vitenskapelig)
  • 11.
    Aydin, Juhanes
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wallner, Olov A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olsson, Vilhelm J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium pincer complex catalyzed asymmetric transformations of sulfonimines2007Inngår i: Abstracts of Papers, 233rd ACS National Meeting, Chicago, IL, United States, March 25-29, 2007, 2007Konferansepaper (Annet vitenskapelig)
  • 12. Back, Marcus
    et al.
    Nyhlén, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kvarnström, Ingemar
    Rosenquist, Åsa
    Samuelsson, Bertil
    Design, synthesis and SAR of potent statin-based β-secretase inhibitors: Exploration of P1 phenoxy and benzyloxy residues2007Konferansepaper (Annet vitenskapelig)
  • 13. Berggren, Gustav
    et al.
    Kaynak, Filiz Betul
    Anderlund, Magnus F.
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Åkermark, Björn
    Institutionen för organisk kemi.
    Tetraethylammonium [12,12-diethyl-2,2,9,9-tetramethyl-1,4,7,10-tetraza-5,6-benzotridecane-3,8,11,13-tetra-one(4-)]oxidomanganate(V)2007Inngår i: Acta Crystallographica Section E, ISSN 1600-5368, Vol. E63, s. m2672-m2673Artikkel i tidsskrift (Fagfellevurdert)
  • 14. Berner, Simon
    et al.
    Lidbaum, Hans
    Ledung, Greger
    Åhlund, John
    Nilson, Katharina
    Schiessling, Joachim
    Gelius, Ulrik
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Puglia, Carla
    Oscarsson, Sven
    Electronic and structural studies of immobilized thiol-derivatized cobalt porphyrins on gold surfaces2007Inngår i: Applied Surface Science, ISSN 0169-4332, Vol. 253, nr 18, s. 7540-7548Artikkel i tidsskrift (Fagfellevurdert)
  • 15.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    High-Yielding One-Pot Synthesis of Diaryliodonium Triflates from Arenes and Iodine or Aryl Iodides2007Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, nr 24, s. 2521-2523Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Unsymmetric and symmetric diaryliodonium triflates are synthesized from both electron-deficient and electron-rich substrates in a fast, high yielding, and operationally simple protocol employing arenes and aryl iodides or iodine.

  • 16.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhu, Mingzhao
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient and General One-Pot Synthesis of Diaryliodonium Triflates: Optimization, Scope and Limitations2007Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 349, nr 17-18, s. 2610-2618Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Symmetrical and unsymmetrical diaryliodonium triflates have been synthesized from both electron-deficient and electron-rich arenes and aryl iodides with mCPBA and triflic acid. A thorough investigation of the optimization, scope and limitations has resulted in an improved one-pot protocol that is fast, high-yielding, and operationally simple. The reaction has been extended to the direct synthesis of symmetrical iodonium salts from iodine and arenes, conveniently circumventing the need for aryl iodides.

  • 17.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhu, Mingzhao
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient and general one-pot synthesis of diaryliodonium triflates: scope and limitations2007Inngår i: SIS Report: The 10th Symposium on Iodine Science, Chiba University, Japan 2007, 2007, s. 19-22Konferansepaper (Annet vitenskapelig)
  • 18.
    Bogár, Krisztián
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthetic Transformations via Metal- and Enzyme-Catalyzed Dynamic Kinetic Resolution2007Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis deals with the preparation of a new half-sandwich type ruthenium(II)- catalyst for racemization of optically active secondary alcohols and the development of a highly efficient method in combination with lipases such as Candida antarctica lipase B and Pseudomonas cepacia lipase for dynamic kinetic resolution of various functionalized alcohols under mild reaction conditions.

    It was shown that the RuCl(CO)25-C5Ph5) complex can racemize optically active aliphatic and aromatic secondary alcohols at room temperature in rather short times. Different parameters, such as the nature of the catalyst, catalyst loading and solvent effect were studied. After the optimization steps, the Ru-catalyzed racemization of (S)-1-phenylethanol in the presence of Candida antarctica lipase B was also investigated. The compatibility of the metal- and enzyme-catalyzed reactions led to a highly efficient coupled catalytic system for transformation of racemic alcohols to their enantiomerically pure acetates. This protocol was applied for a wide range of secondary alcohols. It was shown that in the case of allylic alcohols the obtained enantiopure allylic acetates are useful compounds for synthesis of α-methyl carboxylic acids such as (R)-Flurbiprofen and acyloin acetates. Highly selective dynamic kinetic asymmetric transformation of 3,5-piperidine diol to deliver various 3,5-dioxygenated piperidines is also described.

  • 19.
    Bogár, Krisztián
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    High-yielding metalloenzymatic dynamic kinetic resolution of fluorinated aryl alcohols2007Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 48, nr 31, s. 5471-5474Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dynamic kinetic resolution (DKR) of various fluorinated aryl alcohols by a combination of lipase-catalyzed enzymatic resolution with in situ ruthenium-catalyzed alcohol racemization is described. (R)-Selective Candida antarctica lipase B (CALB) was employed for transesterification of different fluoroaryl alcohols in DKR reactions delivering the corresponding acetates in high yield (97%) with excellent enantiomeric excess (98%).

  • 20.
    Bogár, Krisztián
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hoyos Vidal, Pilar
    Alcántara León, Andrés R.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chemoenzymatic Dynamic Kinetic Resolution of Allylic Alcohols: A Highly Enantioselective Route to Acyloin Acetates2007Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 9, nr 17, s. 3401-3404Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dynamic kinetic resolution (DKR) of a series of sterically hindered allylic alcohols has been conducted with Candida antarctica lipase B (CALB) and ruthenium catalyst 1. The optically pure allylic acetates obtained were subjected to oxidative cleavage to give the corresponding acylated acyloins in high yields without loss of chiral information.

  • 21. Bogár, Krisztián
    et al.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Large-scale ruthenium- and enzyme-catalyzed dynamic kinetic resolution of (rac)-1-phenylethanol2007Inngår i: Beilstein Journal of Organic Chemistry, ISSN 1860-5397, Vol. 3, s. artikel nr 50-Artikkel i tidsskrift (Fagfellevurdert)
  • 22. Bäck, Marcus
    et al.
    Johansson, Per-Ola
    Wångsell, Fredrik
    Thorstensson, Fredrik
    Kvarnström, Ingemar
    Ayesa, Susana
    Wähling, Horst
    Pelcman, Mikael
    Jansson, Katarina
    Lindström, Stefan
    Wallberg, Hans
    Classon, Björn
    Rydergård, Christina
    Vrang, Lotta
    Hamelink, Elizabeth
    Hallberg, Anders
    Rosenquist, Åsa
    Samuelsson, Bertil
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Novel potent macrocyclic inhibitors of the hepatitis C virus NS3 protease: use of cyclopentane and cyclopentene P2-motifs2007Inngår i: Bioorganic & Medicinal Chemistry, ISSN 0968-0896, Vol. 15, nr 22, s. 7184-7202Artikkel i tidsskrift (Fagfellevurdert)
  • 23.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. -.
    Asymmetric Catalysis via Dynamic Kinetic Resolution2007Inngår i: Asymmetric Synthesis - The Essentials, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim , 2007, s. 171-175Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    -

