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Correlation Between Experimental and DFT/GIAO Computed 13C NMR Chemical Shifts. A Theoretical Study on Pentacyclic Terpenoids (fernenes)
(Elsevier Science, 2010-08)
The 13C chemical shifts of 15 pentacyclic terpenoids (fernenes) are compared to predicted 13C NMR chemical shifts obtained via empirically scaled GIAO shieldings. We report that accurate (rms error approx. 1.5 ppm) predictions ...
Mapping of protein structural ensembles by chemical shifts
(Springer NetherlandsDordrecht, 2010-10)
Applying the chemical shift prediction programs SHIFTX and SHIFTS to a data base of protein structures with known chemical shifts we show that the averaged chemical shifts predicted from the structural ensembles explain ...
Unique magnetic shielding and bonding in Pnicogen nortricyclane Zintl clusters
(Elsevier B.V., 2020)
Configuration of stilbene derivatives by (1)H NMR and theoretical calculation of chemical shifts
(ELSEVIER SCIENCE BV, 2010)
The direct E/Z configuration assignment of tri- and tetra-substituted stilbenes (and other analogous olefins) when only one of the isomers is available is a quite challenging task. Sometimes, a chemical transformation or ...
Effects of side-chain orientation on the 13C chemical shifts of antiparallel β-sheet model peptides
(Springer, 2007-02)
The dependence of the 13C chemical shift on side-chain orientation was investigated at the density functional level for a two-strand antiparallel β-sheet model peptide represented by the amino acid sequence Ac-(Ala)3-X-(Ala)12- ...
Sequential nearest-neighbor effects on computed 13Cα chemical shifts
(Springer, 2010-09)
To evaluate sequential nearest-neighbor effects on quantum-chemical calculations of 13Cα chemical shifts, we selected the structure of the nucleic acid binding (NAB) protein from the SARS coronavirus determined by NMR in ...
A theoretical and experimental study to unequivocal structural assignment of tetrahydroquinoline derivatives
(2013-06-24)
The tetrahydroquinoline derivatives can be easily synthesized through Povarov reaction and have several important biological activities. This work describes a comparative study for the unequivocal assignment of molecular ...
The role of explicit solvent molecules in the calculation of NMR chemical shifts of glycine in water
(Springer, 2018-06)
We present the results of a computational study of the NMR properties of glycine in water solution at the level of density functional theory employing the B3LYP functional and the 6-31G(d,p) and pcSseg-2 basis sets, ...
Chemometric modeling of core-electron binding energies
(Springer/plenum PublishersNew YorkEUA, 2006)