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...

from hexanic extract of aerial parts of peucedanum ruthenicum m. bieb (apiaceae) collected from mazandaran province of iran, four triterpenoids namely taraxasterol, y-taraxasterol, poriferasterol and b-sitosterol have been isolated by column chromatography, thin layer chromatography, and crystallization. their structures were elucidated by spectroscopic methods (uv, ir, ms, 1h and 13c-nmr).

Puerariae Flos, the flowers of Pueraria. lobata (WILLD.) OHWI, is an important oriental crude drug used to ameliorate crapulence. In the preceding paper,' we described two triterpenoidal glycosides of the sophoradiol glucuronides, along with the known six aromatic compounds, kakkalide, daidzin, genistin, rutin, robinin and nicotiflorin. This paper further deals with a tryptophan derivative, ten...

Recent applications of high-field NMR spectroscopy in biosynthesis will be discussed. The emphasis of the lecture will be on the use of 1H, 3H, '3C and '5N-NMR to focus on individual steps of biochemical processes in the formation of natural products and related enzyme-catalyzed events. In the first set of experiments, pulse labelling and invivo studies are used to uncover biosynthetic sequence...

In light of global reef decline new methods to accurately, cheaply, and quickly evaluate coral metabolic states are needed to assess reef health. Metabolomic profiling can describe the response of individuals to disturbance (i.e., shifts in environmental conditions) across biological models and is a powerful approach for characterizing and comparing coral metabolism. For the first time, we asse...

Bendamustine hydrochloride is an alkylating antitumor agent with a good efficacy in the treatment of chronic lymphocytic leukemia (CLL) and B-cell non-Hodgkin's lymphoma (B-NHL). Under the stressed conditions, two degradant impurities in bendamustine hydrochloride drug product were detected by high-performance liquid chromatography. These two degradant impurities were isolated from preparative ...

Compound 1: H NMR (500 MHz, DMSO-d6) δ 11.64 (s, 1H), 8.73 (s, 4H), 8.57 (d, J = 1.4 Hz, 1H), 8.16 (dd, J = 8.9, 1.4 Hz, 1H), 7.81 (d, J = 8.5 Hz, 2H), 7.64 (d, J = 8.5 Hz, 2H), 6.99 (d, J = 8.9 Hz, 1H), 4.08 (t, J = 7.0 Hz, 2H), 3.28 (m, 2H), 1.69 (quin, J = 7.0 Hz, 2H), 1.33 (m, 8H), 0.86 (t, J = 6.8 Hz, 3H). C NMR (125 MHz, DMSO-d6) δ 162.6 (2xC = 0), 162.3 (2xC = 0), 158.9, 155.1, 151.9, 14...

In isotropic solution, internuclear dipolar couplings average to zero as a result of rotational diffusion. By dissolving macromolecules in a dilute aqueous nematic discotic liquid-crystalline medium containing widely spaced magnetically oriented particles, a tunable degree of solute alignment with the magnetic field can be created while retaining the high resolution and sensitivity of the regul...

1H nuclear magnetic resonance (NMR) spectroscopy can be used noninvasively to detect the proximal histidyl N delta proton signals of deoxymyoglobin in the myocardium. However, the quantification of deoxymyoglobin is based on the assumption that the deoxymyoglobin signal detected is not contaminated by the deoxyhemoglobin signals contributed from the blood. The purpose of this study was to condu...

Reductive 13C-methylation of proteins has been used as an isotope labeling strategy to study protein structure, function, and dynamics by nuclear magnetic resonance (NMR) spectroscopy. However, assigning the resulting 13C-dimethylamine peaks in a 1H-13C NMR spectrum has proved to be difficult, but it is important to expand the scope of the method. The assignment strategy presented here utilizes...