| 1. |
- Anderson, Orlagh, et al.
(författare)
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An investigation of the antileishmanial properties of semi-synthetic saponins
- 2020
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Ingår i: RSC MEDICINAL CHEMISTRY. - : Royal Society of Chemistry (RSC). - 2632-8682. ; 11:7, s. 833-842
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Tidskriftsartikel (refereegranskat)abstract
- Leishmaniasis is a neglected tropical disease caused by insect-vector borne protozoan parasites of the,Leishmania species. Whilst infection threatens and affects millions of the global poor, vaccines are absent and drug therapy limited. Extensive efforts have recently been made to discover new leads from small molecule synthetic compound libraries held by industry; however, the number of new chemical entities identified and entering development as anti-leishmanials has been very low. This has led to increased interest in the possibility of discovering naturally derived compounds with potent antileishmanial activity which may be developed towards clinical applications. Plant-derived triterpenoid and steroidal saponins have long been considered as anti-microbials and here we describe an investigation of a library of 137 natural (9) and semi-synthetic saponins (128) for activity againstLeishmania mexicana, a causative agent of cutaneous leishmaniasis. The triterpenoid sapogenin, hederagenin, readily obtained in large quantities fromHedera helix(common ivy), was converted into a range of 128 derivatives. These semi-synthetic compounds, as well as saponins isolated from ivy, were examined with a phenotypic screening approach to identify potent and selective anti-leishmanial hits. This led to the identification of 12 compounds, including the natural saponin gypsogenin, demonstrating high potency (ED50< 10.5 mu M) against axenicL. mexicanaamastigotes, the mammalian pathogenic form. One of these, hederagenin disuccinate, was sufficiently non-toxic to the macrophage host cell to facilitate further analyses, selectivity index (SI) > 10. Whilst this was not active in an infected cell model, the anti-leishmanial properties of hederagenin-derivatives have been demonstrated, and the possibility of improving the selectivity of natural hederagenin through chemical modification has been established.
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| 2. |
- Andersson, Claes-Henrik, et al.
(författare)
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Reversible non-covalent derivatisation of carbon nanotubes with glycosides
- 2009
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Ingår i: Soft Matter. - : Royal Society of Chemistry (RSC). - 1744-683X .- 1744-6848. ; 5:14, s. 2713-2716
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Tidskriftsartikel (refereegranskat)abstract
- SWNTs and MWNTs have been non-covalently functionalized with glycosides in a reversible manner, and fluorescence titrations have been used to quantify the formed supramolecular assemblies which for SWNTs exhibits increased water solubility.
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| 3. |
- Andre, Sabine, et al.
(författare)
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Glycocluster Design for Improved Avidity and Selectivity in Blocking Human Lectin/Plant Toxin Binding to Glycoproteins and Cells
- 2010
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Ingår i: Molecular Pharmaceutics. - : American Chemical Society (ACS). - 1543-8384 .- 1543-8392. ; 7:6, s. 2270-2279
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Tidskriftsartikel (refereegranskat)abstract
- Blocking lectin/toxin binding to human cells by suitable inhibitors can therapeutically protect them from harmful effects. Clustered design of ligand presentation holds the promise of affinity increase relative to the free sugar and inherent selectivity among lectin targets. Using first a solid-phase assay with a glycoprotein presenting N-glycans as lectin-reactive probe, we assessed the inhibitory potency of bi- to tetravalent clusters on a plant toxin and three human adhesion/growth-regulatory lectins. Enhanced avidity relative to the free sugar was detected together with lectin-type selectivity. These effects were confirmed on the level of cells in vitro, also for two leguminous lectins. The lack of toxicity in cell proliferation assays excluded concerns to further work on these compounds. The given cluster design and the strategic combination of the two assay systems of increasing biorelevance will thus be helpful to take the next steps in drug development, e.g. tailoring the sugar headgroup.
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| 4. |
- Arewang, Carl Johan, et al.
(författare)
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Synthesis of urine drug metabolites : glucuronic acid glycosides of phenol intermediates
- 2007
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Ingår i: Carbohydrate Research. - : Elsevier BV. - 0008-6215 .- 1873-426X. ; 342:7, s. 970-974
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Tidskriftsartikel (refereegranskat)abstract
- The investigation of drug metabolism requires substantial amount of metabolites. Isolation from urine is tedious, therefore, the material obtained by synthesis is preferred. Substantial amounts of three tentative drug metabolites, phenolic glucuronides, have been prepared using easily available glycosyl donors. The final products [3(2-N-methyl-N-isopropylaminoethoxy)phenyl] beta-D-glucopyranosiduronic acid, 4-amino-3,5-dimethylphenyl beta-D-glucopyranosiduronic acid and [2(S)-propanoyl-6-O-naphthyl] beta-D-glucopyranuronic acid are useful as, for example, reference material in metabolite investigations.
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| 5. |
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| 6. |
- Aspholm-Hurtig, Marina, et al.
(författare)
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Functional adaptation of BabA, the H. pylori ABO blood group antigen binding adhesin.
- 2004
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Ingår i: Science (New York, N.Y.). - : American Association for the Advancement of Science (AAAS). - 1095-9203 .- 0036-8075. ; 305:5683, s. 519-22
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Tidskriftsartikel (refereegranskat)abstract
- Adherence by Helicobacter pylori increases the risk of gastric disease. Here, we report that more than 95% of strains that bind fucosylated blood group antigen bind A, B, and O antigens (generalists), whereas 60% of adherent South American Amerindian strains bind blood group O antigens best (specialists). This specialization coincides with the unique predominance of blood group O in these Amerindians. Strains differed about 1500-fold in binding affinities, and diversifying selection was evident in babA sequences. We propose that cycles of selection for increased and decreased bacterial adherence contribute to babA diversity and that these cycles have led to gradual replacement of generalist binding by specialist binding in blood group O-dominant human populations.
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| 7. |
- Bernardi, Anna, et al.
(författare)
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Multivalent glycoconjugates as anti-pathogenic agents
- 2013
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Ingår i: Chemical Society Reviews. - : Royal Society of Chemistry (RSC). - 0306-0012 .- 1460-4744. ; 42:11, s. 4709-4727
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Forskningsöversikt (refereegranskat)abstract
- Multivalency plays a major role in biological processes and particularly in the relationship between pathogenic microorganisms and their host that involves protein-glycan recognition. These interactions occur during the first steps of infection, for specific recognition between host and bacteria, but also at different stages of the immune response. The search for high-affinity ligands for studying such interactions involves the combination of carbohydrate head groups with different scaffolds and linkers generating multivalent glycocompounds with controlled spatial and topology parameters. By interfering with pathogen adhesion, such glycocompounds including glycopolymers, glycoclusters, glycodendrimers and glyconanoparticles have the potential to improve or replace antibiotic treatments that are now subverted by resistance. Multivalent glycoconjugates have also been used for stimulating the innate and adaptive immune systems, for example with carbohydrate-based vaccines. Bacteria present on their surfaces natural multivalent glycoconjugates such as lipopolysaccharides and S-layers that can also be exploited or targeted in anti-infectious strategies.
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| 8. |
- Bonnardel, Francois, et al.
(författare)
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Architecture and Evolution of Blade Assembly in beta-propeller Lectins
- 2019
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Ingår i: Structure. - : Elsevier BV. - 0969-2126 .- 1878-4186. ; 27:5, s. 764-
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Tidskriftsartikel (refereegranskat)abstract
- Lectins with a beta-propeller fold bind glycans on the cell surface through multivalent binding sites and appropriate directionality. These proteins are formed by repeats of short domains, raising questions about evolutionary duplication. However, these repeats are difficult to detect in translated genomes and seldom correctly annotated in sequence databases. To address these issues, we defined the blade signature of the five types of beta-propellers using 3D-structural data. With these templates, we predicted 3,887 beta-propeller lectins in 1,889 species and organized this information in a searchable online database. The data reveal a widespread distribution of beta-propeller lectins across species. Prediction also emphasizes multiple architectures and led to the discovery of a beta-propeller assembly scenario. This was confirmed by producing and characterizing a predicted protein coded in the genome of Kordia zhangzhouensis. The crystal structure uncovers an intermediate in the evolution of beta-propeller assembly and demonstrates the power of our tools.
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| 9. |
- Bouillon, Marc E., et al.
(författare)
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Synthesis of Anemoclemosides A and B, Two Saponins Isolated from Anemoclema glaucifolium
- 2020
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Ingår i: European Journal of Organic Chemistry. - : Wiley. - 1434-193X .- 1099-0690. ; 2020:48, s. 7470-7473
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Tidskriftsartikel (refereegranskat)abstract
- Steroidal and triterpenoid saponins are attractive for their wide-ranging pharmacological properties. The triterpenoid saponins Anemoclemoside A and B are root constituents of the Chinese folk medicinal plant Anemoclema glaucifolium (Ranunculaceae). Both compounds feature an unusual cyclic acetal linkage to the carbohydrate l-arabinose in its open chain form rather than the typical glycosidic bond present in normal saponins. The straightforward and scalable syntheses of both saponins starting from l-arabinose as well as l-lyxose and l-rhamnose are described.
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| 10. |
- Boysen, Mike, et al.
(författare)
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Ethyl 2-acetamido-4,6-di-O-benzyl-2,3-N,O-carbonyl-2-deoxy-1-thio-beta-D-glycopyranoside as a versatile GlcNAc donor.
- 2005
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Ingår i: Chemical communications (Cambridge, England). - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; :24, s. 3044-6
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Tidskriftsartikel (refereegranskat)abstract
- The title donor, ethyl 2-acetamido-4,6-di-O-benzyl-2,3-N,O-carbonyl-2-deoxy-1-thio-beta-D-glycopyranoside, is shown to be an excellent glycosyl donor giving immediate and efficient access to variant GlcNAc-containing oligosaccharides.
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