Endre søk
Begrens søket
1 - 23 of 23
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Treff pr side
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sortering
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
  • Standard (Relevans)
  • Forfatter A-Ø
  • Forfatter Ø-A
  • Tittel A-Ø
  • Tittel Ø-A
  • Type publikasjon A-Ø
  • Type publikasjon Ø-A
  • Eldste først
  • Nyeste først
  • Skapad (Eldste først)
  • Skapad (Nyeste først)
  • Senast uppdaterad (Eldste først)
  • Senast uppdaterad (Nyeste først)
  • Disputationsdatum (tidligste først)
  • Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
  • 1.
    Andersson, Samir
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zou, Dapeng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhang, Rong
    Sun, Shiguo
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Light driven formation of a supramolecular system with three CB 8 s locked between redox-active Ru(bpy)(3) complexes2009Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 7, nr 17, s. 3605-3609Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three CB[8]s have been reversibly locked between two Ru(bpy)(3)-viologen complexes by light driven electron transfer reactions.

  • 2.
    Brulé, Emilie
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Hii, K K
    de Miguel, Y R
    Polymer-supported manganese porphyrin catalysts - peptide-linker promoted chemoselectivity2005Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 3, nr 10, s. 1971-1976Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Manganese porphyrin catalysts were tethered to polymer-supports via peptide linkers. The reactivity and chemoselectivity of the catalysts were assessed in the epoxidation of limonene. It was found that the inclusion of a peptide linker incorporating a donor heteroatom which could act as an axial ligand led to a supported manganese porphyrin catalyst with unprecedented selectivity and stability.

  • 3.
    Cassimjee, Karim Engelmark
    et al.
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Humble, Maria Svedendahl
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Land, Henrik
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Abedi, Vahak
    Berglund, Per
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Chromobacterium violaceum omega-transaminase variant Trp60Cys shows increased specificity for (S)-1-phenylethylamine and 4 '-substituted acetophenones, and follows Swain-Lupton parameterisation2012Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 10, nr 28, s. 5466-5470Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    For biocatalytic production of pharmaceutically important chiral amines the.-transaminase enzymes have proven useful. Engineering of these enzymes has to some extent been accomplished by rational design, but mostly by directed evolution. By use of a homology model a key point mutation in Chromobacterium violaceum omega-transaminase was found upon comparison with engineered variants from homologous enzymes. The variant Trp60Cys gave increased specificity for (S)-1-phenylethylamine (29-fold) and 4'-substituted acetophenones (similar to 5-fold). To further study the effect of the mutation the reaction rates were Swain-Lupton parameterised. On comparison with the wild type, reactions of the variant showed increased resonance dependence; this observation together with changed pH optimum and cofactor dependence suggests an altered reaction mechanism.

  • 4.
    Deng, Lingquan
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Norberg, Oscar
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Uppalapati, Suji
    Yan, Mingdi
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ramström, Olof
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Stereoselective synthesis of light-activatable perfluorophenylazide-conjugated carbohydrates for glycoarray fabrication and evaluation of structural effects on protein binding by SPR imaging2011Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 9, nr 9, s. 3188-3198Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of light-activatable perfluorophenylazide (PFPA)-conjugated carbohydrate structures have been synthesized and applied to glycoarray fabrication. The glycoconjugates were structurally varied with respect to anomeric attachment, S-, and O-linked carbohydrates, respectively, as well as linker structure and length. Efficient stereoselective synthetic routes were developed, leading to the formation of the PFPA-conjugated structures in good yields over few steps. The use of glycosyl thiols as donors proved especially efficient and provided the final compounds in up to 70% total yield with high anomeric purities. PFPA-based photochemistry was subsequently used to generate carbohydrate arrays on a polymeric surface, and surface plasmon resonance imaging (SPRi) was applied for evaluation of carbohydrate-protein interactions using the plant lectin Concanavalin A (Con A) as a probe. The results indicate better performance and equal efficiency of S-and O-linked structures with intermediate linker length.

