Search for dissertations about: "aromatic acids"

Showing result 1 - 5 of 78 swedish dissertations containing the words aromatic acids.

2. 1. Synthesis of aromatic bis- and tris(amino acids) and chiral dendrimers

   Author : Andreas Ritzén; Centrum för analys och syntes; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organisk kemi; Organic chemistry; HWE reaction; asymmetric hydrogenation; Heck reaction; Amino acids; chiral dendrimers;

   Abstract : A number of protected aromatic bis- and tris(amino acids) have been synthesised by catalytic asymmetric hydrogenation of the corresponding didehydroamino acid derivatives. The didehydroamino acid derivatives were prepared either by a Heck coupling of a 2-amidoacrylate with an aryl dihalide, or by Horner-Wadsworth-Emmons olefination of aromatic aldehydes with phosphonylglycine reagents. READ MORE

4. 2. Structural and Biophysical Studies of Nucleic Acids

   Author : Wimal Pathmasiri; Adolf Gogoll; Lena Mäler; Uppsala universitet; []
   Keywords : Organic chemistry; nucleic acids; Nuclear Magnetic Resonance; molecular dynamics; sugar modified nucleosides; pKa; Organisk kemi;

   Abstract : This thesis is based on six research publications concerned with (i) study of the molecular structures and dynamics of modified nucleosides; (ii) investigation of the effect of incorporation of modified nucleosides on the structure of DNA; (iii) examination of the effect of the sugar modifications on the pseudo-aromatic properties (pKa) of the nucleobases; (iv) analysis of the effect of the CH-π interactions on the relative stability of the DNA-RNA hybrid duplexes. The structural stability of the nucleic acids as well as their behavior in molecular recognition is dominated by hydrogen bonding and stacking interactions beside other non-covalent interactions. READ MORE

5. 3. Mass Spectrometry of Biologically Active Small Molecules : Focusing on polyphenols, alkaloids and amino acids

   Author : Zdeněk Spáčil; Leopold L. Ilag; Frantisek Turecek; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; LC-MS; LDI; Mass spectrometry; HPLC; UHPLC; polyphenols; phenolic acids; BMAA; Separation methods; Separationsmetoder; Analytical chemistry; Analytisk kemi; Analytical Chemistry; analytisk kemi;

   Abstract : The foci of this dissertation are on advanced liquid chromatography (LC) separation and mass spectrometry (MS) techniques for the analysis of small bioactive molecules. In addition to discussing general aspects of such techniques the results from analyses of polyphenols (PPs), alkaloids and amino acids published in five appended studies are presented and discussed. READ MORE

6. 4. Non Natural Aromatic Amino Acids Applications in cage-construction, metal ion coordination and asymmetric catalysis

   Author : Ruxandra Ionescu; Centrum för analys och syntes; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; diethylzinc additions.; spectroscopy; metal ion coordination; cage-like compounds; Amino acids; C3-symmetry; Organic chemistry; Organisk kemi;

   Abstract : Aromatic non-natural amino acids, the outstanding feature of which was the presence of several arms, were synthesised and their properties investigated. The amino acids were synthesised following a standard procedure starting with a Horner-Wadsworth-Emmons or a Heck reaction, which provided didehydroamino acids. READ MORE

7. 5. Synthesis of Non-Natural Aromatic Amino Acids Derivatives Solvent-free reactions-Versatile building blocks-Galectin inhibitors

   Author : Erik Tullberg; Centrum för analys och syntes; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Organisk kemi; Organic chemistry; Naturvetenskap; Natural science; Multivalent galectin inhibitors; Multifunctional molecules; Amino Acids; Solvent-free reactions;

   Abstract : This thesis deals with three topics concerning the synthesis of non-natural also known as unnatural amino acid derivatives. In the first, solvent-free reaction conditions for the Heck reaction were developed that were superior to previous conditions because the reaction time could be reduced and the work-up procedure simplified. READ MORE