  • 24. Carballeira, José Daniel
    et al.
    Krumlinde, Patrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bocola, Marco
    Vogel, Andreas
    Reetz, Manfred T.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Directed evolution and axial chirality: optimization of the enantioselectivity of Pseudomonas aeruginosa lipase towards the kinetic resolution of a racemic allene2007Inngår i: Chemical Communications, ISSN 1359-7345, Vol. 20, s. 1913-1915Artikkel i tidsskrift (Fagfellevurdert)
  • 25. Castro, Vasco
    et al.
    Dvinskikh, Sergey V.
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sandström, Dick
    Maliniak, Arnold
    NMR studies of membranes composed of glycolipids and phospholipids2007Inngår i: Biochimica et Biophysica Acta, Vol. 1768, nr -, s. 2432-2437Artikkel i tidsskrift (Fagfellevurdert)
  • 26. Crovetto, Luis
    et al.
    Paredes, Jose M.
    Rios, Ramon
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Talavera, Eva M.
    Avarez-Pez, Jose M.
    Photophysics of a xanthenic derivative dye useful as an ""On/Off"" fluorescence probe2007Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 111, nr 51, s. 13311-13320Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The photophysical behavior of a new fluorescein derivative has been explored by using absorption and steady-state and time-resolved fluorescence measurements. The influence of ionic strength, as well as total buffer concentration, on both the absorbance and fluorescence has been investigated. The apparent acidity constant of the dye determined by absorbance is almost independent of the added buffer and salt concentrations. A semiempirical model is proposed to rationalize the variations in the apparent pK(a) values. The excited-state proton-exchange reaction around the physiological pH becomes reversible upon addition of phosphate buffer, inducing a pH-dependent change of the steady-state fluorescence and decay times. Fluorescence decay traces, collected as a function of total buffer concentration and pH, were analyzed by global compartmental analysis, yielding the following values of the rate constants describing excited-state dynamics: k(01) = 1.29 x 10(10) s(-1), k(02) = 4.21 x 10(8) s(-1), k(21)approximate to 3 x 10(6) M-1 s(-1), k(12)(B) = 6.40 x 10(8) M-1 s(-1), and k(21)(B) = 2.61 x 10(7) M-1 s(- 1). The decay rate constant values of k(01), k(21), and k(21)(B), along with the low molar absorption coefficient of the neutral form, mean that coupled decays are practically monoexponential at buffer concentrations higher than 0.02 M and any pH. Thus, the pH and buffer concentration can modulate the main lifetime of the dye.

  • 27.
    Cumpstey, Ian
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Eriksson, Lars
    Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Bis(methyl 2,4,6-tri-O-acetyl-beta-D-allofuranosid-3-yl)sulfane2007Inngår i: Acta Crystallographica Section E, ISSN 1600-5368, Vol. E63, s. o4197-Artikkel i tidsskrift (Fagfellevurdert)
  • 28.
    Dziedzic, Pawel
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Acyclic beta-amino acid catalyzed asymmetric anti-selective Mannich-type reactions2007Inngår i: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 18, nr 9, s. 1033-1037Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

     The ability of a primary amine containing acyclic beta(3)-amino acids to catalyze direct asymmetric anti-selective Mannich-type reactions is presented. The reactions are generally highly diastereo- and enantioselective to give the corresponding Mannich products with up to >19:1 dr (anti/syn) and 88-99% ee.

  • 29.
    Ekström, Jesper
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Transition Metal Hydrides: Biomimetic Studies and Catalytic Applications2007Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In this thesis, studies of the nature of different transition metal-hydride complexes are described. The first part deals with the enantioswitchable behaviour of rhodium complexes derived from amino acids, applied in asymmetric transfer hydrogenation of ketones. We found that the use of amino acid thio amide ligands resulted in the formation of the R-configured product, whereas the use of the corresponding hydroxamic acid- or hydrazide ligands selectively gave the S-alcohol.

    Structure/activity investigations revealed that the stereochemical outcome of the catalytic reaction depends on the ligand mode of coordination.

    In the second part, an Fe hydrogenase active site model complex with a labile amine ligand has been synthesized and studied. The aim of this study was to find a complex that efficiently catalyzes the reduction of protons to molecular hydrogen under mild conditions. We found that the amine ligand functions as a mimic of the loosely bound ligand which is part of the active site in the hydrogenase.

    Further, an Fe hydrogenase active site model complex has been coupled to a photosensitizer with the aim of achieving light induced hydrogen production. The redox properties of the produced complex are such that no electron transfer from the photosensitizer part to the Fe moiety occurs.

