RÉSUMÉ
Nuclear Magnetic Resonance (NMR) is an analytical technique extensively used in almost every chemical laboratory for structural identification. This technique provides statistically equivalent signals in spite of using spectrometer with different hardware features and is successfully used for the traceability and quantification of analytes in food samples. Nevertheless, to date only a few internationally agreed guidelines have been reported on the use of NMR for quantitative analysis. The main goal of the present study is to provide a methodological pipeline to assess the reproducibility of NMR data produced for a given matrix by spectrometers from different manufacturers, with different magnetic field strengths, age and hardware configurations. The results have been analyzed through a sequence of chemometric tests to generate a community-built calibration system which was used to verify the performance of the spectrometers and the reproducibility of the predicted sample concentrations.
Sujet(s)
Jus de fruits et de légumes/analyse , Vitis/composition chimique , Calibrage , Spectroscopie par résonance magnétiqueRÉSUMÉ
O-acetylserine sulfhydrylase (OASS), the enzyme catalysing the last step of cysteine biosynthesis in bacteria, is involved in antibiotic resistance and biofilm formation. Since mammals lack OASS, it is a potential target for antimicrobials. However, a limited number of inhibitors has been developed and crystallized in complex with OASS. STD-NMR was applied to study the interaction of the inhibitory pentapeptide MNYDI with the CysK and CysM OASS isozymes from Salmonella Typhimurium. Results are in excellent agreement with docking and SAR studies and confirm the important role played by the C-terminal Ile5 and the arylic moiety at P3 in dictating affinity.
Sujet(s)
Antibactériens/pharmacologie , Protéines bactériennes/antagonistes et inhibiteurs , O-acetylserine(thiol)-lyase/antagonistes et inhibiteurs , Antienzymes/pharmacologie , Modèles moléculaires , Oligopeptides/pharmacologie , Salmonella typhimurium/enzymologie , Antibactériens/composition chimique , Antibactériens/métabolisme , Peptides antimicrobiens cationiques/composition chimique , Peptides antimicrobiens cationiques/métabolisme , Peptides antimicrobiens cationiques/pharmacologie , Protéines bactériennes/composition chimique , Protéines bactériennes/génétique , Protéines bactériennes/métabolisme , Sites de fixation , O-acetylserine(thiol)-lyase/composition chimique , O-acetylserine(thiol)-lyase/génétique , O-acetylserine(thiol)-lyase/métabolisme , Antienzymes/composition chimique , Antienzymes/métabolisme , Cartographie épitopique , Haemophilus influenzae/enzymologie , Liaison hydrogène , Isoenzymes/antagonistes et inhibiteurs , Isoenzymes/composition chimique , Isoenzymes/génétique , Isoenzymes/métabolisme , Simulation de docking moléculaire , Résonance magnétique nucléaire biomoléculaire , Oligopeptides/composition chimique , Oligopeptides/métabolisme , Banque de peptides , Conformation des protéines , Motifs et domaines d'intéraction protéique , Protéines recombinantes/composition chimique , Protéines recombinantes/métabolisme , Similitude structurale de protéinesRÉSUMÉ
An interlaboratory comparison (ILC) was organized with the aim to set up quality control indicators suitable for multicomponent quantitative analysis by nuclear magnetic resonance (NMR) spectroscopy. A total of 36 NMR data sets (corresponding to 1260 NMR spectra) were produced by 30 participants using 34 NMR spectrometers. The calibration line method was chosen for the quantification of a five-component model mixture. Results show that quantitative NMR is a robust quantification tool and that 26 out of 36 data sets resulted in statistically equivalent calibration lines for all considered NMR signals. The performance of each laboratory was assessed by means of a new performance index (named Qp-score) which is related to the difference between the experimental and the consensus values of the slope of the calibration lines. Laboratories endowed with a Qp-score falling within the suitable acceptability range are qualified to produce NMR spectra that can be considered statistically equivalent in terms of relative intensities of the signals. In addition, the specific response of nuclei to the experimental excitation/relaxation conditions was addressed by means of the parameter named NR. NR is related to the difference between the theoretical and the consensus slopes of the calibration lines and is specific for each signal produced by a well-defined set of acquisition parameters.
RÉSUMÉ
The discovery of new highly potent and selective triple reuptake inhibitors is reported. The new classes of 1-(aryl)-6-[alkoxyalkyl]-3-azabicyclo[3.1.0]hexanes and 6-(aryl)-6-[alkoxyalkyl]-3-azabicyclo[3.1.0]hexanes are described together with detailed SAR. Appropriate decoration of the scaffolds was achieved with the help of a triple reuptake inhibitor pharmacophore model detailed here. Selected derivatives showed good oral bioavailability (>30%) and brain penetration (B/B > 4) in rats associated with high in vitro potency and selectivity at SERT, NET, and DAT. Among these compounds, microdialysis and in vivo experiments confirm that derivative 15 has an appropriate developability profile to be considered for further progression.
Sujet(s)
Composés azabicycliques/pharmacologie , Transporteurs de la dopamine/antagonistes et inhibiteurs , Transporteurs de la norépinéphrine/antagonistes et inhibiteurs , Transporteurs de la sérotonine/métabolisme , Animaux , Composés azabicycliques/composition chimique , Composés azabicycliques/pharmacocinétique , Fixation compétitive , Monoamines biogènes/métabolisme , Biodisponibilité , Transport biologique/effets des médicaments et des substances chimiques , Lignée cellulaire , Chromatographie en phase liquide à haute performance , Inhibiteurs des enzymes du cytochrome P-450 , Cytochrome P-450 enzyme system/métabolisme , Transporteurs de la dopamine/métabolisme , Humains , Mâle , Souris , Microdialyse , Microsomes du foie/métabolisme , Modèles chimiques , Structure moléculaire , Activité motrice/effets des médicaments et des substances chimiques , Transporteurs de la norépinéphrine/métabolisme , Cortex préfrontal/métabolisme , Rats , Relation structure-activitéRÉSUMÉ
Within the continuous quest for the discovery of novel compounds able to treat anxiety and depression, the generation of a pharmacophore model for 5-HT2C receptor antagonists and the discovery of a new class of potent and selective 5-HT2C molecules are reported.
Sujet(s)
Pyrroles/synthèse chimique , Pyrroles/pharmacologie , Pyrrolidones/synthèse chimique , Pyrrolidones/pharmacologie , Antagonistes des récepteurs 5-HT2 de la sérotonine , Antisérotonines/synthèse chimique , Antisérotonines/pharmacologie , Modèles moléculairesRÉSUMÉ
Following the recent disclosure of 3-methyl pyrrole-2,4-dicarboxylic acid 2-propyl ester 4-(1,2,2-trimethyl-propyl) ester, a potent and selective mGluR1 non-competitive antagonist, we report here a detailed exploration of the C-2 position of this scaffold with the preparation of differently substituted amides. Great improvement of the pharmacokinetic properties has been achieved through this exercise.