Kristian Sørnes

• Slapkaras, Petros Danielsen; Sørnes, Kristian; Nolsøe, Jens Mortansson Jelstrup; Ekholm, Filip; Solum, Eirik Johansson & Aursnes, Marius (2026). Palladium catalyzed cross-couplings of trans-vinylboranes with alkyl bromides: a reversed-polarity alternative to B-alkyl Suzuki reactions. Organic and biomolecular chemistry. ISSN 1477-0520. doi: 10.1039/d6ob00314a. Fulltekst i vitenarkiv
• Hoel, Håvard; Carvalho, Mariana Mazetto de; Fu, Yu Ping; Chan, Emily; Hamre, Anne Grethe & Sørnes, Kristian [Vis alle 9 forfattere av denne artikkelen] (2026). Comprehensive structural characterization of pectin, arabinan and galactan from Gentiana purpurea L. roots and their immunostimulatory effects. Carbohydrate Polymer Technologies and Applications. 14. doi: 10.1016/j.carpta.2026.101117. Fulltekst i vitenarkiv Vis sammendrag

  The roots of Gentiana purpurea L. have historically been an important herbal drug in Norwegian folk medicine. Due to its content of bitter compounds, it was used to treat digestive ailments, but it was also boiled in water for use against infections. Previous work has shown promising immunostimulatory effects of a polysaccharide enriched fraction from G. purpurea, and therefore the aim of this present study was to further isolate and characterize these polysaccharides and investigate their immunogenic properties. One acidic polysaccharide fraction (Gentiana Purpurea Acidic Polysaccharides, GP-AP) and one neutral (Gentiana Purpurea Neutral Polysaccharides, GP-NP) were isolated by anion-exchange chromatography from the ethanol precipitate of G. purpurea root water extract, and their structures were characterized by SEC-MALS, GC, GC–MS and NMR. GP-AP was shown to contain pectin type structures such as homogalacturonan and rhamnogalacturonan type I backbones, as well as neutral structures such as arabinogalactan type I and highly branched arabinans. GP-NP had similar neutral polysaccharides as GP-AP, with high amounts of highly branched arabinans. GP-AP was able to cause an immunostimulatory response in J774.A1 macrophages, likely partly through interaction with TLR 4, whilst GP-NP was inactive.

• Uhlig, Silvio; So̷rnes, Kristian; Mineeva, Evangeliia; Rise, Frode; Grutle, Lene & Morisbak, Else [Vis alle 9 forfattere av denne artikkelen] (2025). Nucleophilic Addition of Thiols to Methacrylates for Biomedical Applications Revisited. Chemical Research in Toxicology. ISSN 0893-228X. 38(9), s. 1535–1547. doi: 10.1021/acs.chemrestox.5c00179. Fulltekst i vitenarkiv Vis sammendrag

  Composites are popular materials for, among others, restorative dentistry because of their favorable mechanical and esthetic properties and direct-filling applications. The raw materials for such composites usually consist of filler particles embedded in a matrix of dimethacrylate monomers that are polymerized in situ. Because the raw materials cannot polymerize completely, residual monomers leach out over time. The conjugation of methacrylates with sulfur compounds has been recognized as an important reaction as well as a detoxification pathway; thus, leached monomers are expected to undergo chemical reactions with various biomolecules that contain thiol functionalities. To understand the reaction of dental methacrylate monomers with thiols, we studied the reaction of 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate, urethane dimethacrylate, and bisphenol A diglycidyl methacrylate with the model thiol 2-mercaptoethanol using liquid chromatography coupled to low- and high-resolution mass spectrometry (LC–MS and LC–HRMS). The results indicate that thiols react readily with the conjugated double bond, and with methacrylate half-lives of 7–21 h under pseudo-first-order reaction conditions and at neutral pH. Dimethacrylates first formed a monoaddition product, while thiol addition to the second acrylate moiety was observed on a longer time scale. The reaction of HEMA with l-cysteine and l-glutathione was studied in more detail using HRMS and NMR spectroscopy. The reaction rates were substantially higher than for the reaction with mercaptoethanol, and NMR analysis revealed the presence of two isomeric reaction products. Structural characterization also included the identification and assignment of sulfoxides of HEMA-cysteine and HEMA-glutathione. Using the characterized HEMA–thiols as reference standards for LC–HRMS, we demonstrated the presence of HEMA-glutathione, HEMA-cysteine, their sulfoxides, and a putative HEMA-cysteinylglycine in a human osteoblast-like cell line following exposure to HEMA.

• Hassel, Bjørnar; Sørnes, Kristian; Elsais, Ahmed; Cordero, Patricia Reyes; Frøland, Anne-Sofie & Rise, Frode (2024). Glyceraldehyde metabolism in mouse brain and the entry of blood-borne glyceraldehyde into the brain. Journal of Neurochemistry. ISSN 0022-3042. doi: 10.1111/jnc.16158. Fulltekst i vitenarkiv Vis sammendrag

  D-Glyceraldehyde, a reactive aldehyde metabolite of fructose and glucose, is neurotoxic in vitro by forming advanced glycation end products (AGEs) with neuronal proteins. In Alzheimer's disease brains, glyceraldehyde-containing AGEs have been detected intracellularly and in extracellular plaques. However, little information exists on how the brain handles D-glyceraldehyde metabolically or if glyceraldehyde crosses the blood–brain barrier from the circulation into the brain. We injected [U-13C]-D-glyceraldehyde intravenously into awake mice and analyzed extracts of serum and brain by 13C nuclear magnetic resonance spectroscopy. 13C-Labeling of brain lactate and glutamate indicated passage of D-glyceraldehyde from blood to brain and glycolytic and oxidative D-glyceraldehyde metabolism in brain cells. 13C-Labeling of serum glucose and lactate through hepatic metabolism of [U-13C]-D-glyceraldehyde could not explain the formation of 13C-labeled lactate and glutamate in the brain. Cerebral glyceraldehyde dehydrogenase and reductase activities, leading to the formation of D-glycerate and glycerol, respectively, were 0.27–0.28 nmol/mg/min; triokinase, which phosphorylates D-glyceraldehyde to D-glyceraldehyde-3-phosphate, has been demonstrated previously at low levels. Thus, D-glyceraldehyde metabolism toward glycolysis could proceed both through D-glycerate, glycerol, and D-glyceraldehyde-3-phosphate. The aldehyde group of D-glyceraldehyde was overwhelmingly hydrated into a diol in aqueous solution, but the diol dehydration rate greatly exceeded glyceraldehyde metabolism and did not restrict it. We conclude that (1) D-glyceraldehyde crosses the blood–brain barrier, and so blood-borne glyceraldehyde could contribute to AGE formation in the brain, (2) glyceraldehyde is taken up and metabolized by brain cells. Metabolism thus constitutes a detoxification mechanism for this reactive aldehyde, a mechanism that may be compromised in disease states.

• Berntsen, Linn Neerbye; Solvi, Thomas Nordbø; Sørnes, Kristian; Wragg, David Stephen & Sandtorv, Alexander Harald (2021). Cu-catalyzed C(sp2)-N-bond coupling of boronic acids and cyclic imides. Chemical Communications. ISSN 1359-7345. 57(89), s. 11851–11854. doi: 10.1039/d1cc04356k. Fulltekst i vitenarkiv

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• Wang, Xinhui; Solhaug, Anita; Mudge, Elizabeth M.; Garrido, Bruno C.; Fon, Mathias & Andersen, Aaron [Vis alle 14 forfattere av denne artikkelen] (2025). Leadbeaterins, novel ichthyotoxic sterolysins from the haptophyte Chrysochromulina leadbeateri, responsible for massive fish kills in Norway. Fulltekst i vitenarkiv
• Sørnes, Kristian & Sandtorv, Alexander Harald (2021). Altering the structural elements of indole-based PDF inhibitors: Synthesis and characterisation. Universitetet i Oslo. Fulltekst i vitenarkiv Vis sammendrag

  Indole-based hydroaxmic acids have previously been shown to selectively inhibit bacterial peptide deformylase (PDF), a metalloenzyme that cleaves off formyl the N-terminal end of newly formed proteins. Amino acid formylation and subsequent deformylation make up a set of processes that are crucial for bacterial growth and redundant in human cells, making PDF an intriguing antibacterial target. Inhibition of PDF represents a novel mode of action that is yet to be exploited by commercial antibiotics, something that is desparately needed in the fight against antimicrobial resistance. The existence of a human mitochondrial PDF has been a source of concern despite its role in normal cell function being largely unknown. Inhibitors that are selective towards bacterial PDF are therefore of major interest. Indole-based inhibitors are said to achieve selectivity through their central indole scaffold, which is reportedly too bulky to fit the active site of human PDF. No justification for the indole fragment has been given apart from its apparent size, raising questions around which exact structural elements are needed for selective inhibition. In this study, we sought to synthesise analogues of indole-based inhibitors with certain structural elements altered, intending to explore potential enzyme interactions that may or may not be important for inhibition. The central scaffold became the main focus of the study, for which four different synthetic routes were designed. The four target molecules included an indole benchmark and its corresponding benzimidazole, benzotriazole, and indene equivalents. Of these, only the indole and indene targets were successfully synthesised. The indole structure could be formed at poor yields using a reported procedure, while the indene structure required careful handling of a dynamic endo/exo-isomerisation. Major steps were made in the syntheses of the benzimidazole and benzotriazole targets, with both scaffolds successfully being formed as intended. Ultimately, the designed routes failed at incorporating the needed hydroxamic acid functionality. The indole and indene inhibitors remain to be tested for inhibitory activity. Future studies should focus on biochemical testing of the synthesised structures, as well as redoing the benzimidazole and benzotriazole routes using water-insoluble peptide coupling reagents in the final step. Preliminary studies were made on the formation of indolyl and indenyl hydrazides, although more purification is needed. Suggested synthetic routes for indane, naphthalene, pyridine, and thiohydoxamic acid targets are provided.

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