  • 5. Ding, Yubin
    et al.
    Li, Tong
    Li, Xin
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Zhu, Weihong
    Xie, Yongshu
    From nonconjugation to conjugation: novel meso-OH substituted dipyrromethanes as fluorescence turn-on Zn2+ probes2013Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 11, nr 16, s. 2685-2692Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Most reported Zn2+ probes suffer from the interference of background fluorescence originated from the conjugated structures of commonly utilized fluorophores. In this work, three novel meso-hydroxyl group substituted dipyrromethanes DPMOH1-DPMOH3 were synthesized and found to be colourless and nonfluorescent due to the interruption of the conjugated p system by an sp(3) carbon between the two pyrrolic units. Interestingly, only the addition of Zn2+ to the solutions of DPMOH1-DPMOH3 promoted their oxidation to dipyrrin forms, and bright fluorescence "turn on" was observed due to the formation of corresponding dipyrrin complexes with the dipyrrin : zinc stoichiometry of 2 :1. Zn2+ detection mechanism was investigated by UV-Vis, fluorescence, H-1 NMR and HRMS analyses, which can be ascribed to the CHEF type fluorescence enhancement, resulting from good rigidity of the dipyrrin complexes. Hence, DPMOH1-DPMOH3 can be used as fluorescence turn-on Zn2+ probes with the advantage of no background fluorescence.

  • 6.
    Dinér, Peter
    et al.
    Department of Chemistry, University of Gothenburg.
    Amedjkouh, Mohamed
    Aminophosphonates as organocatalysts in the direct asymmetric aldol reaction towards syn selectivity in the presence of Lewis bases2006Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 4, nr 11, s. 2091-2096Artikkel i tidsskrift (Fagfellevurdert)
  • 7.
    Dong, Hai
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Rahm, Martin
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Thota, Niranjan
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Deng, Lingquan
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Brinck, Tore
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi.
    Ramström, Olof
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Control of the ambident reactivity of the nitrite ion2013Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 11, nr 4, s. 648-653Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In previous studies, it was reported that a neighbouring equatorial ester group is essential for a good yield of nitrite-mediated triflate inversion, whereas with neighbouring benzyl ether groups or axial ester groups, mixtures are generally produced. In the present study, the origin of this difference was addressed. The ambident reactivity of the nitrite ion has been found to be the cause of the complex product formation observed, which can be controlled by a neighbouring equatorial ester group. Both N-attack and O-attack occur in the absence of the ester group, whereas O-attack is favoured in its presence. A neighbouring group assistance mechanism is proposed, in addition to steric effects, based on secondary interactions between the neighbouring ester group and the incoming nucleophile. High-level quantum mechanical calculations were carried out in order to delineate this effect. The theoretical results are in excellent agreement with experiments, and suggest a catalytic role for the neighbouring equatorial ester group.

  • 8. Eneyskaya, E. V.
    et al.
    Ivanen, D. R.
    Shabalin, K. A.
    Kulminskaya, A. A.
    Backinowsky, L. V.
    Brumer, Harry
    KTH, Skolan för bioteknologi (BIO), Glykovetenskap.
    Neustroev, K. N.
    Chemo-enzymatic synthesis of 4-methylumbelliferyl beta-(1 -> 4)-D-xylooligosides: new substrates for beta-D-xylanase assays2005Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 3, nr 1, s. 146-151Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Transglycosylation catalyzed by a beta-D-xylosidase from Aspergillus sp. was used to synthesize a set of 4-methylumbelliferyl (MU) beta-1-->4-D-xylooligosides having the common structure [beta-D-Xyl-(1-->4)](2-5)-beta- D-Xyl-MU. MU xylobioside synthesized chemically by the condensation of protected MU beta-D-xylopyranoside with ethyl 2,3,4-tri-O-acetyl-1-thio-beta-D-xylopyranoside was used as a substrate for transglycosylation with the beta-D- xylosidase from Aspergillus sp. to produce higher MU xylooligosides. The structures of oligosaccharides obtained were established by H-1 and C-13 NMR spectroscopy and electrospray tandem mass spectrometry. MU beta-D-xylooligosides synthesized were tested as fluorogenic substrates for the GH-10 family beta-D-xylanase from Aspergillus orizae and the GH-11 family beta-D- xylanase I from Trichoderma reesei. Both xylanases released the aglycone from MU xylobioside and the corresponding trioside. With substrates having d.p. 4 and 5, the enzymes manifested endolytic activities, splitting off MU, MUX, and MUX2 primarily.

  • 9.
    Engström, Karin
    et al.
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem.
    Vallin, Michaela
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Syrén, Per-Olof
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Hult, Karl
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Bäckvall, Jan-E.
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem.
    Mutated variant of Candida antarctica lipase B in (S)-selective dynamic kinetic resolution of secondary alcohols2011Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 9, nr 1, s. 81-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An (S)-selective dynamic kinetic resolution of secondary alcohols, employing a mutated variant of Candida antarctica lipase B (CalB) gave products in 84-88% yield and in 90-97% ee.

