Sökning: "Acetals"

Visar resultat 16 - 20 av 22 avhandlingar innehållade ordet Acetals.

  1. 16. Photoredox catalysis harnessing oxygen-centered radicals

    Författare :Alica Ondrejkova; Göteborgs universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen-centered radical; photoredox catalysis; C-H functionalization; visible light;

    Sammanfattning : Visible light provides an abundant and renewable source of energy with an ample capacity to mediate chemical transformations. Photoredox catalysis utilizes this energy for the generation of high-energy radical intermediates and strategically employs these reactive species in versatile chemical transformations. LÄS MER

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

    Författare :Tomas Gustafsson; Jan Kihlberg; Umeå universitet; []
    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; Organic chemistry; 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

  3. 18. Design and synthesis of glycose-derivatives and related molecules for cell membrane mimetics

    Författare :Jing Shi; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : A series of glucopyranose (α-D-glucose, β-D-glucose, D-gluconic acid and 6-amino-6-deoxy-D-glocuse) terminated alkanethiol acetals have been successfully synthesized. α and β-D-glucose were configured in controlled ways coupling with alkanethiol, in which bromosugar and trichloroacetirnidates were selected as activated glycosyl donors using different promoters tetraalkylammonium bromide (Et4NBr) and trimethylsilanetriflate (TMSOTf) respectively. LÄS MER

  4. 19. New Applications of Monoorganocopper/Iodotrimethylsilane Reagents in Conjugate Additions

    Författare :Magnus Eriksson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; beta-unsaturated; halosilane; conjugate addition; alpha; copper iodide; copper acetylides; organocopper; iodotrimethylsilane; Claisen rearrangement;

    Sammanfattning : The thesis reports new applications of monoorganocopper compounds, RCu(LiI), and iodotrimethylsilane in conjugate additions. The present investigation demonstrates conjugate addition of alkylcopper compounds and iodotrimethylsilane to reactive .alpha.,. LÄS MER

  5. 20. Application of metalation reactions for synthesis of sulfur/selenium-containing heterocyclic compounds

    Författare :Hamid Shirani; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Heterocycles; indoles; 3- arylthio indoles; thiopyranobisindoles; dibenzothiepins; 3; 3′-dithiobisindoles; alkaloids; echinosulfone A; cyclization; ortho-metalation; McMurry coupling; sulfides; sulfones and disulfides;

    Sammanfattning : This thesis deals mainly with the synthesis of various sulfur/selenium-containing heterocyclic compounds, many of which include structural features present in several biologically active molecules, with particular emphasis on compounds of synthetic importance, such as indoles, as well as other heteroaromatic species. In the first part, an efficient procedure toward synthesis of new 3-(arylthio)indoles based on reactions of aryl Grignard reagents or lithiated heteroaromatics with protected 3,3′-dithiobisindoles is described. LÄS MER