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Structure-Function Elucidation of Flavonoids by Modern Technologies
Published in Dilip Ghosh, Pulok K. Mukherjee, Natural Medicines, 2019
Ritu Varshney, Neeladrisingha Das, Rutusmita Mishra, Partha Roy
Heteronuclear NMR experiments are mainly performed by heteronuclear single quantum coherence spectroscopy (HSQC). In this case, the resulting spectrum is a 2D spectrum having one axis designated for the proton (1H) and the other axis designated for other heteronucleus, which is usually 13C or 15N. 1H-13C-HSQC is generally conducted to deduce the structural aspects of most of the organic compounds. It mainly provides the correlation between the aliphatic carbon and the associated protons. The main advantage of this experiment is increased sensitivity (<1.0 mg flavonoid sample).
Polynuclear Platinum Drugs
Published in Astrid Sigel, Helmut Sigel, Metal Ions in Biological Systems, 2004
In parallel, the kinetics of formation and structure of (Pt,Pt) interstrand crosslinks have been investigated to place the results of the previous section on a firm structural basis. To evaluate the kinetics of binding in more detail, fully-15N labelled I and II were prepared and the reactions with defined oligonucleotides examined by {!H,15N} HSQC NMR spectroscopy. In this way, it is possible to observe all platinated species at low (μM) concentrations because only *H and 15N resonances derived from platinum am(m)ine species are seen and the 15N shifts are strongly influenced by the trans ligand [66]. These methods have provided new insight into the kinetics and mechanism of DNA binding by cisplatin and other mononuclear analogs [67,68]. {1H,15N} HSQC NMR is proving to be especially useful for following the reactions of polynuclear platinum complexes because 15N-labeling of both 15NH2 and 15NH3 groups is possible - allowing the local environment surrounding both ends of the molecule, as well as the central linker of BBR3464 at every stage of the process to be examined. Stepwise formation of long-range DNA interstrand cross-links and the kinetic parameters for each step in the pathway have been observed.
Mycobacterial surface characters remodeled by growth conditions drive different tumor-infiltrating cells and systemic IFN-γ/IL-17 release in bladder cancer treatment
Published in OncoImmunology, 2022
Sandra Guallar-Garrido, Víctor Campo-Pérez, Míriam Pérez-Trujillo, Cecilia Cabrera, Jordi Senserrich, Alejandro Sánchez-Chardi, Rosa Maria Rabanal, Elisabet Gómez-Mora, Estela Noguera-Ortega, Marina Luquin, Esther Julián
For the NMR analysis each purified compound was dissolved in 600 µL of CDCl3 (99.80% D, Cortecnet, Voisins-le-Bretonneux, France). A Bruker Avance II 600 NMR spectrometer (Bruker Biospin, Rheinstetten, Germany) equipped with a 5 mm TBI probe operating at a 1H and 13C NMR frequencies of 600.13 and 150.90 MHz, respectively, was used. All experiments were performed at 298.0 K. 1D 1H NMR spectra were acquired using a standard 90° pulse sequence, with an acquisition time of 1.71 s and a relaxation delay of 2 s. Data were collected into 32 K computer data points, with a spectral width of 9590 Hz and as the sum of 1024 transients. In the case of quantitative 1D 1H NMR spectrum the relaxation delay was set to 15s. 2D NMR experiments 1H,1H-COSY (Correlation Spectroscopy) and 1H,13C-HSQC (Heteronuclear Single Quantum Coherence) were performed using standard Bruker pulse sequences and acquired under routine conditions. All spectra were calibrated using the residual solvent signal (CHCl3,δH, 7.26 and δC, 77.0 ppm). Multiplicity of peaks is abbreviated as s (singlet), d (doublet), t (triplet), dd (doublet of doublets) and m (multiplet). Integration was performed with the global spectral deconvolution (GSD) application of MestreNova 8 (Mestrelab Research S.L.).
Exploring the metabolomic profile of cerebellum after exposure to acute stress
Published in Stress, 2021
Aikaterini Iliou, Angeliki-Maria Vlaikou, Markus Nussbaumer, Dimitra Benaki, Emmanuel Mikros, Evangelos Gikas, Michaela D. Filiou
The Chenomx NMR suite v.8.4. (Chenomx Inc., Alberta, Canada) was used for metabolite identification. 2 D NMR experiments (multiplicity-edited Heteronuclear Single Quantum Correlation-HSQC-DEPT and Total Correlation Spectroscopy (TOCSY)) in selected samples aided molecular identification. Statistical Total Correlation Spectroscopy (STOCSY), a mathematical technique for the identification of correlated spectral features, was also used to provide latent information for metabolite identification. Pathway enrichment analysis was performed by Over Representation Analysis (ORA). ORA was implemented in MetaboAnalyst 4.0 (https://www.metaboanalyst.ca/) (Chong et al., 2018) using the hypergeometric test and the pathway-associated metabolite sets from The Small Molecule Pathway Database (https://smpdb.ca).
Evaluation of the published kinase inhibitor set to identify multiple inhibitors of bacterial ATP-dependent mur ligases
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2019
Martina Hrast, Kaja Rožman, Iza Ogris, Veronika Škedelj, Delphine Patin, Matej Sova, Hélène Barreteau, Stanislav Gobec, Simona Golič Grdadolnik, Anamarija Zega
The heteronuclear single quantum coherence (HSQC) spectra for 1H/13C were acquired with 1024 data points in t2, 32 scans, 64 complex points in t1, and relaxation delay of 1 s. The 1H and 13C sweep widths were 9470 and 3338 Hz, respectively. The spectra were processed and analysed with the Felix 2007 software package (Felix NMR Inc., Laboratory of Biomolecular Structure at National Institute of Chemistry). The spectra were zero-filled twice and apodised with a squared sine bell function shifted by π/2 in both dimensions using a linear prediction of the data in the incremented dimension. The combined 1H/13C chemical shift perturbations (Δδ) were calculated from the 1H and 13C chemical shift perturbations using Equation (1)32: