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  • 301.
    Franzén, Johan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Löfstedt, Joakim
    Falk, Jennica
    Bäckvall, Jan-E
    Stereoselective Palladium-Catalyzed Carbocyclization of Allenic Allylic Carboxylates.2003Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 125, nr 46, s. 14140-14148Artikkel i tidsskrift (Fagfellevurdert)
  • 302. François, Camille
    et al.
    Pourchet, Sylvie
    Boni, Gilles
    Rautiainen, Sari
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Samec, Joseph
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Fournier, Lucie
    Robert, Carine
    Thomas, Christophe M.
    Fontaine, Stephane
    Gaillard, Yves
    Placet, Vincent
    Plasseraud, Laurent
    Design and synthesis of biobased epoxy thermosets from biorenewable resources2017Inngår i: Comptes rendus. Chimie, ISSN 1631-0748, E-ISSN 1878-1543, Vol. 20, nr 11-12, s. 1006-1016Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biobased diepoxy synthons derived from isoeugenol, eugenol or resorcinol (DGE-isoEu, DGE-Eu and DGER, respectively) have been used as epoxy monomers in replacement of the diglycidyl ether of bisphenol A (DGEBA). Their curing with six different biobased anhydride hardeners leads to fully biobased epoxy thermosets. These materials exhibit interesting thermal and mechanical properties comparable to those obtained with conventional petrosourced DGEBA-based epoxy resins cured in similar conditions. In particular, a high T-g in the range of 90-130 degrees C and instantaneous moduli higher than 4.3 GPa have been recorded. These good performances are very encouraging, making these new fully biobased epoxy thermosets compatible with the usual structural application of epoxy materials.

  • 303.
    Frigell, Jens
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Cumpstey, Ian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Carbasugar analogues of galactofuranosides: alpha-O-linked derivatives2010Inngår i: BEILSTEIN J ORG CHEM, ISSN 1860-5397, Vol. 6, s. 1127-1131Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Using an indirect method, we have synthesised alpha-linked carbasugar analogues of galactofuranosides for the first time. Ring opening of a beta-talo configured carbasugar 1,2-epoxide by alcohol nucleophiles under Lewis acidic conditions proceeded with very good regioselectivity to give alpha-talo configured C1-substituted ethers with a free OH-group at the C2 position. Inversion of configuration at C2 by an oxidation-reduction sequence gave the alpha-galacto configured carbahexofuranose C1 ethers. A carbadisaccharide corresponding to the Galf(alpha 1 -> 3)Manp substructure from Apodus deciduus galactomannan was synthesised to exemplify the method.

  • 304.
    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)
  • 305.
    Frigell, Jens
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Cumpstey, Ian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of carbadisaccharide mimics of galactofuranosides2009Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 50, nr 36, s. 5142-5144Artikkel i tidsskrift (Fagfellevurdert)
  • 306.
    Frigell, Jens
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Cumpstey, Ian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Carbasugar analogues of galactofuranosides: beta-O-linked derivatives and towards beta-S-linked derivatives2011Inngår i: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 346, nr 11, s. 1277-1290Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A selectively protected carbasugar analogue of beta-galactofuranose was synthesised from glucose using ring-closing metathesis as the key step. The carbasugar was converted into an alpha-galacto configured 1,2-epoxide, which was an effective electrophile in Lewis acid catalysed coupling reactions with alcohols. The epoxide was opened with regioselective attack at C-1 to give beta-galacto configured C-1 ethers. Using carbohydrates as nucleophiles, we synthesised a number of pseudodisaccharides. The epoxide was also regioselectively opened at C-1 with a sulfur nucleophile under basic conditions to give a beta-galacto configured C-1 thioether.

  • 307.
    Frigell, Jens
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pearcey, Jean A.
    Lowary, Todd L.
    Cumpstey, Ian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Carbasugar Analogues of Galactofuranosides: Pseudodisaccharide Mimics of Fragments of Mycobacterial Arabinogalactan2011Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 7, s. 1367-1375Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A partially protected carbasugar analogue of beta-galactofuranose was converted into an alpha-galacto-configured 1,2-epoxide, which was opened by alcohols under Lewis acid catalysis with regioselective attack at C-1 to give beta-galacto-configured C-1 ethers. Using OH-5 and OH-6 carbagalactofuranose derivatives as nucleophiles, we synthesised pseudodisaccharide analogues of substructures of the arabinogalactan from M. tuberculosis. The dicarba analogue of the disaccharide Galf(beta 1 -> 5) Galf was found to moderately inhibit the action of GlfT2 galactofuranosyl transferase from M. tuberculosis.

