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31.
Mihaela Gulea Isabelle Abrunhosa Jozef Drabowicz Guillaume Grach Matthieu Hamel Serge Masson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1267-1272
Abstract A new method to prepare enantioenriched sulfinates was developed to obtain optically active ortho-methylsulfinyl(phenylphosphonates). It consists of a diastereoselective oxidation of sulfenates to sulfinates. Additionally, preliminary results concerning the synthesis of ortho-phophonylated benzylic thiol derivatives via a new P═S to P═C [1,4]-rearrangement and a first synthetic application of these compounds are also described. 相似文献
32.
The reaction of chloroacetyl chloride and triethylamine with a chiral imine derived from the combination of methyl glyoxylate and protected L-threonine gave two optically active α-amino acid derivatives with a cis-substituted β-lactam skeleton in a 72:28 ratio. The major product is obtained in 59% yield by simple crystallisation. 相似文献
33.
Emily F. Evans Norman J. Lewis Isabelle Kapfer Gregor Macdonald Richard J. K. Taylor 《合成通讯》2013,43(11):1819-1825
A mild and efficient procedure is described for the removal of the tert-butoxycarbonyl (BOC) group using boron trifluoride etherate and molecular sieves in dichloromethane at room temperature. The scope of this procedure is explored for the deprotection of a variety of amines including amino acid derivatives. 相似文献
34.
35.
Lana G. Kaiser Ma?gorzata Marjańska Gerald B. Matson Isabelle Iltis Seth D. Bush Brian J. Soher Susanne Mueller Karl Young 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2010,202(2):259-266
Glutathione (GSH) is a powerful antioxidant found inside different kinds of cells, including those of the central nervous system. Detection of GSH in the human brain using 1H MR spectroscopy is hindered by low concentration and spectral overlap with other metabolites. Previous MRS methods focused mainly on the detection of the cysteine residue (GSH-Cys) via editing schemes. This study focuses on the detection of the glycine residue (GSH-Gly), which is overlapped by glutamate and glutamine (Glx) under physiological pH and temperature. The first goal of the study was to obtain the spectral parameters for characterization of the GSH-Gly signal under physiological conditions. The second goal was to investigate a new method of separating GSH-Gly from Glx in vivo. The characterization of the signal was carried out by utilization of numerical simulations as well as experiments over a wide range of magnetic fields (4.0–14 T). The proposed separation scheme utilizes J-difference editing to quantify the Glx contribution to separate it from the GSH-Gly signal. The presented method retains 100% of the GSH-Gly signal. The overall increase in signal to noise ratio of the targeted resonance is calculated to yield a significant SNR improvement compared to previously used methods that target GSH-Cys residue. This allows shorter acquisition times for in vivo human clinical studies. 相似文献
36.
One‐pot reactions to produce 2,2′:6′,2″‐terpyridine (tpy) under mild conditions are described under both solventless and solvent‐assisted conditions. Tpy can be obtained in 32% yield in a simple one‐pot reaction, which can readily be scaled‐up to give large quantities of tpy. These new approaches are superior to those previously described because of the fast and efficient synthesis and purification of tpy. 相似文献
37.
The synthesis of 3-methyl-7-[2-(dimethylaminoethyl)oximino]-5-arylcyclopenta [f] benzoxa-zolinones, potential ligands of the 5HT1D receptors is described through a 4 steps reaction strategy from 3-methyl-6-acetyl benzoxazolinone. 相似文献
38.
Dr. Ludovic Fournier Dr. Isabelle Aujard Dr. Thomas Le Saux Sylvie Maurin Sandra Beaupierre Prof. Dr. Jean‐Bernard Baudin Prof. Dr. Ludovic Jullien 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(51):17494-17507
The small and synthetically easily accessible coumarinylmethyl backbone has been modified to generate a family of photolabile protecting groups with redshifted absorption. We relied on introducing electron‐donating groups in the 7 position and electron‐withdrawing groups in the 2‐, and 2‐ and 3 positions. In particular, we showed that the diethylamino‐thiocoumarylmethyl and the diethylamino‐coumarylidenemalononitrilemethyl are relevant for uncaging with cyan light. They both exhibit a significant action cross section for uncaging in the 470–500 nm wavelength range and a low light absorption between 350 and 400 nm. These attractive features are favorable to perform chromatic orthogonal photoactivation with UV and blue‐cyan light sources, respectively. 相似文献
39.
Vitor A. Kerber Carolina S. Passos Luiz C. Klein-Júnior Jean-Charles Quirion Xavier Pannecoucke Isabelle Salliot-Maire Amélia T. Henriques 《Tetrahedron letters》2014
Three new psychollatine-derived monoterpene indole alkaloids were obtained from Psychotria umbellata Thonn.: 3,4-Dehydro-18,19-β-epoxy-psychollatine (2), N4-[1-((R)-2-hydroxypropyl)]-psychollatine (3), and N4-[1-((S)-2-hydroxypropyl)]-psychollatine (4). Their structures were determined by 1H and 13C NMR spectra, 2D correlations (COSY, HMQC, and HMBC), and mass and UV spectra. Compounds 3 and 4 were synthesized for structural confirmation and for the determination of the stereochemistry of the hydroxyl group. 相似文献
40.
Sandy Theysgeur Benoit Cudennec Barbara Deracinois Claire Perrin Isabelle Guiller Anne Lepoudre Christophe Flahaut Rozenn Ravallec 《Molecules (Basel, Switzerland)》2021,26(1)
Like their owners, dogs and cats are more and more affected by overweight and obesity-related problems and interest in functional pet foods is growing sharply. Through numerous studies, fish protein hydrolysates have proved their worth to prevent and manage obesity-related comorbidities like diabetes. In this work, a human in vitro static simulated gastrointestinal digestion model was adapted to the dog which allowed us to demonstrate the promising effects of a tilapia byproduct hydrolysate on the regulation of food intake and glucose metabolism. Promising effects on intestinal hormones secretion and dipeptidyl peptidase IV (DPP-IV) inhibitory activity were evidenced. We identify new bioactive peptides able to stimulate cholecystokinin (CCK) and glucagon-like peptide 1 (GLP-1) secretions, and to inhibit the DPP-IV activity after a transport study through a Caco-2 cell monolayer. 相似文献