Sökning: "stereochemistry"

Visar resultat 1 - 5 av 44 avhandlingar innehållade ordet stereochemistry.

  1. 1. Lignin Model Compounds: Synthesis, Stereochemistry and Acidolysis

    Författare :Shiming Li; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; boric acid complexes; Arylglycerol b-aryl ethers; stereochemistry; 3-Diaryl-2-propen-1-ols; 1; Phenylcoumarans; lignin model compounds; acidolysis; ion-exchange chromatography; 3-propanediols; 2-Diaryl-1; 2; X-ray crystallography;

    Sammanfattning : Lignin model compounds representative of structural elements in lignin of the b-1, b-5, b-O-4, cinnamaldehyde and cinnamyl alcohol types were synthesized. erythro-Forms of b-1 models of the 1,2-diaryl-1,3-propanediol type were prepared by BF3-catalyzed rearrangement of chalcone epoxides and subsequent reduction of the rearrangement products with NaBH4. LÄS MER

  3. 2. Investigations of New Biomimetic Transamination Systems and Inclusion Complexation with Cyclodextrins

    Författare :Anders Hjelmencrantz; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stereochemis; bicyclooctanes.Transamination; complexation; cyclodextrins; proton transfer; hydride transfer; stereochemistry; Transamination; Organic chemistry; Organisk kemi;

    Sammanfattning : Two new transamination systems are described. The first example is a dibenzo[a,d]- cycloheptene containing system, designed to accomplish a [1,3]-hydride transfer. Several catalysts have been examined for this purpose. tris-Pentafluorophenyl borane was found to be the most efficient catalyst. LÄS MER

  4. 3. Functional studies of a membrane-anchored cellulase from poplar

    Författare :Ulla Jonsson Rudsander; Tuula Teeri; Eva Nordberg-Karlsson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Populus; cellulose biosynthesis; endo-1; 4-b-glucanase; cellulase; Pichia pastoris; Arabidopsis thaliana; NMR spectroscopy; cleavage pattern; stereochemistry; transglycosylation; complementation; hybrid proteins; overexpression; substrate analysis; overglycosylation; Bioengineering; Bioteknik;

    Sammanfattning : Cellulose in particular and wood in general are valuable biomaterials for humanity, and cellulose is now also in the spotlight as a starting material for the production of biofuel. Understanding the processes of wood formation and cellulose biosynthesis could therefore be rewarding, and genomics and proteomics approaches have been initiated to learn more about wood biology. LÄS MER

  5. 4. Stereoselectivity in organic chemistry : asymmetric 1,3-dipolar cycloadditions and rule-based conformational analysis

    Författare :Kaye Stern; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; molecular mechanics; nitrile oxides; Stereochemistry; nitrone;

    Sammanfattning : .... LÄS MER

  7. 5. 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