    In the last part of this thesis, the development of a protocol for the transfer hydrogenation of ketones to secondary alcohols without the involvement of transition metal catalysts is described. A variety of ketones were efficiently reduced in 2-propanol using catalytic amounts of alkali alkoxide under microwave irradiation.

  • 30.
    Ekström, Jesper
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wettergren, Jenny
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Adolfsson, Hans
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    A Simple and Efficient Catalytic Method for the Reduction of Ketones2007Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 349, nr 10, s. 1609-1613Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A range of ketones was efficiently reduced in the presence of catalytic amounts of lithium isopropoxide in 2-propanol under microwave heating, with alcohol products being formed in yields up to 99 %.

  • 31.
    Frigell, Jens
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Cumpstey, Ian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    First synthesis of 4a-carba-beta-D-galactofuranose2007Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 48, nr 52, s. 9073-9076Artikkel i tidsskrift (Fagfellevurdert)
  • 32.
    Färnbäck, Magnus
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Söderman, Peter
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Eriksson, Lars
    Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Methyl 3,4,6-tri-O-acetyl-2-deoxy-2-azido-alpha-D-galactopyranosyl-(1-2)-: [3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl-(1-3)]-4-O-benzoyl-alpha-L-rhamnopyranoside n-hexane 0.1-solvate2007Inngår i: Acta Crystallographica: Section E, Vol. E63, s. o1581-o1583Artikkel i tidsskrift (Fagfellevurdert)
  • 33.
    Fång, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljökemi.
    Eriksson, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljökemi.
    Bergman, Åke
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljökemi.
    Widmalm, Göran
    Institutionen för organisk kemi.
    Separation and NMR characterisation of Hexabromocyclododecane (HBCDD)2007Inngår i: Svensk-norsk miljökjemisk vintermöte: Dr. Holms Hotell, Geilo, 2007, s. 34-Konferansepaper (Annet vitenskapelig)
  • 34. Gao, Weiming
    et al.
    Ekström, Jesper
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liu, Jianhui
    Chen, Changneng
    Eriksson, Lars
    Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Weng, Linhong
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    Binuclear iron-sulfur complexes with bidentate phosphine ligands as active site models of Fe-hydrogenase and their catalytic proton reduction2007Inngår i: Inorganic Chemistry, ISSN 0020-1669, Vol. 46, nr 6, s. 1981-1991Artikkel i tidsskrift (Fagfellevurdert)
  • 35. Gao, Weiming
    et al.
    Liu, Jianhui
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    Facile and highly efficient light-induced PR3/CO ligand exchange: a novel approach to the synthesis of [(mu-SCH2NnPrCH2S)Fe2(CO)4(PR3)2]2007Inngår i: Journal of Organometallic Chemistry, ISSN 0022-328X, Vol. 692, s. 1579-1583Artikkel i tidsskrift (Fagfellevurdert)
  • 36.
    Gao, Yan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Liu, Jianhui
    Jiang, Wenfeng
    Xia, Ming
    Zhang, Wei
    Li, Minna
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    Synthesis and photophysical and electrochemical properties of a binuclear Ru(bpy)3-Cu(III) corrole complex2007Inngår i: Journal of Porphyrins and Phthalocyanines, ISSN 1088-4246, Vol. 11, nr 5-6, s. 463-469Artikkel i tidsskrift (Fagfellevurdert)
  • 37. Gao, Yan
    et al.
    Liu, Jianhui
    Na, Yong
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    Synthesis and characterization of manganese and copper corrole xanthene complexes as catalysts for water oxidation2007Inngår i: Tetrahedron, ISSN 0040-4020, Vol. 63, nr 9, s. 1987-1994Artikkel i tidsskrift (Fagfellevurdert)
  • 38. Hafrén, Jonas
    et al.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Direct Bronsted acid-catalyzed derivatization of cellulose with poly(L-lactic acid) and D-mandelic acid2007Inngår i: Nordic Pulp and Paper Research Journal, ISSN 0283-2631, Vol. 22, nr 2, s. 184-187Artikkel i tidsskrift (Fagfellevurdert)
  • 39. Hafrén, Jonas F.
    et al.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Modification of substrates bearing amino and alcohol groups2007Patent (Annet (populærvitenskap, debatt, mm))
  • 40. Hakkarainen, Birgit
    et al.
    Kenne, Lennart
    Lahmann, Martina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Oscarson, Stefan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sandström, Corine
    Spectral assignments and reference data: NMR study of hydroxy protons of di- and trimannosides, substructures of Man-92007Inngår i: Magnetic Resonance in Chemistry, ISSN 0749-1581, Vol. 45, nr 12, s. 1076-1080Artikkel i tidsskrift (Fagfellevurdert)
  • 41.
    Hiresova, Renata
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nucleoside H-phosphonates, XXII: Synthesis and properties of new nucleotide analogues - H-phosphonothiolate diesters2007Inngår i: Synlett, ISSN 0936-5214, nr 17, s. 2748-2752Artikkel i tidsskrift (Fagfellevurdert)
  • 42.
    Híresová, Renáta
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Studies on the condensation of H-phosphonate monoesters with S-Nucleophiles2007Inngår i: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Konferansepaper (Annet vitenskapelig)
  • 43.
    Ibrahem, Ismail
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Development of organocatalytic asymmetric transformations2007Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The ability of amino acids and amino acid derivatives to mediate various organocatalytic asymmetric transformations has been investigated and applied in the development of various reactions. This work describes the development of a direct catalytic asymmetric α-aminomethylation of ketones and aldehydes, a catalytic asymmetric aziridination, hydrophosphination and amination of α,β-unsaturated aldehydes.

