1H and 13C NMR spectra were recorded on a Bruker Avance III-500 or III-600 NMR spectrometer (chemical shifts with respect to (TMS) = 0 ppm). Solution electronic absorption and emission spectra were recorded on an Agilent 8453 spectrophotometer and Shimadzu 5301PC spectrofluorophotometer, respectively; a Perkin Elmer Spectrum Two UATR instrument was used to record FT-IR spectra of solid samples...

give them important clues about the current chemical environment of the moon (from surface samples) and about the presence of a lunar sea or ocean in the distant past (from core samples). Present-day commercial NMR spectrometers are capable of accomplishing, unaided, the work assigned to the JPL team with a creditable degree of success. But when you're analyzing samples that cost about a millio...

Natural products provide excellent potential leads for drug development because of their chemical diversity and biological functionality. However, the productivity of discovery of new, pharmacologically active natural products has traditionally been low due to inherent difficulties and costs associated with extract dereplication, i.e., isolation, purification and structure elucidation of indivi...

Ž . The dc Superconducting QUantum Interference Device SQUID is a sensitive detector of magnetic flux, with a typical flux noise of the order 1 mF Hz at liquid helium temperatures. Here F s"r2 e is the flux quantum. In our NMR or 0 0 NQR spectrometer, a niobium wire coil wrapped around the sample is coupled to a thin film superconducting coil deposited on the SQUID to form a flux transformer. W...

I. General methods All Fmoc-protected natural amino acids were purchased from Advanced Chemtech (Louisville, KY). Fmocperfluorophenylalanine (Fmoc-Z) was purchased from Chem-Impex Int’l Inc.(Wood Dale, IL). Fmoc-Gly-Wang resin was purchased from Novabiochem (San Diego, CA). All other chemicals were purchased from Sigma-Aldrich (Milwaukee, WI). Peptide synthesis was finished on a Tribute peptide...

This article contains NMR (nuclear magnetic resonance) experimental data, obtained by the NMR Varian 400 MHz spectrometer (USA) which can be used for the metabolites identification in human blood. Data include analyzed NMR spectra of plasma proteins extracted from human blood of 24 patients (0-5 years old) with the confirmed acute leukemia diagnosis. Data can provide information about metabolit...

H and C nuclear magnetic resonance (NMR) spectra were recorded at 400 MHz on a Bruker ARX-400 NMR spectrometer (Germany) with tetramethylsilane as internal standard. Column chromatography was performed using Merck (Germany) silica gel (230-400 mesh). Thin layer chromatography (TLC) was performed using Merck silica gel GF254, 0.25 mm thickness. For visualization, TLC plates were placed under aci...

A theory of nuclear magnetic resonance (NMR) in graphene is presented. The canonical form of the electron-nucleus hyperfine interaction is strongly modified by the linear electronic dispersion. The NMR shift and spin-lattice relaxation time are calculated as a function of temperature, chemical potential, and magnetic field, and three distinct regimes are identified: Fermi-, Dirac-gas, and extre...

background: sodium valproate (vpa), an anticonvalsant drug, has been reported to stimulate viral replication.  a combination therapy with vpa and acyclovir (acv) is used for the treatment of herpesvirus encephalitis, the commonest sporadic encephalitis of viral origin.   objective: to determine a possible interaction between vpa and acv leading to a modification of antiviral activity of acv.   ...

The (13)C NMR characterization of the 2,2'- and the 4,4'-hexaarylbiimidazoles is reported for the first time as resulting from the recombination of the radical pairs produced upon irradiation of the 1,2'-dimer, without any isolation processes, directly in a 500 MHz NMR spectrometer coupled with in situ laser irradiation.