Background: Juvenile Idiopathic Arthritis (JIA) is associated with joint inflammation, pain and limited joint mobility, impacting the practice of physical activities. Adapted Physical Activities (APA) are an increasingly used method of rehabilitation, but additional studies are needed to define the nature of the most appropriate physical activity for patients with JIA. The "ATHLETIQUE" project aims to evaluate the impact of a program integrating APA sessions with use of a pedometer watch, on disease activity in patients with JIA.
View Article and Find Full Text PDFEnantiopure () and () cyclic α,α-disubstituted amino acid derivatives displaying a δ-valerolactam side chain were prepared from a common isoxazolidine precursor. The ()-configured δ-valerolactam was converted into diastereoisomeric pseudopeptides to investigate its ability to induce secondary structures in peptidomimetics. Conformational studies of these pseudopeptides were carried out in the solid state (X-ray diffraction), in solution (NMR analyses), and (computer-aided conformational analysis), which demonstrated that such quaternary amino acids induce β-turn conformations stable enough to be retained in polar media (DMSO).
View Article and Find Full Text PDFThe synthesis of unprecedented branched pyrrolizidines and indolizidines was accomplished via nitrone chemistry. The required ketonitrone, a known intermediate usually obtained as a mixture of regioisomers, was prepared in a pure form from d-arabinose by a sequence of oximation/reduction/oxidation steps. Nucleophilic vinylation or allylation followed by ring-closing metathesis of the corresponding N-allylpyrrolidines furnished the targeted iminosugars, which proved potent and selective inhibitors of alpha-glucosidase from rice (GH31 family).
View Article and Find Full Text PDFRare C-7-substituted aziridinyl iminosugars can be synthesized through a short reaction sequence involving 1,3-cycloaddition of cyclic nitrones with alkynes and a Baldwin rearrangement of isoxazolines into bicyclic 2-acylaziridines. The method is efficient and completely diastereoselective, producing stable aziridinyl iminosugars in high yields.
View Article and Find Full Text PDFPolyhydroxylated quinolizidines bearing a hydroxymethyl group at the ring junction were synthesized from a readily available l-sorbose-derived ketonitrone. Evaluated as glycoside hydrolase inhibitors, these quinolizidines revealed to be potent and selective α-glucosidase inhibitors. Quinolizidine 9a is the first quinolizidine-scaffolded iminosugar exhibiting nanomolar inhibition of a glycoenzyme.
View Article and Find Full Text PDF