Search results for "1H-NMR"
showing 5 items of 5 documents
Urinary metabolomics of bronchopulmonary dysplasia (BPD): preliminary data at birth suggest it is a congenital disease
2014
Abstract Objective: Bronchopulmonary dysplasia (BPD) or chronic lung disease is one of the principal causes of mortality and morbidity in preterm infants. Early identification of infants at the greater risk of developing BPD may allow a targeted approach for reducing disease severity and complications. The trigger cause of the disease comprehends the impairment of the alveolar development and the increased angiogenesis. Nevertheless, the molecular pathways characterizing the disease are still unclear. Therefore, the use of the metabolomics technique, due to the capability of identifying instantaneous metabolic perturbation, might help to recognize metabolic patterns associated with the cond…
The synthesis, structure and properties of N-acetylated derivatives of ethyl 3-amino-1H-pyrazole-4-carboxylate.
2007
Ethyl 3-amino-1H-pyrazole-4-carboxylate (1) was yielded through total synthesis and reacted with acetic anhydride to give the acetylated products 2-6. Compounds 1-6 were studied with HPLC, X-ray, FT-IR, (1)H-NMR, (13)C-NMR and MS. Acetylation was carried out in solvents of various polarity, namely; chloroform; dioxane; DMF; acetic anhydride, at room temperature and at boiling points; and in the presence and absence of DMAP. The acetylated products are mainly nitrogen atoms in the ring. The position of the ring proton in the solution was based on NOESY; multinuclear HMBC, HSQC spectra and calculations. For equivalent amounts (1-1.5 mol) of acetic anhydride at room temperature two products of…
Comparing different processing methods in apple slice drying. Part 2 solid-state Fast Field Cycling 1H-NMR relaxation properties, shrinkage and chang…
2019
The objective of this paper was to study the effects of different drying methods that are: microwave (MW), hot air (HA) and a combination of both (HY), on the 1H-NMR relaxation properties, shrinkage and volatile compounds of Golden Delicious apple slices. Fast field cycling NMR relaxometry reveals that the HA samples dried at different temperatures (65 and 75 °C) appear to contain less restrained water as compared to the sample obtained by MW heating at the same temperatures. In fact, the longitudinal relaxation rates (T1) of the water molecules in the HA dried slices resulted shorter than those measured for the MW dried samples, thereby revealing that in the MW slices, water molecules beha…
Synthesis, Characterization, and Saccharide Binding Studies of Bile Acid − Porphyrin Conjugates
2007
Synthesis and characterization of bile acid-porphyrin conjugates (BAPs) are reported. Binding of saccharides with BAPs in aqueous methanol was studied by monitoring changes in the visible absorption spectral of the porphyrin-moieties. Although these studies clearly showed absorbance changes, suggesting quite high if non-selective binding, the mass spectral studies do not unambiguously support these results.
1H NMR Spectroscopy with Multivariate Statistical Analysis as a Tool for a Rapid Screening of the Molecular Changes Occurring During Micro-Oxygenatio…
2008
A red wine from Aglianico vine was subjected to a micro-oxygenation procedure for five weeks. The wine was weekly sampled together with a non micro-oxygenated control and extracted with di-ethyl-ether in order to simplify NMR analyses. In fact, 1 H NMR spectra of the whole wine samples were dominated by water and ethanol signals which pre- vented visibility of the resonances generated by the less concentrated wine components. The 1 H NMR analyses of the di- ethyl-ether extracts revealed an increase of the amount of oxygen-containing materials. Such increase was attributed to a wine ageing process which resulted, hence, fastened by application of micro-oxygenation.