  • 308.
    Fryxelius, Jacob
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Eilers, Gerriet
    Feyziyev, Yashar
    Magnuson, Ann
    Sun, Licheng
    Lomoth, Reiner
    Synthesis and redox properties of a [meso-tris(4-nitrophenyl)corrolato]Mn(III) complex2005Inngår i: Journal of Porphyrins and Phtalocyanines, Vol. 9, s. 379-386Artikkel i tidsskrift (Fagfellevurdert)
  • 309.
    Fryxelius, Jacob
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pica, Delphine
    Eriksson, Lars
    Åkermark, Björn
    Preparation of Copper(II) Complexes of a Mixed Amide-Phenolate LigandInngår i: Inorganic Chemistry CommunicationsArtikkel i tidsskrift (Fagfellevurdert)
  • 310.
    Färnbäck, Magnus
    et al.
    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 2-O-beta-L-fucopyranosyl alpha-D-glucopyranoside monohydrate: a synchrotron study2008Inngår i: Acta Crystallographica Section C, ISSN 0108-2701, Vol. 64, nr 2, s. o31-o32Artikkel i tidsskrift (Fagfellevurdert)
  • 311.
    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)
  • 312. Gagliardo, Marcella
    et al.
    Selander, Nicklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mehendale, Nilesh C.
    van Koten, Gerard
    Klein Gebbink, Robertus J. M.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Catalytic performance of symmetrical and unsymmetrical sulfur-containing pincer complexes: synthesis and tandem catalytic activity of the first PCS-pincer palladium complex2008Inngår i: Chemistry: a European journal, ISSN 0947-6539, Vol. 14, nr 16, s. 4800-4809Artikkel i tidsskrift (Fagfellevurdert)
  • 313.
    Galkin, Maxim V.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Smit, Arjan T.
    Subbotina, Elena
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Artemenko, Konstantin A.
    Bergquist, Jonas
    Huijgen, Wouter J. J.
    Samec, Joseph S. M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hydrogen-free catalytic fractionation of woody biomass2016Inngår i: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 9, nr 23, s. 3280-3287Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The pulping industry could become a biorefinery if the lignin and hemicellulose components of the lignocellulose are valorized. Conversion of lignin into well-defined aromatic chemicals is still a major challenge. Lignin depolymerization reactions often occur in parallel with irreversible condensation reactions of the formed fragments. Here, we describe a strategy that markedly suppresses the undesired condensation pathways and allows to selectively transform lignin into a few aromatic compounds. Notably, applying this strategy to woody biomass at organosolv pulping conditions, the hemicellulose, cellulose, and lignin were separated and in parallel the lignin was transformed into aromatic monomers. In addition, we were able to utilize a part of the lignocellulose as an internal source of hydrogen for the reductive lignin transformations. We hope that the presented methodology will inspire researchers in the field of lignin valorization as well as pulp producers to develop more efficient biomass fractionation processes in the future.

  • 314. 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)
  • 315. Gao, Weiming
    et al.
    Liu, Jianhui
    Jiang, Weina
    Wang, Mei
    Weng, Linhong
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    An azadithiolate bridged Fe2S2 complex as active site model of FeFe-hydrogenase covalently linked to a Re(CO)3(bpy)(py) photosensitizer aiming for light-driven hydrogen production2008Inngår i: Comptes Rendus Chimie, ISSN 1631-0748, Vol. 11, nr 8, s. 915-921Artikkel i tidsskrift (Fagfellevurdert)
  • 316. Gao, Weiming
    et al.
    Liu, Jianhui
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    Bidentate phosphine ligand based Fe2S2-containing macromolecules: synthesis, characterization, and catalytic electrochemical hydrogen production2006Inngår i: Inorganic Chemistry, ISSN 0020-1669, Vol. 45, nr 23, s. 9169-9171Artikkel i tidsskrift (Fagfellevurdert)
  • 317. 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)
  • 318.
    Gao, Weiming
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Junliang
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Li, Mingrun
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Åkermark, Torbjörn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Romare, Kristina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Licheng
    Royal Institute of Technology (KTH), Department of Organic Chemistry.
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of a [3Fe2S] cluster with low redox potential from [2Fe2S] hydrogenase models: electrochemical and photochemical generation of hydrogen2011Inngår i: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, Vol. 2011, nr 7, s. 1100-1105Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the attempted replacement of carbon monoxide by the bis(phosphane) dppv in a dinuclear [2Fe2S] complex, a trinuclear [3Fe2S] complex with two bis(phosphane) ligands was unexpectedly obtained. On protonation, this gave a bridged hydride complex with an unusually low potential for the reduction of protons to molecular hydrogen. The redox potential also appears sufficiently positive for direct electron transfer from an excited [Ru(bpy)(3)](2+) sensitizer.

  • 319.
    Gao, Weiming
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Junliang
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi, Avdelningen för strukturkemi.
    Åkermark, Torbjörn
    Li, Mingrun
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi, Avdelningen för strukturkemi.
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi, Avdelningen för strukturkemi.
    Sun, Licheng
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Attachment of a hydrogen-bonding carboxylate side chain to an [FeFe]-hydrogenase model complex: Influence on the catalytic mechanism2010Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 16, nr 8, s. 2537-2546Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Azapropanedithiolate (adt)-bridged model complexes of [FeFe]-hydrogenase bearing a carboxylic acid functionality have been designed with the aim of decreasing the potential for reduction of protons to hydrogen. Protonation of the bisphosphine complexes 46 has been studied by in situ IR and NMR spectroscopy, which revealed that protonation with triflic acid most likely takes place first at the N-bridge for complex 4 but at the FeFe bond for complexes 5 and 6. Using an excess of acid, the diprotonated species could also be observed, but none of the protonated species was sufficiently stable to be isolated in a pure state. Electrochemical studies have provided an insight into the catalytic mechanisms under strongly acidic conditions, and have also shown that complexes 3 and 6 are electro-active in aqueous solution even in the absence of acid, presumably due to hydrogen bonding. Hydrogen evolution, driven by visible light, has been observed for three-component systems consisting of [Ru(bpy)3]2+, complex 1, 2, or 3, and ascorbic acid in CH3CN/D2O solution by on-line mass spectrometry.

  • 320.
    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)
  • 321. 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)
  • 322.
    Gao, Yan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Åkermark, Torbjörn
    Liu, Jianhui
    Sun, Licheng
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nucleophilic attack of hydroxide on a MnV oxo complex: a model of the O-O bond formation in the oxygen evolving complex of photosystem II2009Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 131, nr 25, s. 8726-8727Artikkel i tidsskrift (Fagfellevurdert)
  • 323.
    Gemma, Emiliano
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Lahmann, Martina
    Oscarson, Stefan
    Synthesis of the tetrasaccharide α-D-Glcp-(1→3)-α-D-Manp-(1→2)-α-D-Manp-(1→2)-α-D-Manp recognised by Calreticulin/Calnexin2005Inngår i: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 340, nr 16, s. 2558-2562Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The title compound as its methyl glycoside was efficiently synthesized using a block synthesis approach. Halide-assisted glycosidations between 6-O-acetyl-2,3,4-tri-O-benzyl-α-d-glucopyranosyl iodide and ethyl 2-O-acetyl-4,6-di-O-benzyl-1-thio-α-d-mannopyranoside using triphenylphosphine oxide as promoter yielded, with complete α-selectivity, a disaccharide building block in high yield. The perbenzylated derivative of this proved to be an excellent donor affording 88% of the protected target tetrasaccharide in an NIS/AgOTf-promoted coupling to a known methyl dimannoside acceptor. Deprotection through catalytic hydrogenolysis then gave the target compound in 47% overall yield.

  • 324. George, Riham F.
    et al.
    Ismail, Nasser S. M.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Girgis, Adel S.
    Design, synthesis and QSAR studies of dispiroindole derivatives as new antiproliferative agents2013Inngår i: European Journal of Medicinal Chemistry, ISSN 0223-5234, E-ISSN 1768-3254, Vol. 68, s. 339-351Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A variety of 4'-ary1-3-(arylmethylidene)-1 ''-[(cyclic-amino)methylene]-1'-methyl-dispiro[cyclohexane-1,3'-pyrrolidine-2',3 ''-[3H]indole]-2,2 ''(1H)-diones 4a-u were prepared via reaction of 2E,6E-bis(arylidene)-1-cyclohexanones 1a-i with azomethine ylides, generated in situ via a decarboxylative condensation of isatins 2a-c and sarcosine (3). Single crystal X-ray study of 4a, revealed structural and stereochemical features of these derivatives. While most of the synthesized compounds exhibit mild antitumor properties when tested against various human tumor cell lines (HEPG2 liver, HELA cervical and PD prostate cancers), three of them, 4d and 4p (active against HEPG2), and compound 4g (active against HELA), demonstrated higher activities, that were close or even higher than that of the reference standard Doxorubicin. QSAR studies revealed good predictive and statistically significant 3 descriptor models (r(2) = 0.903-0.812, r(adjusted)(2) = 0.855-0.672, r(prediction)(2) = 0.773-0.605).

