References of "Thonon, David"
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See detailNew Strategy for the Preparation of Clickable Peptides and Labeling with 1-(Azidomethyl)-4-[18F]-fluorobenzene for PET
Thonon, David ULg; Paris, Jérôme ULg; Kech, Cecile et al

in Bioconjugate Chemistry (2009), 20(4), 817-823

The alkyne-azide Cu(I)-catalyzed Huisgen cycloaddition, a click type reaction was used to label a peptide with fluorine-18. A novel solid phase synthesis approach for the preparation of clickable peptides ... [more ▼]

The alkyne-azide Cu(I)-catalyzed Huisgen cycloaddition, a click type reaction was used to label a peptide with fluorine-18. A novel solid phase synthesis approach for the preparation of clickable peptides has been developed and has also permitted the straightforward preparation of reference compounds. A complementary azide labeling agent (1-(azidomethyl)-4-[18F]-fluorobenzene) has been produced in a four step procedure in 75 min with a 34% radiochemical yield (decay corrected). Conjugation of [18F]fluoroazide with a model alkyne-neuropeptide produced the desired 18F-radiolabeled peptide in less than 15 min with a yield of 90% and excellent radiochemical purity [less ▲]

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See detailClick chemistry : radiolabelling of oligonucleotides with fluorine-18 for PET imaging
Kaisin, Geoffroy ULg; Flagothier, Jessica ULg; Mercier, Frédéric et al

Poster (2009, March 18)

Click chemistry : radiolabelling of oligonucleotides with fluorine-18 for PET imaging Oligonucleotides (ONs), especially small interfering RNA (siRNA), are promising therapeutic agents, but their ... [more ▼]

Click chemistry : radiolabelling of oligonucleotides with fluorine-18 for PET imaging Oligonucleotides (ONs), especially small interfering RNA (siRNA), are promising therapeutic agents, but their pharmacokinetics and biodistributions are widely unknown. Positron Emission Tomography (PET) using fluorine-18 is a suitable technique to image and quantify such biological processes. The challenge for the radiochemist is to introduce this short half-life isotope (t1/2(18F)=109.7 min) onto oligonucleotides or, more generally, biomolecules. The most common technique requires the coupling of a prosthetic group bearing the radiotracer with the biomolecule. Current methods for labeling ONs with fluorine-18 have sub-optimal yields and require a long synthesis time.{Vries2003} Click chemistry, e.g. 1,3-dipolar Huisgen cycloaddition of azides to alkynes, could be an efficient way to increase yields and reduce synthesis time (see Figure 1). This family of reactions are well suited to the radiolabelling of ONs as they are tolerant to a wide range of solvent and require mild reaction conditions and simple purifications.{Glaser2007} The major strength of this approach is its versatility: it can be easily transposed to any other kind of biomolecules (e.g. peptides, lipids) as long as they can bear an azido or alkyne moiety. Conjugations with ONs are usually performed at 3’-ends using a well-chosen linker in order to limit degradation by exonucleases and to avoid alteration of hybridization properties and siRNA gene silencing efficiency.{Kurreck2009} This also allows the development of universal solid support because synthesis occurs from the 3’ to 5’-end. The linker must fulfil a number of requirements:{Gait2001} - Bearing one alkyne, one primary and one secondary alcohol moiety; - Having a well-defined and known stereochemistry. According to these terms, we propose three different potential linkers (see Figure 2) that can be incorporated into the solid-phase synthesis of ONs. Starting materials are commercially available as pure enantiomers at an affordable price. Here we report the synthesis and characterisation of an alkyne-bearing linker and the synthesis and radiosynthesis of the complementary azido-bearing prosthetic groups (1-(azidomethyl)-4-[18F]-fluorobenzene). [less ▲]

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See detail18F LABELING OF BIOMOLECULES USING CLICK CHEMISTRY FOR PET APPLICATIONS : SYNTHETIC DEVELOPMENTS
Thonon, David ULg; Flagothier, Jessica ULg; Paris, Jérôme ULg et al

in Drugs of the Future (2008, August), 33(A), 235

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See detailClick chemistry for 18F labelling of bioactive compounds
Paris, Jérôme ULg; Thonon, David ULg; kech, cecile et al

Poster (2008, July 03)

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See detailSynthesis of high-relaxivity contrast agents for magnetic resonance imaging by "click" chemistry
Vanasschen, Christian; Thonon, David ULg; Lecomte, Philippe ULg et al

Poster (2007, August 31)

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See detailSynthèse de chélateurs bifonctionnels en vue du développement d’agents de contraste pour l’IRM
Thonon, David ULg; Paris, Jérôme; Jacques, Vincent et al

Conference (2007)

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See detailA gadolinium triacetic monoamide DOTA derivative with a methanethiosulfonate anchor group. Relaxivity properties and conjugation with albumin and thiolated particles
Thonon, David ULg; Jacques, Vincent; Desreux, Jean-François ULg

in Contrast Media & Molecular Imaging (2007), 2

The gadolinium(III) complex with a new DOTA-based ligand bearing a methanethiosulfonate group (MTS) was synthesized and its relaxivity properties were investigated. MTS-ADO3A is a triacid DOTA derivative ... [more ▼]

The gadolinium(III) complex with a new DOTA-based ligand bearing a methanethiosulfonate group (MTS) was synthesized and its relaxivity properties were investigated. MTS-ADO3A is a triacid DOTA derivative with an amide arm substituted by an ethylmethanethiosulfonate function. This ligand was obtained in two steps: tri-tert-butyl 2,2′,2″-(1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetate was reacted with S-(2-aminoethyl)methanesulfonothioate and the tert-butyl groups were removed with trifluoroacetic acid. The Gd(III) MTS–ADO3A complex readily formed disulfide bonds with albumin (BSA) in its native and reduced forms and with thiolated silica particles. Four- to five-fold relaxivity increases at 20 MHz were measured on the isolated adducts. The EuMTS-ADO3A chelate was found to be monohydrated by fluorescence and the relaxivity parameters of the Gd(III) complex were obtained by 17O NMR and by measuring the nuclear magnetic relaxation dispersion between 0.01 and 80 MHz. The water exchange time τm is increased upon forming disulfide bonds with macromolecules and particles and the relaxivity gains of all the complexes are limited by the τm factor. Forming covalent or hydrophobic/electrostatic bonds with BSA seems to bring about similar relaxivity changes but the covalent BSA adducts can be isolated and their properties can be directly studied. The addition of dithiothreitol or glutathione leads to the removal of the metal chelates from the macromolecules, as indicated by the relaxation times reverting to their values before binding. It is thus expected that the chelate will stay in the body long enough for imaging but will still be excreted through the kidneys. [less ▲]

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See detailRoutes to increase the relaxivity of contrast agents for MRI
Thonon, David ULg; Vanasschen, Christian; Paris, Jérôme et al

Poster (2006)

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See detailSynthèse de ligands ditopiques en tant qu’agents de contraste pour l’imagerie de résonance magnétique.
Thonon, David ULg; Paris, Jérôme; Humblet, Jacques et al

Poster (2003)

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See detailLanthanide DOTA chelates bearing a methanethiosulfonate group as contrast agents for magnetic resonance imaging
Thonon, David ULg; Paris, Jérôme; Jacques, Vincent et al

Poster (2002)

Detailed reference viewed: 3 (1 ULg)