  • 10. Friberg, Annika
    et al.
    Johanson, Ted
    Franzén, Johan
    Division of Organic Chemistry, Center for Chemistry and Chemical Engineering, Lund University.
    Gorwa-Grauslund, Marie F.
    Frejd, Torbjoern
    Efficient bioreduction of bicyclo[2.2.2]octane-2,5-dione and bicyclo[2.2.2]oct-7-ene-2,5-dione by genetically engineered Saccharomyces cerevisiae2006Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 4, nr 11, s. 2304-2312Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A screening of non-conventional yeast species and several Saccharomyces cerevisiae ( baker's yeast) strains overexpressing known carbonyl reductases revealed the S. cerevisiae reductase encoded by YMR226c as highly efficient for the reduction of the diketones 1 and 2 to their corresponding hydroxyketones 3 - 6 ( Scheme 1) in excellent enantiomeric excesses. Bioreduction of 1 using the genetically engineered yeast TMB4100, overexpressing YMR226c, resulted in > 99% ee for hydroxyketone (+)- 4 and 84 - 98% ee for (-)- 3, depending on the degree of conversion. Baker's yeast reduction of diketone 2 resulted in > 98% ee for the hydroxyketones (+)- 5 and (+)- 6. However, TMB4100 led to significantly higher conversion rates ( over 40 fold faster) and also a minor improvement of the enantiomeric excesses (> 99%).

  • 11.
    Holmgren, Anders
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Brunow, Gösta
    Department of Chemistry, University of Helsinki.
    Henriksson, Gunnar
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Zhang, Liming
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Träkemi och massateknologi.
    Ralph, John
    US Dairy Forage Research Center, USDA-Agricultural Research Service.
    Non-enzymatic reduction of quinone methides during oxidative coupling of monolignols: implications for the origin of benzyl structures in lignins2006Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 4, nr 18, s. 3456-3461Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lignin is believed to be synthesized by oxidative coupling of 4-hydroxyphenylpropanoids. In native lignin there are some types of reduced structures that cannot be explained solely by oxidative coupling. In the present work we showed via biomimetic model experiments that nicotinamide adenine dinucleotide ( NADH), in an uncatalyzed process, reduced a beta-aryl ether quinone methide to its benzyl derivative. A number of other biologically significant reductants, including the enzyme cellobiose dehydrogenase, failed to produce the reduced structures. Synthetic dehydrogenation polymers of coniferyl alcohol synthesized ( under oxidative conditions) in the presence of the reductant NADH produced the same kind of reduced structures as in the model experiment, demonstrating that oxidative and reductive processes can occur in the same environment, and that reduction of the in situ-generated quinone methides was sufficiently competitive with water addition. In situ reduction of beta - beta-quinone methides was not achieved in this study. The origin of racemic benzyl structures in lignins therefore remains unknown, but the potential for simple chemical reduction is demonstrated here.

  • 12.
    Hu, Lei
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Zhang, Yan
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ramström, Olof
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Lipase-catalyzed asymmetric synthesis of oxathiazinanones through dynamic covalent kinetic resolution2014Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 12, nr 22, s. 3572-3575Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A domino addition-lactonization pathway has been applied to a dynamic covalent resolution protocol, leading to efficient oxathiazinanone formation as well as chiral discrimination. A new, double biocatalytic pathway has furthermore been proposed and evaluated where the initial product inhibition could be efficiently circumvented.

  • 13. Klein, Michael
    et al.
    Dinér, Peter
    University of Gothenburg.
    Dorin-Semblat, Dominique
    Doerig, Christian
    Grøtli, Morten
    Synthesis of 3-(1,2,3-triazol-1-yl)- and 3-(1,2,3-triazol-4-yl)-substituted pyrazolo[3,4-d]pyrimidin-4-amines via click chemistry: potential inhibitors of the Plasmodium falciparum PfPK7 protein kinase2009Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 7, nr 17, s. 3421-3429Artikkel i tidsskrift (Fagfellevurdert)
  • 14. Kona, Juraj
    et al.
    Brinck, Tore
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi.
    A combined molecular dynamics simulation and quantum chemical study on the mechanism for activation of the OxyR transcription factor by hydrogen peroxide2006Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 4, nr 18, s. 3468-3478Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Molecular dynamics (MD) simulations have been performed on the regulatory domain of the Escherichia coli OxyR transcription factor for the different chemical states along the mechanistic cycle for its activation by hydrogen peroxide. Conformational analysis indicates that His198 and Arg220 catalytic residues can be involved in the biochemical process of activation of OxyR. On the basis of the simulation data, a detailed mechanism for the oxidation process is suggested in which His198, in the presence of an arginine residue, functions as a unique acid - base catalyst in the successive oxidations of Cys199 and Cys208 by hydrogen peroxide. This mechanistic proposal has been tested by density functional theory (DFT-B3LYP) and ab initio (MP2) calculations on model systems. The two oxidations are both identified as nucleophilic substitution reactions of S(N)2 type with deprotonated cysteines functioning as nucleophiles. Both reactions have a calculated free energy of activation close to 15 kcal mol(-1), which is consistent with the available experimental data on the kinetics of the activation process.