  • 325.
    Georgieva, Polina
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Quantum chemical modeling of enzymatic reactions: The Case of histone lysine methyltransferase2010Inngår i: Journal of Computational Chemistry, ISSN 0192-8651, E-ISSN 1096-987X, Vol. 31, nr 8, s. 1707-1714Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Quantum chemical cluster models of enzyme active sites are today an important and powerful tool in the study of various aspects of enzymatic reactivity. This methodology has been applied to a wide spectrum of reactions and many important mechanistic problems have been solved. Herein, we report a systematic study of the reaction mechanism of the histone lysine methyltransferase (HKMT) SET7/9 enzyme, which catalyzes the methylation of the N-terminal histone tail of the chromatin structure. In this study, HKMT SET7/9 serves as a representative case to examine the modeling approach for the important class of methyl transfer enzymes. Active site models of different sizes are used to evaluate the methodology. In particular, the dependence of the calculated energies on the model size, the influence of the dielectric medium, and the particular choice of the dielectric constant are discussed. In addition, we examine the validity of some technical aspects, such as geometry optimization in solvent or with a large basis set, and the use of different density functional methods.

  • 326. Georgieva, Polina
    et al.
    Wu, Qian
    McLeish, Michael J.
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    The reaction mechanism of phenylethanolamine N-methyltransferase: A density functional theory study2009Inngår i: Biochimica et Biophysica Acta, ISSN 0006-3002, E-ISSN 1878-2434, Vol. 1794, nr 12, s. 1831-1837Artikkel i tidsskrift (Fagfellevurdert)
  • 327. Ghanem, Raed
    et al.
    Xu, Yunhua
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    pan, Jie
    Hoffmann, Tobias
    Andersson, Johan
    Polivka, Tomas
    Pascher, Torbjörn
    Styring, Stenbjörn
    Sun, Licheng
    Sundström, Villy
    Light-driven Tyrosine Radical Formation in a Ruthenium-Tyrosine Complex Attached to Nanoparticle TiO22002Inngår i: Inorganic Chemistry, ISSN 0020-1669, Vol. 41, nr 24, s. 6258-6266Artikkel i tidsskrift (Fagfellevurdert)
  • 328. Ghobril, Cynthia
    et al.
    Hammar, Peter
    Kodepelly, Sanjeevarao
    Spiess, Bernard
    Wagner, Alain
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Baati, Rachid
    Structure-Reactivity Relationship Studies for Guanidine-Organocatalyzed Direct Intramolecular Aldolization of Ketoaldehydes2010Inngår i: ChemCatChem, ISSN 1867-3880, E-ISSN 1867-3899, Vol. 2, nr 12, s. 1573-1581Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Structure-reactivity studies are performed to explore the reaction mechanism of the guanidine-catalyzed intramolecular aldol reaction of ketoaldehydes. A large number of guanidine and guanidine-like catalysts are synthesized and their properties studied. Kinetic profiles and pK(a) values of the catalysts are measured and correlated to reaction barriers calculated using density functional theory (DFT). The DFT calculations show that structural rigidity influences the pKa of the guanidines. Although the basicity is a very important factor in the catalysis, it is not sufficient to fully account for its catalytic efficiency. The availability of two aligned nitrogen reaction sites for proton shuttling in the transition state is an essential feature that helps to rationalize the reactivity pattern and the activation mode for this family of organocatalysts.

  • 329.
    Ghosh, Raju
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Lindstedt, Erik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jalalian, Nazli
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Room Temperature, Metal-Free Arylation of Aliphatic Alcohols2014Inngår i: ChemistryOpen, ISSN 2191-1363, Vol. 3, nr 2, s. 54-57Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diaryliodonium salts are demonstrated as efficient arylating agents of aliphatic alcohols under metal-free conditions. The reaction proceeds at room temperature within 90min to give alkyl aryl ethers in good to excellent yields. Aryl groups with electron-withdrawing substituents are transferred most efficiently, and unsymmetric iodonium salts give chemoselective arylations. The methodology has been applied to the formal synthesis of butoxycaine.