  • 44.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramon
    Vesely, Jan
    Hammar, Peter
    Eriksson, Lars
    Himo, Fahmi
    Cordova, Armando
    Enantioselective Organocatalytic Hydrophosphination of α,β- Unsaturated Aldehydes2007Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 46, s. 4507-Artikkel i tidsskrift (Fagfellevurdert)
  • 45.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramon
    Vesely, Jan
    Zhao, Guiling
    Cordova, Armando
    Organocatalytic Asymmetric 5-Hydroxyisoxazolidine Synthesis: A Highly Enantioselective Route to β-Amino Acids2007Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, s. 849-852Artikkel i tidsskrift (Fagfellevurdert)
  • 46.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramón
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vesely, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantioselective organocatalytic hydrophosphination of alpha,beta-unsaturated aldehydes2007Inngår i: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Konferansepaper (Annet vitenskapelig)
  • 47.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramón
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vesely, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Organocatalytic asymmetric multi-component [C+NC+CC] synthesis of highly functionalized pyrrolidine derivatives2007Inngår i: Tetrahedron Letters, ISSN 0040-4039, Vol. 48, nr 36, s. 6252-6257Artikkel i tidsskrift (Fagfellevurdert)
  • 48.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramón
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vesely, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hammar, Peter
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Himo, Fahmi
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantioselective organocatalytic hydrophosphination of alpha,beta-unsaturated aldehydes2007Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 46, s. 4507-4510Artikkel i tidsskrift (Fagfellevurdert)
  • 49.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramón
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vesely, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhao, Gui-Ling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Catalytic enantioselective 5-hydroxyisoxazolidine synthesis: an asymmetric entry to beta-amino acids2007Inngår i: Synthesis, ISSN 0039-7881, nr 7, s. 1153-1157Artikkel i tidsskrift (Fagfellevurdert)
  • 50.
    Ibrahem, Ismail
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rios, Ramón
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vesely, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhao, Gui-Ling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Córdova, Armando
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Organocatalytic asymmetric 5-hydroxyisoxazolidine synthesis: a highly enantioselective route to beta-amino acids2007Inngår i: Chemical Communications, s. 849-851Artikkel i tidsskrift (Fagfellevurdert)
123 1 - 50 of 140
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