Sökning: "stereodivergent"

Visar resultat 1 - 5 av 6 avhandlingar innehållade ordet stereodivergent.

  1. 1. Methods for Asymmetric Olefination Reactions; Development and Application to Natural Product Synthesis

    Författare :Daniel Strand; Tobias Rein; Viresh Rawal; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Antitumor agents; Asymmetric Horner-Wadsworth-Emmons; Desymmetrization; Metal-catalyzed olefination; Mucocin; Palladium-catalyzed allylic substitution; Parallel kinetic resolution; Pyranicin; Pyragonicin; Rhenium; Stereoconvergent synthesis; Stereodivergent synthesis; Stereoselective synthesis; Tetrahydropyran; Wittig reaction; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis deals with the development and application of methods for asymmetric olefinations, in particular Horner-Wadsworth-Emmons (HWE) reactions, in the synthesis of certain natural products. Relying on asymmetric HWE reactions to access key building blocks, two natu-ral products, pyranicin and pyragonicin, were synthesized from common late intermediates. LÄS MER

  3. 2. A Regio- and Stereodivergent Route to All Isomers of vic-Amino Alcohols

    Författare :Berit Olofsson; KTH; []
    Nyckelord :amino alcohols; vinylepoxides; vinylaziridines; oxazolines; oxazolidinones; ring-opening; regioselective; diastereoselective; sphingosine; configuration; NMR spectroscopy;

    Sammanfattning : The first part of this thesis describes a synthetic strategythat provides all eight possible isomers of a given vic-aminoalcohol starting from vinylepoxides. The value of a generalroute is evident, as several isomers are needed ininvestigations of structure-activity relationships forpharmacologically active derivatives, and for optimizing theperformance of chiral ligands containing the amino alcoholmoiety. LÄS MER

  4. 3. Synthesis of Novel Polyhydroxyl Surfactants. Influence of the Relative Stereochemistry on Surfactant Properties

    Författare :Kristina Neimert-Andersson; KTH; []
    Nyckelord :Polyhydroxyl surfactants; Sugar surfactants; Stereoselective; Synthesis; Dihydroxylation; Langmuir monolayers; Chiral discrimination;

    Sammanfattning : This thesis deals with the synthesis and characterization ofnovel polyhydroxyl surfactants. The first part describes thesynthesis of a number of stereoisomers of a polyhydroxylsurfactant, and the second part concerns surface chemicalcharacterization. LÄS MER

  5. 4. Synthesis of Organoboronic Acids and Applications in Asymmetric Organocatalysis

    Författare :Sybrand Jonker; Kálmán Szabó; Jörg Pietruszka; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Boronic acid; BINOL; allylboration; propargylation; homologation; stereoselective synthesis; asymmetric synthesis; organocatalysis; allylboronic acid; allenylboronic acid; organisk kemi; Organic Chemistry;

    Sammanfattning : Allyl- and allenylboronic acids are valuable reagents in organic synthesis due to their configurational stability and high reactivity. Few allyl- and allenylboronates are commercially available. Therefore, both the preparation and synthetic application of these organoboronic acids are subjects of study. LÄS MER

  7. 5. Highly enantioselective synthesis of lactam and sugar derivatives by chiral aminocatalysis and merging with transition metal catalysis

    Författare :Zhang Kaiheng; Armando Cordova; Malkov Andrei; Mittuniversitetet; []
    Nyckelord :;

    Sammanfattning : This thesis presented novel methodologies for enantioselectivesynthesis of highly functionalized lactam and sugar derivatives.Asymmetric organocatalysis, cooperative dual catalysis and one-pot multicomponent reaction strategies were applied for the construction of continuous and quaternary stereogenic center. LÄS MER