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Now showing items 4297-4316 of 4765
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Synergy between Experimental and Computational Approaches to Homogeneous Photoredox Catalysis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-06-03)In this Frontiers article, we highlight how state-of-the-art density functional theory calculations can contribute to the field of homogeneous photoredox catalysis. We discuss challenges in the fields and potential solutions to be found at the interface between theory and experiment. The exciting opportunities and insights that can arise through such an interdisciplinary approach are highlighted. -
A Synergy of Artificial Bee Colony and Genetic Algorithms to Determine the Parameters of the Σ-Gram Distance
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014)In a previous work we presented the Σ-gram distance that computes the similarity between two sequences. This distance includes parameters that we calculated by means of an optimization process using artificial bee colony. In another work we showed how population-based bio-inspired algorithms can be sped up by applying a method that utilizes a pre-initialization stage to yield an optimal initial ... -
Synoptic Variability in Satellite Altimeter-Derived Radar Freeboard of Arctic Sea Ice
(Journal article; Tidsskriftartikkel; Peer reviewed, 2023-01-09)Satellite observations of sea ice freeboard are integral to the estimation of sea ice thickness. It is commonly assumed that radar pulses from satellite-mounted Ku-band altimeters penetrate through the snow and reflect from the snow-ice interface. We would therefore expect a negative correlation between snow accumulation and radar freeboard measurements, as increased snow loading weighs the ice floe ... -
Syntese av klorerte fettsyrer til bruk som standarder i miljøanalyser
(Master thesis; Mastergradsoppgave, 2007-06-20)Mettede C-16 og C-18 klorerte fettsyrer ble syntetisert til bruk som miljøstandarder. De mettede klorerte fettsyrene hører sammen med en ny type miljøgift nemlig klorerte fettsyrer (ClFA). Dette er en type miljøgift som man per dags dato ikke har så mye kunnskap om, men som er blitt påvist i en rekke forskjellige fiskearter. Hvilken effekt de vil ha på mennesker eller andre pattedyr på toppen av ... -
Synthesis and biological evaluation of new dipicolylamine zinc chelators as metallo-β-lactamase inhibitors
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-02-02)Antibiotics are key drugs in modern healthcare, especially in hospitals, where multiresistant bacteria resides and is a potential threat to human health. In the present work, a new series of adjuvants working synergistically with the carbapenem meropenem, in which a selective zinc-chelating agent was covalently linked to the small bacterial peptide D-Ala-D-Ala, was synthesized and tested against ... -
Synthesis and inhibitor design of carbapenemase inhibitors
(Doctoral thesis; Doktorgradsavhandling, 2018-05-24)The efficiency of bacteria in acquiring resistance for their survival ensures a never-ending war against resistance. The only tactic to curtail the resistance crisis is to keep pace with it, e.g. by continuous development of new antibiotics with activity against resistant bacteria or revival of existing agents by inhibiting the mechanisms of resistance. β-lactams are the largest and most widely used ... -
Synthesis and Molecular Structure of a Copper Octaiodocorrole
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-05-09)Although rather delicate on account of their propensity to undergo deiodination, β-octaiodoporphyrinoids are of considerable interest as potential precursors to novel β-octasubstituted macrocycles. Presented herein are early results of our efforts to synthesize β-octaiodocorrole derivatives. Oxidative condensation of 3,4-diiodopyrrole and aromatic aldehydes failed to yield free-base octaiodocorroles. ... -
Synthesis and molecular structure of perhalogenated rhenium-oxo corroles
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-12)As part of our efforts to develop rhenium-oxo corroles as photosensitizers for oxygen sensing and photodynamic therapy, we investigated the potential <i>β</i>-perhalogenation of five ReO <i>meso</i>-tris(<i>para</i>-X-phenyl)corroles, Re[T<i>p</i>XPC](O) (X = CF<sub>3</sub>, H, F, CH<sub>3</sub>, and OCH<sub>3</sub>), with elemental chlorine and bromine. With Cl<sub>2</sub>, <i>β</i>-octachlorinated ... -
Synthesis of 5,7-diarylindoles via Suzuki-Miyaura coupling in water
(Journal article; Tidsskriftartikkel; Peer reviewed, 2021-11-16)The synthesis of novel 5,7-diaryl and diheteroaryl indoles has been explored via efficient double Suzuki–Miyaura coupling. The method notably employs a low catalyst loading of Pd(PPh<sub>3</sub>)<sub>4</sub> (1.5 mol%/coupling) and water as the reaction solvent to obtain 5,7-diarylated indoles without using N-protecting groups in up to 91% yield. The approach is also suitable for N-protected and ... -
Synthesis of 5-,6-, and 7-membered heterocycles from barbituric acid derivatives
(Master thesis; Mastergradsoppgave, 2011-06-10)SUMMARY A new procedure has been developed for the synthesis of barbituric acid derivatives. The reactions were performed under solvent free conditions without any catalyst. Employing this synthetic route, a large number of chalconoids and 5-,6-, and 7-membered heterocycles have been successfully synthesized in a very short time. The chalconoids have been synthesized from a barbituric derivative ... -
Synthesis of a novel class of antitubercular peptidomimetics based on β-aminoboronates.
(Doctoral thesis; Doktorgradsavhandling, 2012-11-16)The unique properties of antimicrobial peptides have attracted the attention of chemists since the 1970’s. This class of compounds provides additional tools in the treatment of infections and the work described in this thesis was therefore focused on the synthesis of short peptidomimetics on the basis of modified amino acids and evaluation of their antimicrobial activity. The compounds of choice ... -
Synthesis of Indoles and Pyrroles Utilizing Iridium Carbenes Generated from Sulfoxonium Ylides
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-03-20)Metal carbenes can undergo a myriad of synthetic transformations. Sulfur ylides are potential safe precursors of metal carbenes. Herein, we report cascade reactions that involve carbenoids derived from sulfoxonium ylides for the efficient and regioselective synthesis of indoles and pyrroles. The tandem action of iridium and Brønsted acid catalysts enables rapid assembly of the heterocycles from ... -
Synthesis of phorbazoles and breitfussins analogues
(Master thesis; Mastergradsoppgave, 2016-05-18)Breitfussins are a group of a closely related heterocyclic compounds. They consist of a tetracyclic structure with an indole, an oxazole and a pyrrole. The breitfussins exhibit interesting biological activity and analogues synthesis and biological evaluation is ongoing. Phorbazoles have a structural similarity with breitfussins in which a phenol replaces the indole. As a part of this, synthesis of ... -
Synthesis of Potential Metallo-beta-Lactamase Inhibitors
(Master thesis; Mastergradsoppgave, 2011-11-15) -
Synthesis of Potential Metallo-β-Lactamase Inhibitors
(Master thesis; Mastergradsoppgave, 2012-06-04)Oppgaven omhandler syntesen av mulige metallo-beta-lactamaser inhibitorer. -
Synthesis of Sterically Hindered Macrocyclic Ligands via Demetalation of Metallocorroles
(Doctoral thesis; Doktorgradsavhandling, 2016-06-07)Despite important developments in synthetic corrole chemistry, the field has long been handicapped by the lack of procedures for demetalation of metallocorroles. This thesis presents general demetalation methods for metallocorroles. A reductive demetalation method was developed using concentrated H2SO4 with 5-200 equivalent of FeCl2 or SnCl2 as a reducing agent. The method proved to be quite general ... -
Synthesis of thiol-appended gold and rhenium corroles as potential nanoconjugants for gold nanoparticles
(Master thesis; Mastergradsoppgave, 2023-06-10)Photodynamic therapy (PDT) today is an established treatment for a variety of cancers as well as various dermatological conditions, macular degeneration and bacterial and other infections. Treatment involves the administration of a photosensitizer, typically a porphyrin, followed by irradiation with light. The photoexcited sensitizer transfers its excess energy to oxygen in the affected tissue, ... -
Synthesis of XTH inhibitors
(Master thesis; Mastergradsoppgave, 2019-05-15)XTH er en gruppe enzymer som ble oppdaget tidlig på 90 tallet og muligens er involvert i Cuscuta infeksjonen av tomater. En nylig studie gjort ved arktisk og marin biologi UIT viser at Brilliant Blue R250 fungerer som en god inhibitor mot disse enzymene. I dette prosjektet ble det fokusert på å syntetisere strukturelt like molekyler for å potensielt øke vannløseligheten og inhibitoraktiviteten. ... -
Synthesis of β-substituted β-aminoboronates
(Master thesis; Mastergradsoppgave, 2013-05)Recent work at the University of Tromsø has uncovered new α-substituted α- and β-aminoboron containing peptidomimetics that shows antimicrobial, antifungal and antitubercular activity in addition to kinase inhibition and promotion. As a continuation of this work a new approach for the synthesis of β-substituted β-aminoboronates has been developed. The approach involves the non-stereospecific ... -
Synthesis, Spectroscopy, Electrochemistry and DFT of Electron-Rich Ferrocenylsubphthalocyanines
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-06-01)A series of novel ferrocenylsubphthalocyanine dyads Y-BSubPc(H)<sub>12</sub> with ferrocenylcarboxylic acids Y-H = (FcCH<sub>2</sub>CO<sub>2</sub>-H), (Fc(CH<sub>2</sub>)<sub>3</sub>CO<sub>2</sub>-H) or (FcCO(CH<sub>2</sub>)<sub>2</sub>CO<sub>2</sub>-H) in the axial position were synthesized from the parent Cl-BSubPc(H)<sub>12</sub> via an activated triflate-SubPc intermediate. UV/Vis data revealed ...
