Sökning: "SNAr reaction"

Hittade 4 avhandlingar innehållade orden SNAr reaction.

  1. 1. Synthesis of β-turn and pyridine based peptidomimetics

    Författare :David Blomberg; Jan Kihlberg; Kay Brickmann; Torbjörn Frejd; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Peptidomimetics; beta-turn; beta-strand; pyridine scaffold; Grignard exchange reaction; SNAr reaction; thrombin inhibitor; Leu-enkephalin.; Organic synthesis; Organisk syntes;

    Sammanfattning : Despite the unfavorable pharmacokinetic properties associated with peptides, they are still of great interest in drug development due to a multitude of interesting biological functions. The development of peptidomimetics strives to maintain or improve the biological activity of a peptide concurrently with removing the unwanted properties. LÄS MER

  3. 2. Quantum Chemical Studies of Aromatic Substitution Reactions

    Författare :Magnus Liljenberg; Tore Brinck; Leif Eriksson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Teoretisk kemi och biologi; Theoretical Chemistry and Biology;

    Sammanfattning : In this thesis, density functional theory (DFT) is used to investigate the mechanisms and reactivities of electrophilic and nucleophilic aromatic substitution reactions (SEAr and SNAr respectively). For SEAr, the σ-complex intermediate is preceded by one (halogenation) or two (nitration) π-complex intermediates. LÄS MER

  4. 3. Redesign of substrate specificity of glutathione transferase and glutathione reductase : Enzyme engineering by directed mutagenesis, phage-display selection and DNA shuffling

    Författare :Lars O. Hansson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Biokemi; Biochemistry; Biokemi; biokemi; Biochemistry;

    Sammanfattning : Human glutathione transferase (GST) A1-1 was expressed in fusion with the phage gene IIIproduct and a library of phage-displayed GST mutants was constructed by randomization of fouractive-site residues. Variant GSTs were isolated by mechanism-based phage display selection, using an immobilized transition-state analog of a nucleophilic aromatic substitution (SNAr) reaction. LÄS MER

  5. 4. New Reactivity in Diaryliodonium Salt Chemistry

    Författare :Erika Linde; Berit Olofsson; Thomas Wirth; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic Chemistry; organisk kemi;

    Sammanfattning : Diaryliodonium salts (Ar2IX) have emerged as versatile multi-purpose reagents with desirable properties such as easy accessibility, low toxicity and applicability under mild and metal-free reaction conditions. Despite displaying broad utility in arylations of both carbon and heteroatom nucleophiles, the overall sustainability of these protocols is compromised by featuring poor atom economy due to the formation of stochiometric iodoarene byproducts. LÄS MER