  • 15.
    Kärkäs, Markus D.
    et al.
    Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
    Matsuura, Bryan S.
    Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
    Monos, Timothy M.
    Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
    Magallanes, Gabriel
    Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
    Stephenson, Corey R. J.
    Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
    Transition-Metal Catalyzed Valorization of Lignin: The Key to a Sustainable Carbon-Neutral Future2016Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 14, nr 6, s. 1853-1914Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The development of a sustainable, carbon-neutral biorefinery has emerged as a prominent scientific and engineering goal of the 21st century. As petroleum has become less accessible, biomass-based carbon sources have been investigated for utility in fuel production and commodity chemical manufacturing. One underutilized biomaterial is lignin; however, its highly crosslinked and randomly polymerized composition have rendered this biopolymer recalcitrant to existing chemical processing. More recently, insight into lignin's molecular structure has reinvigorated chemists to develop catalytic methods for lignin depolymerization. This review examines the development of transition-metal catalyzed reactions and the insights shared between the homogeneous and heterogeneous catalytic systems towards the ultimate goal of valorizing lignin to produce value-added products.

  • 16.
    Linder, Mats
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi.
    Brinck, Tore
    KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi.
    Synergistic activation of the Diels-Alder reaction by an organic catalyst and substituents: a computational study2009Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 7, nr 7, s. 1304-1311Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Density functional theory (DFT), using the hybrid functionals B3LYP and B2PLYP, has been employed to investigate the activation of the acrolein-butadiene Diels-Alder reaction, mediated by a thiourea catalyst. Effects due to electron-donating groups (EDGs) on the diene, as well as electron-withdrawing groups (EWGs) on the dienophile, have also been studied. Organic catalysts such as thioureas are known to lower the activation energy through hydrogen-bonding to the carbonyl oxygen, in a way that mimics the oxyanion holes of hydrolytic enzymes. EDGs and EWGs were found to further activate the reaction, and the catalyst showed a synergistic behavior towards the EDGs. Polar solvents were found to reduce the overall activation energy, but also the relative catalytic effect of the thiourea, in accordance with experimental studies. The substituent-mediated reactions displayed more asynchronous transition structures with lower activation energy, which led us to investigate the possibility of an alternative two-step, Michael-type route, similar to what has been found in macrophomate synthase. Although the concerted Diels-Alder route was found to be favored over the Michael route, the calculated activation energy difference is less than 1 kcal mol(-1), which suggests that the two mechanisms compete, and could be responsible for the particular stereochemical outcome of an experiment.

  • 17. Martín-Santamaría, Sonsoles
    et al.
    André, Sabine
    Buzamet, Eliza
    Caraballo, Rémi
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Fernández-Cureses, Gloria
    Morando, Maria
    Ribeiro, Joao P.
    Ramírez-Gualito, Karla
    de Pascual-Teresa, Beatriz
    Javier Cañada, F.
    Menéndez, Margarita
    Ramström, Olof
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Jiménez-Barbero, Jesus
    Solís, Dolores
    Gabius, Hans-Joachim
    Symmetric dithiodigalactoside: strategic combination of binding studies and detection of selectivity between a plant toxin and human lectins2011Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 9, nr 15, s. 5445-5455Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thioglycosides offer the advantage over O-glycosides to be resistant to hydrolysis. Based on initial evidence of this recognition ability for glycosyldisulfides by screening dynamic combinatorial libraries, we have now systematically studied dithiodigalactoside on a plant toxin (Viscum album agglutinin) and five human lectins (adhesion/growth-regulatory galectins with medical relevance e.g. in tumor progression and spread). Inhibition assays with surface-presented neoglycoprotein and in solution monitored by saturation transfer difference NMR spectroscopy, flanked by epitope mapping, as well as isothermal titration calorimetry revealed binding properties to VAA (K(a): 1560 +/- 20 M (1)). They were reflected by the structural model and the affinity on the level of toxin-exposed cells. In comparison, galectins were considerably less reactive, with intrafamily grading down to very minor reactivity for tandem-repeat-type galectins, as quantitated by radioassays for both domains of galectin-4. Model building indicated contact formation to be restricted to only one galactose moiety, in contrast to thiodigalactoside. The tested glycosyldisulfide exhibits selectivity between the plant toxin and the tested human lectins, and also between these proteins. Therefore, glycosyldisulfides have potential as chemical platform for inhibitor design.

