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  • 1.
    Andersson, Pher
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Sharpless, K. Barry
    A Dramatic Ligand Effect on the Relative Reactive Reactivites of Substituted Alkenes with Osmium Tetroxide1993In: J. Am. Chem. Soc., no 115, p. 7047-7048Article in journal (Refereed)
  • 2.
    Berglund, P.
    et al.
    Mid Sweden University.
    Holmquist, M.
    Hedenstrom, E.
    Hult, K.
    Hogberg, H. -E
    2-Methylalkanoic acids resolved by esterification catalysed by lipase from Candida rugosa: Alcohol chain length and enantioselectivity1993In: Tetrahedron Asymmetry, ISSN 09574166 (ISSN), Vol. 4, no 8, p. 1869-1878Article in journal (Refereed)
    Abstract [en]

    Enantiomerically pure (R)-2-methyldecanoic acid and (S)-2-methyl-1-decanol were prepared in a multi gram scale by esterification reactions catalysed by lipase from Candida rugosa. The enantiomeric ratios (E-values) were determined as a function of the chain length of the alcohol used as the complementary substrate in cyclohexane. In the resolution of 2-methyldecanoic acid the highest value (E = 37 ± 5) was obtained, when either 2-hexanol, 1-heptanol or 1-octanol were used. In contrast, when resolving 2-methyloctanoic acid, the E-values increased continually with increasing chain length of the alcohol used. 1-Hexadecanol gave the highest value: E > 100. The E-values were determined from the enantiomeric excess (ee) of the product at a conversion below 0.4. After two consecutive esterification reactions enantiomerically pure (R)-2-methyldecanoic acid, >99.8% ee, and after subsequent reduction of the ester produced, (S)-2-methyl-1-decanol, 96.7% ee, were obtained.

  • 3.
    Bäckvall, Jan-E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Granberg, Kennth L.
    Andersson, Pher
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Gatti, Roberto
    Gogoll, Adolf
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Stereocontrolled Lactonization Reactions via Palladium-Catalyzed 1,4-Addittion to Conjugated Dienes1993In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 58, no 20, p. 5445-5451Article in journal (Refereed)
    Abstract [en]

    Stereocontrolledp alladium(I1)-catalyzed1 ,4-chloro-and 1,4-acetoxylactonizations o f conjugated cyclic dienes have been developed to give stereodefined fused lactones. The stereochemistry of the 1,4- acetoxylactonization was controlled by the ligand on the metal catalyst, and in this way either a cisor truns-acetoxylactonization was obtained. This dual stereoselectivity is explained by a stereocontrolled acetate attack (trans or cis, respectively) on the allyl group in the catalytic (π-allyl)- palladium intermediate. To further strengthen the mechanism the intermediate (π-ally1)palladium complex was isolated and fully characterized. A stereospecific synthesis of cis-  and truns-2-[6- (benzyloxy)-2,4-heptadien-l-yllacetic a cid (cis-  and truns-9) followed by stereoselective Pd(I1)- catalyzed chloro- and acetoxylactonization in acetonelacetic acid resulted in highly functionalized fused lactones with control of the relative stereochemistry at four different carbons.

  • 4. Holmquist, M.
    et al.
    Martinelle, M.
    Berglund, P.
    Mid Sweden University.
    Clausen, I. G.
    Patkar, S.
    Svendsen, A.
    Hult, K.
    Lipases from Rhizomucor miehei and Humicola lanuginosa: Modification of the lid covering the active site alters enantioselectivity1993In: Journal of Protein Chemistry, ISSN 02778033 (ISSN), Vol. 12, no 6, p. 749-757Article in journal (Refereed)
    Abstract [en]

    The homologous lipases from Rhizomucor miehei and Humicola lanuginosa showed approximately the same enantioselectivity when 2-methyldecanoic acid esters were used as substrates. Both lipases preferentially hydrolyzed the S- enantiomer of 1-heptyl 2-methyldecanoate (R. miehei: E(S) = 8.5; H. lanuginosa: E(S) = 10.5), but the R-enantiomer of phenyl 2-methyldecanoate (E(R) = 2.9). Chemical arginine specific modification of the R. miehei lipase with 1,2-cyclohexanedione resulted in a decreased enantioselectivity (E(R) = 2.0), only when the phenyl ester was used as a substrate. In contrast, treatment with phenylglyoxal showed a decreased enantioselectivity (E(S) = 2.5) only when the heptyl ester was used as a substrate. The presence of guanidine, an arginine side chain analog, decreased the enantioselectivity with the heptyl ester (E(S) = 1.9) and increased the enantioselectivity with the aromatic ester (E(R) = 4.4) as substrates. The mutation, Glu 87 Ala, in the lid of the H. lanuginosa lipase, which might decrease the electrostatic stabilization of the open-lid conformation of the lipase, resulted in 47% activity compared to the native lipase, in a tributyrin assay. The Glu 87 Ala mutant showed an increased enantioselectivity with the heptyl ester (E(S) = 17.4) and a decreased enantioselectivity with the phenyl ester (E(R) = 2.5) as substrates, compared to native lipase. The enantioselectivities of both lipases in the esterification of 2-methyldecanoic acid with 1-heptanol were unaffected by the lid modifications.

  • 5. Högberg, Hans-Erik
    et al.
    Edlund, Helen
    Berglund, Per
    KTH, School of Biotechnology (BIO), Biochemistry (closed 20130101).
    Hedenström, Erik
    WATER ACTIVITY INFLUENCES ENANTIOSELECTIVITY IN A LIPASE-CATALYZED RESOLUTION BY ESTERIFICATION IN AN ORGANIC-SOLVENT1993In: Tetrahedron: asymmetry, ISSN 0957-4166, E-ISSN 1362-511X, Vol. 4, no 10, p. 2123-2126Article in journal (Refereed)
    Abstract [en]

    The enantioselectivity of Candida rugosa lipase-mediated esterification of 2-methylalkanoic acids with n-alcohols in cyclohexane is dependent on water activity.

  • 6. Kolb, Hartmuth
    et al.
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Bennani, Youssef
    Crispino, Gerard
    Jeong, Kyu-Sung
    Kwong, Hoi-Lun
    Sharpless, K. Barry
    On1993In: J. Am. Chem. Soc., no 115, p. 12226-12227Article in journal (Refereed)
  • 7. Morikawa, Kouhei
    et al.
    Park, Jeonghan
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Hashiyama, Tomiki
    Sharpless, K. Barry
    Catalytic Asymmetric Dihydroxylation of Tetrasubstituted Oelfins1993In: J. Am. Chem. Soc., no 115, p. 8463-8464Article in journal (Refereed)
  • 8. Murakami, Masahiro
    et al.
    Suginome, Michinori
    Fujimoto, Kenzo
    Nakamura, Hiroshi
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Ito, Yoshihiko
    Stereoselective Intramolecular Bis-Silylation of Alkenes Promoted by a Palladium-Isocyanide Catalyst Leading to Polyol Synthesis1993In: Stereoselective Intramolecular Bis-Silylation of Alkenes Promoted by a Palladium-Isocyanide Catalsyst Leading to Polyol Synthesis, no 115, p. 6487-6498Article in journal (Refereed)
  • 9. Nilsson, Ylva I. M.
    et al.
    Andersson, Pher
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Bäckvall, Jan-E.
    Example of Theromodynamic Control in Palladium-Catalyzed Allylic Alkylation. Evidence for Palladium-Assisted Allylic C-C Bond Cleavage1993In: J. Am. Chem. Soc., no 115, p. 6609-6613Article in journal (Refereed)
  • 10.
    Sandberg Hiltunen, Maria
    Umeå University, Faculty of Social Sciences, Centre for Demographic and Ageing Research (CEDAR).
    DNA and peptide sequences and chemical processes multivariately modelled by principal component analysis and partial least-squares projections to latent structures1993In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 277, p. 239-253Article in journal (Refereed)
    Abstract [en]

    Biopolymer sequences (e.g., DNA, RNA, proteins and polysaccharides) and chemical processes (e.g., a batch or continuous polymer synthesis run in a chemical plant) have close similarities from the modelling point of view. When a set of sequences or processes is characterized by multivariate data, a three-way data matrix is obtained. With sequences the position and with processes the time is one direction in this matrix. The multivariate modelling of this matrix by principal component analysis (PCA) or partial least-squares (PLS) methods for the following purposes is discussed: classification of sequences; quantitative relationships between sequence and biological activity or chemical properties; optimizing a sequence with respect to selected properties; process diagnostics; and quantitative relationships between process variables and product quality variables. To obtain good models, a number of problems have to be adequately dealt with: appropriate characterization of the sequence or process; experimental design (selecting sequences or process settings); transforming the three-way into a two-way matrix; and appropriate modelling and validation (modelling interactions, periodicities, “time series” structures and “neighbour effects”). A multivariate approach to sequence and process modelling using PCA and PLS projections to latent structures is discussed and illustrated with several sets of peptide and DNA promoter data.

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