The reaction was carried out in dry EtOH under an argon atmosphere and at room temperature. NMR spectrum was recorded with a Bruker Avance 300 spectrometer and all chemical shifts are reported relative to the solvent signal [CDCl3: 7.26 ppm ( H)]. The assignments of the NMR signals were carried out under using 2D-NMR experiments H-HCOSY. IR spectra were recorded with a Thermo Nicolet NEXUS FTIR...

High-field proton magic-angle sample-spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy is shown to yield high-resolution 'H spectra of smectic, nematic and hexagonal-I1 phase lipids, from which isotropic chemical shifts, order parameters and relaxation times (q, qp and T,) can be determined. Such experiments are possible because of the special form of the dipolar Hamiltonian in such ...

Two factors determining the isotropic motional averaging of NMR spectra obtained from lipids in model and biological membranes systems are particle tumbling and lateral diffusion. The influence of these motions (of which the magnitudes are detemined by the medium viscosity and temperature) on the 31P-NMR spectra arising from unilamellar dioleoyl phosphatidylcholine vesicles of a defined size ar...

a-Amino Acid Esters, Peptide Esters, Platinum(IV) Complexes, "N NMR Spectra, Pt NMR Spectra The platinum(IV) complexes PtX4L2 (X = Cl, Br; 2 X = oxalate; L = glyOEt, glyglyOEt, gly-cleuOEt; 2 L = metOEt) have been obtained by oxidative addition of halogenes to platinum(II) compounds PtX2L2A high field shift of <3N (—50 ppm) is observed for the coordinated amino acid ligand of various platinum c...

The data shown in this article are related to the subject of an article in Carbohydrate Polymers, entitled "Synthesis and characterization of chitosan alkyl urea" [1]. 1H NMR and 13C NMR spectra of chitosan n-octyl urea, chitosan n-dodecyl urea and chitosan cyclohexyl urea are displayed. The chemical shifts of proton and carbon of glucose skeleton in these chitosan derivatives are designated in...

A robust method was developed to cluster similar NMR spectra from partially purified extracts obtained from a range of marine sponges and a plant biota. The NMR data were acquired using microtiter plate NMR (VAST) in protonated solvents. A sample data set which contained several clusters was used to optimize the protocol. The evaluation of the robustness was performed using three different clus...

Cross-polarized magic-angle-spinning NMR (CPMAS-NMR) techniques are assumed to be only semi-quantitative in the assessment of carbon distribution in humic substances or natural organic matter, due to a number of interferences such as spinning side bands (SSB) in spectra, paramagnetic species in samples, and low or remote protonation of aromatic carbons. Fast rotor spin rates or direct polarizat...

The purpose of the present study was to establish an experimental method to study the effects of quercetin on the metabolism of the drug-resistant leukemia cell line K562/ADM using nuclear magnetic resonance (NMR) technology. Drug administration to the cells was performed according to proper experimental design and application. The cells were collected and inactivated by repeated freeze-thaw cy...

Nuclear magnetic resonance, conventionally detected in magnetic fields of several tesla, is a powerful analytical tool for the determination of molecular identity, structure and function. With the advent of prepolarization methods and detection schemes using atomic magnetometers or superconducting quantum interference devices, interest in NMR in fields comparable to the Earth’s magnetic field a...