  • 330.
    Ghosh, Raju
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Metal-Free Synthesis of N-Aryloxyimides and Aryloxyamines2014Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, nr 6, s. 1830-1832Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    N-Hydroxyphthalimide and N-hydroxysuccinimide have been arylated with diaryliodonium salts to provide N-aryloxyimides in excellent yields in short reaction times. A novel hydrolysis under mild and hydrazine-free conditions yielded aryloxyamines, which are valuable building blocks in the synthesis of oxime ethers and benzofurans.

  • 331.
    Ghosh, Raju
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stridfeldt, Elin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Metal-Free One-Pot Synthesis of Benzofurans2014Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 20, nr 29, s. 8888-8892Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ethyl acetohydroxamate was efficiently arylated with diaryliodonium salts at room temperature under transition-metal-free conditions. The obtained O-arylated products were reacted in situ with ketones under acidic conditions to yield substituted benzo[b]furans through oxime formation, [3,3]-rearrangement, and cyclization in a fast and operationally simple one-pot fashion without using excess reagents. Alternatively, the O-arylated products could be isolated or transformed in situ to aryloxyamines or O-arylaldoximes. The methodology was applied to the synthesis of Stemofuran A and the formal syntheses of Coumestan, Eupomatenoid 6, and (+)-machaeriol B.

  • 332.
    Gigant, Nicolas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of Conjugated Dienes via a Biomimetic Aerobic Oxidative Coupling of Two CvinylH Bonds2013Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 19, nr 33, s. 10799-10803Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A time to dienes: A highly efficient and general method has been developed to prepare conjugated dienes through a biomimetic approach. This aerobic oxidative coupling, involving two CvinylH bonds, proceeds under low Pd catalyst loading and employs catalytic amounts of p-benzoquinone and iron phthalocyanine as electron-transfer mediators (ETMs) under ambient oxygen pressure (see scheme).

  • 333.
    Gigant, Nicolas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Access to Cinnamyl Derivatives from Arenes and Allyl Esters by a Biomimetic Aerobic Oxidative Dehydrogenative Coupling2014Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, nr 6, s. 1664-1667Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient biomimetic aerobic oxidative dehydrogenative alkenylation of arenes with allyl esters is presented. The reaction proceeds under an ambient pressure of oxygen with relatively low catalyst loading of palladium acetate, employing catalytic amounts of electron-transfer mediators (ETMs). This study represents a new environmentally friendly method for the synthesis of cinnamyl derivatives.

  • 334.
    Gigant, Nicolas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Aerobic Direct C-H Arylation of Nonbiased Olefins2014Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, nr 17, s. 4432-4435Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient ligand-promoted biomimetic aerobic oxidative dehydrogenative cross-coupling between arenes and nonbiased olefins is presented. Acridine as a ligand was found to significantly enhance the rate, the yield, and the scope of the reaction under ambient oxygen pressure, providing a variety of alkenylarenes via an environmentally friendly procedure.

  • 335.
    Gigant, Nicolas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Aerobic Double Dehydrogenative Cross Coupling between Cyclic Saturated Ketones and Simple Arenes2014Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 20, nr 20, s. 5890-5894Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The synthesis of 3-aryl-2-cyclohexenones is a topic of current interest as they are not only privileged structures in bioactive molecules, but they are also relevant feedstocks for the synthesis of substituted phenols or anilines, which are ubiquitous structural elements both in drug design and medicinal chemistry. A simple and sustainable one-pot aerobic double dehydrogenative reaction under mild conditions for the introduction of arenes in the -position of cyclic ketones has been developed. Starting from the corresponding saturated ketone, this reaction sequence proceeds under relatively low Pd catalyst loading and involves catalytic amounts of electron-transfer mediators (ETMs) under ambient oxygen pressure.

  • 336.
    Gigant, Nicolas
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Université Paris-Sud, France.
    Quintin, Francois
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Preparation of Tetrasubstituted Olefins Using Mono or Double Aerobic Direct C-H Functionalization Strategies: Importance of Steric Effects2015Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 80, nr 5, s. 2796-2803Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A novel protocol for the synthesis of tetrasubstituted olefins through a biomimetic approach has been explored. Both mono- and diarylations were performed under ambient oxygen pressure, giving a range of highly hindered tetrasubstituted alkenes. For diarylation of disubstituted substrates, it was demonstrated that the second arylation is the rate-limiting step of the overall transformation.

  • 337. Girgis, Adel S.
    et al.
    Mabied, Ahmed F.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hegazy, Lamees
    George, Riham F.
    Farag, Hanaa
    Shalaby, ElSayed M.
    Farag, I. S. Ahmed
    Synthesis and DFT studies of an antitumor active spiro-oxindole2015Inngår i: New Journal of Chemistry, ISSN 1144-0546, E-ISSN 1369-9261, Vol. 39, nr 10, s. 8017-8027Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An anti-oncological active spiro-oxindole 7 was synthesized regioselectively via a [3+2]-cycloaddition reaction of azomethine ylide to exocyclic olefinic linkage of 4-piperidone 6, exhibiting properties against diverse tumor cell lines including leukemia, melanoma and cancers of the lung, colon, brain, ovary, breast, prostate, and kidney. Compound 7 crystallizes in the monoclinic system and P21/c space group with four molecules in the unit cell. The structure was also studied by AM1, PM3 and DFT techniques. DFT studies support the stereochemical selectivity of the reaction and determine the molecular electrostatic potential and frontier molecular orbitals.

  • 338. Girgis, Adel S.
    et al.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ismail, Nasser S. M.
    Farag, Hanaa
    Synthesis and QSAR study of novel cytotoxic spiro[3H-indole-3,2 '(1 ' H)-pyrrolo[3,4-c]pyrrole]-2,3 ',5 '(1H,2 ' aH,4 ' H)-triones2012Inngår i: European Journal of Medicinal Chemistry, ISSN 0223-5234, E-ISSN 1768-3254, Vol. 47, s. 312-322Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    1,3-Dipolar cycloaddition reaction of 1-aryl-1H-pyrrole-2,5-diones 1a-e with non-stabilized azomethine ylides, generated in situ via decarboxylative condensation of isatins 2a-c and sarcosine (3) in refluxing ethanol, afforded 4'-aryl-5'a,6'-dihydro-1'-methyl-spiro[3H-indole-3,2'(1 ' H)-pyrrolo[3,4-c]pyrrole]-2,3',5'(1H,2'aH,4'H)-triones 4a-o in good yields. Compound 4I exhibited high anti-tumor activity against HEPG2 (liver cancer) cell line (IC50 = 12.16 mu M) compared to that of Doxorubicin (IC50= 7.36 mu M), and the other synthesized compounds revealed moderate anti-tumor properties against HCT116 (colon), MCF7 (breast) and HEPG2 (liver) human tumor cell lines. 3D-Pharmacophore modeling and quantitative structure-activity relationship (QSAR) analysis were combined to explore the structural requirements controlling the observed anti-tumor properties. It was found that the major structural factors affecting potency of these compounds were related to their basic skeleton.

  • 339. Godefroid, Marie
    et al.
    Svensson, Mona V
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Cambier, Pierre
    Uzureau, Sophie
    Mirabella, Aurélie
    De Bolle, Xavier
    Van Cutsem, Pierre
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Letesson, Jean-Jacques
    Brucella melitensis 16M produces a mannan and other extracellular matrix components typical of a biofilm2010Inngår i: FEMS Immunology and Medical Microbiology, ISSN 0928-8244, E-ISSN 1574-695X, Vol. 59, nr 3, s. 364-377Artikkel i tidsskrift (Fagfellevurdert)
  • 340.
    Goncalves, Sylvie
    et al.
    Universite de Strasbourg, Faculte de Pharmacie UMR/CNRS 7199, Laboratoire des Systemes Chimiques Fonctionnels, Illkirch, France.
    Santoro, Stefano
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nicolas, Marc
    Les Laboratoires Pierre Fabre, Centre de Developpement Chimique et Industriel, Gaillac, France.
    Wagner, Alain
    Universite de Strasbourg, Faculte de Pharmacie UMR/CNRS 7199, Laboratoire des Systemes Chimiques Fonctionnels, Illkirch, France.
    Maillos, Philippe
    Les Laboratoires Pierre Fabre, Centre de Developpement Chimique et Industriel, Gaillac, France.
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Baati, Rachid
    Universite de Strasbourg, Faculte de Pharmacie UMR/CNRS 7199, Laboratoire des Systemes Chimiques Fonctionnels, Illkirch, France.
    Cationic cyclization of 2-alkenyl-1,3-dithiolanes: DiastereoselectiveSynthesis of trans-decalins2011Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 76, nr 9, s. 3274-3285Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An unprecedented and highly diastereoselective 6-endo-trig cyclization of 2-alkenyl-1,3-dithiolanes has beendeveloped yielding trans-decalins, an important scaffold present in numerous di- and triterpenes. The novelty of this 6-endo-trigc yclization stands in the stepwise mechanism involving 2-alkenyl-1,3-dithiolane, acting as a novel latent initiator. It is suggested that the thioketal opens temporarily under the influence of TMSOTf, triggering the cationic 6-endo-trig cyclization, andcloses after C−C bond formation and diastereoselective protonation to terminate the process. DFT calculations confirm this mechanistic proposal and provide a rationale for the observed diastereoselectivity. The reaction tolerates a wide range of functionalities and nucleophilic partners within the substrate. We have also shown that the one-pot 6-endo-trig cyclization followedby in situ 1,3-dithiolane deprotection afford directly the corresponding ketone. This improvement allowed the achievement of the shortest total synthesis of triptophenolide and the shortest formal synthesis of triptolide.

