13C solid-state NMR experiments were performed to investigate the structure of beeswax in the native state (crude beeswax) for the first time. From quantitative direct polarization 13C MAS NMR spectrum, it was found that the fraction of internal-chain methylene (int-(CH2)) component compared to other components of crude beeswax was over 95%. The line shape of the int-(CH2) carbon resonance regi...

Several anisotropic nuclear spin interactions in solid potassium tetracyanomercurate(II), K2Hg(CN)4, have been characterized using 13C, ISN, and Ig9Hg N M R spectroscopy at 4.70 and 9.40 T. The carbon chemical shielding tensor is axially symmetric, with anisotropy, Au = ull 61 = 329 f 2 ppm. From the 13C and Ig9Hg N M R spectra obtained with magic-angle spinning (MAS), 1J(199Hg,13C)i, = 1540 f ...

ABSTRACT Spin-lattice relaxation times, T1s, for 13C nuclei in two cations H n1n+ (n = 1, 5) of N-(2-aminoethyl)-cyclam (1, scorpiand) were determined by means of 13C{1H} NMR experiments in aqueous solution at pH 11.5 and 0.2. The theoretical study [modeling with OPLS-AA, B3LYP/6-31G(d) geometry optimizations, dispersion-corrected energies (DFT-D3), and DFT-GIAO predictions of the NMR chemical ...

Some of the Adamantane properties were calculated in this study. Chemical shift, free energy ofsolvation, free energy of cavity formation, Henry's law constant, and other properties ofAdamantane in dry phase, three solvents and three temperatures have been calculated with Abinitio method base on density functional theory (DFT) at B3lyp/6-31g, B31yp/6-31g*, B3lyp/6-31+g* and B3lyp/6-31++g** leve...

The glycosaminoglycan hyaluronan is a vital structural component of extracellular matrices with diverse biological functions, a molecular understanding of which requires a detailed description of secondary and tertiary solution structures. Various models of these structures have been proposed on the basis of 1H and 13C natural-abundance nuclear magnetic resonance (NMR) experiments, but resonanc...

The first NMR spectra of proteins, obtained in the 1950s and 1960s, focused on the 1H nucleus because of its spin I = 1/2 nature, high natural abundance, and sensitivity.1 – 6 However, because of the small range of chemical shifts (due to folding) and the low spectral resolution available on 60-, 100-, and even 220-MHz instruments, there was relatively little spectral resolution available, and ...

Upon alignment of oligonucleotides in a magnetic field, the downfield TROSY component of the 13C-{1H} doublet changes its resonance frequency as a result of residual 13C-1H dipolar coupling (RDC) and residual 13C chemical shift anisotropy (RCSA), and the sum of these two second rank tensors is referred to as the pseudo-CSA. The experimentally measured difference in the resonance frequency of th...

Angolamycin (1) and two novel analogues (2 and 3) were isolated from the culture broth of a Streptomyces strain. NMR and MS analysis proved that 2 is the 18-dihydro-, while 3 is the 18-deoxo-18-dihydro derivative of angolamycin. Full experimental assignment of the 1H and the 13C NMR spectra of these compounds was obtained from 1D and 2D chemical shift correlation measurements. Compounds 2 and 3...