Sökning: "Asymmetric synthesis"

Visar resultat 1 - 5 av 140 avhandlingar innehållade orden Asymmetric synthesis.

  1. 1. Absolute Asymmetric Synthesis

    Detta är en avhandling från Göteborg : Chalmers University of Technology

    Författare :Anders Lennartson; Göteborgs universitet.; Gothenburg University.; [2009]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; absolute asymmetric synthesis; enantioselective synthesis; chirality; optical resolution; spontaneous resolution; conglomerate; organozinc reagents; organometallic chemistry; coordination chemistry; supramolecular chemistry; intermolecular interactions;

    Sammanfattning : Absolute asymmetric synthesis is the synthesis of optically active products from achiral or racemic precursors only. This has generally been regarded as impossible and is relevant in the discussion of the origins of biomolecular homochirality. LÄS MER

  2. 2. Asymmetric Hydrogenations Syntheses of Ligands and Expansion of Substrate Scope

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Pradeep Cheruku; Uppsala universitet.; [2008]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Catalysis; Asymmetric; Hydrogenations; Reductions; Olefins; Imines; Enol phosphinates; Transition metal; Complexes; Iridium; Enamines; Ruthenium; Ligands; Trifluoromethyl; Diphenylvinylphosphine oxides; Vinyl phosphonates; NATURAL SCIENCES Chemistry; NATURVETENSKAP Kemi;

    Sammanfattning : Asymmetric hydrogenation has emerged as a versatile methodology to obtain a wide range of chiral precursors. This thesis focused on the synthesis of new chiral ligands and the expansion of the substrate scope of asymmetric hydrogenations. LÄS MER

  3. 3. Stereoselective Synthesis of Amino Alcohols Applications to Natural Product Synthesis

    Detta är en avhandling från Stockholm : KTH

    Författare :Staffan Torssell; KTH.; [2007]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Amino alcohol; asymmetric 1.3-dipolar cycloaddition; azomethine ylide; carbenoid; carbonyl ylide; cross-metathesis; omuralide; oxazolidine; rhodium; sphingosine; stemoamide; stereoselective synthesis; total synthesis.; NATURAL SCIENCES Chemistry Organic chemistry; NATURVETENSKAP Kemi Organisk kemi;

    Sammanfattning : This thesis is divided into four separate parts with amino alcohols as the common feature.The first part of the thesis describes the development of an efficient three-component approach to the synthesis of α-hydroxy-β-amino esters. LÄS MER

  4. 4. Asymmetric Synthesis of C-Glycosylated Amino Acids Incorporation in Collagen Glycopeptides and Evaluation in a Model for Rheumatoid Arthritis

    Detta är en avhandling från Umeå : Kemi

    Författare :Tomas Gustafsson; Umeå universitet.; [2005]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Total synthesis; stereoselective synthesis; chiral glycine templates; Evan’s alkylation; asymmetric hydrogenation; alpha-amino acid synthesis; C-glycoside; rheumatoid arthritis; MHC; T cell; NATURAL SCIENCES Chemistry Organic chemistry; NATURVETENSKAP Kemi Organisk kemi;

    Sammanfattning : This thesis describes stereoselective syntheses of four amino acids, three of which are C-glycosidic analogues of glycosylated amino acids. The overall goal of the project was to probe the interactions between MHC molecules, glycopeptide antigens and T cell receptors, that are essential for development of collagen induced arthritis. LÄS MER

  5. 5. Chemoenzymatic Resolution in Dynamic Systems Screening, Classification and Asymmetric Synthesis

    Detta är en avhandling från Stockholm : KTH Royal Institute of Technology

    Författare :Yan Zhang; KTH.; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; constitutional dynamic chemistry; dynamic systemic resolution; dynamic kinetic resolution; enzyme catalysis; transesterification; enzyme promiscuity; asymmetric synthesis; pattern recognition; self-inhibition.;

    Sammanfattning : This  thesis  is  divided  into  four  parts,  all  centered  around  Constitutional Dynamic  Chemistry  (CDC)  and  Dynamic  Kinetic  Resolution  (DKR)  using biocatalysts for selective transformations, and their applications in screening of bioactive compounds, organic synthesis, and enzyme classification.   In  part  one,  an  introduction  to  CDC  and  DKR  is  presented,  illustrating  the basic  concepts,  practical  considerations  and  potential  applications  of  such dynamic systems, thus providing the background information for the studies in the following chapters. LÄS MER