  • 341. González, David
    et al.
    Grilló, María-Jesús
    De Miguel, María-Jesús
    Ali, Tara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Arce-Gorvel, Vilma
    Delrue, Rose-May
    Conde-Álvarez, Raquel
    Munoz, Pilar
    López-Goni, Ignacio
    Iriarte, Maite
    Marín, Clara-M.
    Weintraub, Andrej
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zygmunt, Michel
    Letesson, Jean-Jacques
    Gorvel, Jean-Pierre
    Blasco, José-María
    Moriyón, Ignacio
    Brucellosis vaccines: assessment of Brucella melitensis lipopolysaccharide rough mutants defective in core and O-polysaccharide synthesis and export2008Inngår i: PLoS ONE, ISSN 1932-6203, Vol. 3, nr 7, s. e2760 (1-15)Artikkel i tidsskrift (Fagfellevurdert)
  • 342.
    González Miera, Greco
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nonclassical cyclodehydration of diols assisted by metal-ligand cooperation2017Artikkel i tidsskrift (Fagfellevurdert)
  • 343.
    González Miera, Greco
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bermejo Gómez, Antonio
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chupas, Peter J.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chapman, Karena W.
    Platero-Prats, Ana E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Topological Transformation of a Metal–Organic Framework Triggered by Ligand Exchange2017Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 56, nr 8, s. 4576-4583Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here we describe the topological transformation of the pores of a new framework in the bio-MOF-100 family (dia-c) into the known isomer (lcs) by doubling the pore volume, which occurs during postsynthesis modifications. During this transformation, reassembling of the metal–organic framework (MOF) building blocks into a completely different framework occurs, involving breaking/forming of metal–ligand bonds. MOF crystallinity and local structure are retained, as determined by powder X-ray diffraction (PXRD) and pair distribution function (PDF) analyses, respectively. We exploited the inherent dynamism of bio-MOF-100 by coupling chemical decorations of the framework using solvent-assisted ligand exchange to the topological change. Following this method and starting from the pristine dense dia-c phase, open lcs-bio-MOF-100 was prepared and functionalized in situ with an iridium complex (IrL). Alternatively, the dia-c MOF could be modified with wide-ranging amounts of IrL up to ca. 50 mol %, as determined by solution 1H NMR spectroscopy, by tuning the concentration of the solutions used and with no evidence for isomer transformation. The single-site nature of the iridium complexes within the MOFs was assessed by X-ray absorption spectroscopy (XAS) and PDF analyses. Ligand exchanges occurred quantitatively at room temperature, with no need of excess of the iridium metallolinker.

  • 344.
    González Miera, Greco
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    López, Aitor Bermejo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martínez-Castro, Elisa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Norrby, Per-Ola
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nonclassical Mechanism in the Cyclodehydration of Diols Catalyzed by a Bifunctional Iridium Complex2019Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 25, nr 10, s. 2631-2636Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    1,4- and 1,5-diols undergo cyclodehydration upon treatment with cationic N-heterocyclic carbene (NHC)-Ir-III complexes to give tetrahydrofurans and tetrahydropyrans, respectively. The mechanism was investigated, and a metal-hydride-driven pathway was proposed for all substrates, except for very electron-rich ones. This contrasts with the well-established classical pathways that involve nucleophilic substitution.

  • 345.
    González Miera, Greco
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martínez-Castro, Elisa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Acceptorless Alcohol Dehydrogenation: OH vs NH Effect in Bifunctional NHC–Ir(III) Complexes2018Inngår i: Organometallics, ISSN 0276-7333, E-ISSN 1520-6041, Vol. 37, nr 5, s. 636-644Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bifunctional complexes bearing N-heterocyclic carbene (NHC) ligands functionalized with hydroxy or amine groups were synthesized to measure the beneficial effect of different modes of metal–ligand cooperation in the acceptorless dehydrogenation of alcohols. In comparison to complexes with an amine moiety, hydroxy-functionalized iridium catalysts showed superior activity. In contrast to alcohols, 1,4-diols underwent cyclization to give the corresponding tetrahydrofurans without involving dehydrogenation processes. Mechanistic investigations to rationalize the “OH effect” in these types of complexes have been undertaken.

  • 346. Goulart, Paula N.
    et al.
    da Silva, Clarissa O.
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    The importance of orientation of exocyclic groups in a naphthoxyloside: A specific rotation calculation study2017Inngår i: Journal of Physical Organic Chemistry, ISSN 0894-3230, E-ISSN 1099-1395, Vol. 30, nr 12, artikkel-id e3708Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    2-Naphthyl -d-xylopyranoside (XylNap) inhibits -1,4-galactosyltransferase 7 (4GalT7) and thereby growth of tumor cells both in vitro and in vivo. The binding pocket of 4GalT7 has a defined orientation of hydrogen bond acceptors and hydrophobic moiety. Knowing the orientation of the hydroxyl and naphthyl groups of this molecule would help in the development of more efficient inhibitors. In this work, we have tried, for the first time, to determine the exocyclic hydroxyl and aglycon groups orientation of XylNap, using ab initio descriptions, and calculation of the specific rotation values, in methanol solutions, using 2 different solvent descriptions: a dielectric continuum approach (polarizable continuum model [PCM]) and a microsolvated+continuum approach (MS+PCM). In the PCM approach, [](D)=-59 deg/(dm(g/cm(3))) whereas for the MS+PCM approach [](D)=-29 deg/(dm(g/cm(3))). The latter is in excellent agreement with the experimentally determined value in methanol solution, viz, [](D)=-30 deg/(dm(g/cm(3))). This agreement allows us to say that the hydroxyl groups have similar orientations in xylose and XylNap, and the naphthyl group has a very well-defined dihedral angle value in the most abundant conformations.

  • 347.
    Gudmundsson, Arnar
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Gustafson, Karl P. J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Yang, Bin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient Formation of 2,3-Dihydrofurans via Iron-Catalyzed Cycloisomerization of alpha-Allenols2018Inngår i: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 8, nr 1, s. 12-16Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein, we report a highly efficient iron-catalyzed intramolecular nucleophilic cyclization of alpha-allenols to furnish substituted 2,3-dihydrofurans under mild reaction conditions. A highly diastereoselective variant of the reaction was developed as well, giving diastereomeric ratios of up to 98:2. The combination of the iron-catalyzed cycloisomerization with enzymatic resolution afforded the 2,3-dihydrofuran in high ee. A detailed DFT study provides insight into the reaction mechanism and gives a rationalization for the high chemo-and diastereoselectivity.

  • 348. Gupta, Arvind Kumar
    et al.
    Akkarasamiyo, Sunisa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Orthaber, Andreas
    Rich Coordination Chemistry of pi-Acceptor Dibenzoarsole Ligands2017Inngår i: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 56, nr 8, s. 4504-4511Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of dibenzoarsole (also known as 9-arsafluorene) derivatives have been prepared, and their coordination chemistry has been investigated. The different ligand topology and the arsenic substituents govern the reactivity of the ligands. We report various crystal structures of palladium and platinum complexes derived from this family of ligands. The biphenyl backbone of the bridged bidentate ligands allows very flexible coordination. We have also studied the application of an allylic Pd complex in nucleophilic substitution reactions, revealing that the benzoarsole substituent is susceptible to metal insertion.

  • 349. Gupta, Garima
    et al.
    Gemma, Emiliano
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Oscarson, Stefan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Surolia, Avadhesha
    Defining substrate interactions with calreticulin: an isothermal titration calorimetric study2008Inngår i: Glycoconjugate Journal, ISSN 0282-0080, Vol. 25, nr 8, s. 797-802Artikkel i tidsskrift (Fagfellevurdert)
  • 350.
    Gustafson, Karl P. J.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Gudmundsson, Arnar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Lewis, Kayla
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chemoenzymatic Dynamic Kinetic Resolution of Secondary Alcohols Using an Air- and Moisture-Stable Iron Racemization Catalyst2017Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, nr 5, s. 1048-1051Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein, we report on a metalloenzymatic dynamic kinetic resolution of sec-alcohols employing an iron-based racemization catalyst together with a lipase. The iron catalyst was evaluated in racemization and then used in dynamic kinetic resolution of a number of sec-alcohols to give enantiomerically pure products in good to high yields. The iron catalyst is air and moisture stable and is readily accessible.

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