  • 18. Pei, Y. X.
    et al.
    Brule, E.
    Moberg, Christina
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Modular multidentate phosphine ligands: application to palladium-catalyzed allylic alkylations2006Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 4, nr 3, s. 544-550Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multidentate phosphines were readily obtained by reaction of chiral multidentate amines, prepared via ring opening of (S)-N-tosyl-2-isopropylaziridine with ammonia, primary, and secondary amines, with achiral phosphorus containing building blocks. The phosphines were used in palladium-catalyzed alkylation of rac-3-cyclohexenyl and cyclopentenyl carbonates. The enantioselectivity and reactivity were largely dependent on the structure of the amine core of the ligands. Up to 88% ee was observed in reactions with the six-membered substrate.

  • 19. Poon, Jia-Fei
    et al.
    Alao, John Patrick
    Sunnerhagen, Per
    Dinér, Peter
    Uppsala University.
    Azastilbenes: a cut-off to p38 MAPK inhibitors2013Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 11, nr 27Artikkel i tidsskrift (Fagfellevurdert)
  • 20. Rubio-Magnieto, J.
    et al.
    Di Meo, F.
    Lo, M.
    Delcourt, C.
    Clément, S.
    Norman, Patrick
    Linköping University, Sweden.
    Richeter, S.
    Linares, M.
    Surin, M.
    Binding modes of a core-extended metalloporphyrin to human telomeric DNA G-quadruplexes2015Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 13, nr 8, s. 2453-2463Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The molecular recognition of human telomeric G-quadruplexes by a novel cationic π-extended NiII-porphyrin (NiII-TImidP4) is studied in aqueous solutions via (chir)optical spectroscopy, Fluorescence Resonance Energy Transfer (FRET) melting assay, and computational molecular modeling. The results are systematically compared with the recognition by a conventional meso-substituted NiII-porphyrin (NiII-TMPyP4), which allows us to pinpoint the differences in binding modes depending on the G-quadruplex topology. Importantly, FRET melting assays show the higher selectivity of NiII-TImidP4 towards human telomeric G4 than that of NiII-TMPyP4.

  • 21.
    Sakulsombat, Morakot
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Vongvilai, Pornrapee
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    Ramström, Olof
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi.
    In Situ Evaluation of Lipase Performances Through Dynamic Asymmetric Cyanohydrin Resolution2011Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 9, nr 4, s. 1112-1117Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A dynamic resolution process based on multiple reversible cyanohydrin formation coupled to lipase-mediated transesterification is demonstrated. The resulting process resulted in the efficient evaluation of complex lipase performances in asymmetric cyanohydrin acylate synthesis. Dynamic systems were generated and resolved in situ, and the effects of the reaction conditions could be directly monitored for the overall system. By this concept, the enzyme activity, chemo- and stereoselectivity for all involved substrates could be simultaneously evaluated.

  • 22.
    Torssell, Staffan
    et al.
    KTH, Tidigare Institutioner                               , Kemi.
    Somfai, Peter
    KTH, Tidigare Institutioner                               , Kemi.
    A Practical Synthesis of D-erythro-Sphingosine Using a Cross-Metathesis Approach2004Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 2, nr 11, s. 1643-1646Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Starting from a vinylepoxide, a short and practical synthesis of D-erythro-sphingosine is described. The key transformations are a regioselective opening of the vinylepoxide and an E-selective cross-metathesis, affording the target molecule in 5 steps and 51% overall yield.

  • 23.
    Zhang, Liming
    et al.
    KTH, Tidigare Institutioner                               , Fiber- och polymerteknologi.
    Henriksson, Gunnar
    KTH, Tidigare Institutioner                               , Pappers- och massateknik.
    Gellerstedt, Göran
    KTH, Tidigare Institutioner                               , Pappers- och massateknik.
    The formation of beta-beta structures in lignin biosynthesis - are there two different pathways?2003Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 1, nr 20, s. 3621-3624Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Based on results from 2D NMR studies, both pinoresinol and secoisolariciresinol structures were found to be present in native lignin from spruce wood as well as in spruce kraft lignin and residual kraft pulp lignin. These two structures constitute the major types of beta-beta inter-unit linkages present in spruce lignin, but their formation in the lignin polymer may follow different pathways leading to their different bonding patterns with the rest of the lignin polymer. The mechanisms involved are discussed.

1 - 23 of 23
RefereraExporteraLink til resultatlisten
Permanent link
Referera
Referensformat
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf