ChemInform Abstract: Enzymatic Syntheses of Chiral sec-Alcohols and Their NMR Chemical Shifts Induced by a Chiral Lanthanide Shift Reagent.

This study investigates the application of the paramagnetic shift reagent tris(dipivaloylmethanato)-europium(III) in NMR spectral studies of permethoxyacridone alkaloids (1–3) and pyranoacridone alkaloids (4–6). The induced chemical shifts (∆δ) of all protons were observed for the same molecule, and were compared to deduce the positions resulting from the distance nearby the Eu(dpm)3. Assignment of the H-2, H-4 and H-8 of polysubstituted acridones could be distinguished based on the least-squares method of lanthanide-induced shifts plotted against the mole ratios of Eu(dpm)3 to the substrate. The developed method is not only potentially useful for determining the planar structures of polysubstituted compounds, such as acridones, anthraquinones, xanthones, flavonoids, and phenanthrenes, but also applicable for their stereochemistry.

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The 1H NMR spectra and the conformation of 1,6-anhydro-β-D-hexopyranoses and their triacetates

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19791949 ◽

1979 ◽

Vol 44 (6) ◽

pp. 1949-1964 ◽

Cited By ~ 28

Author(s):

Miloš Buděšínský ◽

Tomáš Trnka ◽

Miloslav Černý

Keyword(s):

Nmr Spectra ◽

Chemical Shifts ◽

Shift Reagent ◽

Point Of View ◽

Coupling Constants ◽

Lanthanide Shift Reagent ◽

Pyranose Ring ◽

H Nmr ◽

Vicinal Coupling Constants

The 1H NMR spectra of 1,6-anhydro-β-D-hexopyranoses and their triacetates, measured in hexadeuteriodimethyl sulfoxide or deuteriochloroform, confirmed the existence of these compounds in 1C4(D) conformations, with the pyranose ring partly planarized in dependence on the configuration of the substituents in positions C(2), C(3) and C(4). The effects of the substituents on the chemical shifts and the adjusted relationship for the dependence of vicinal coupling constants on the torsion angle are discussed in detail from the point of view of the determination of the configuration and the conformation of 1,6-anhydro-β-D-hexopyranoses and their derivatives. The 1H NMR spectra of triacetates were also measured in the presence of the lanthanide shift reagent, tris(1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedione) europium (III) [Eu.(FOD)3].

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Relativistic and Dynamic effects are needed to correctly model the 1H NMR Chemical Shifts of an Iridium Polyhydride Cluster

10.26226/morressier.5f6c5f439b74b699bf390ad2 ◽

2020 ◽

Author(s):

Abril C. Castro ◽

David Balcells ◽

Michal Repisky ◽

Trygve Helgaker ◽

Michele Cascella

Keyword(s):

1H Nmr ◽

Chemical Shifts ◽

Dynamic Effects ◽

Nmr Chemical Shifts

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Faculty Opinions recommendation of Protein structure determination from NMR chemical shifts.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1091126.544522 ◽

2007 ◽

Author(s):

Thomas Szyperski

Keyword(s):

Protein Structure ◽

Structure Determination ◽

Chemical Shifts ◽

Protein Structure Determination ◽

Nmr Chemical Shifts

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Accurate prediction of 195Pt NMR chemical shifts for a series of Pt(ii) and Pt(iv) antitumor agents by a non-relativistic DFT computational protocol

Dalton Transactions ◽

10.1039/c3dt53594k ◽

2014 ◽

Vol 43 (14) ◽

pp. 5409-5426 ◽

Cited By ~ 27

Author(s):

Athanassios C. Tsipis ◽

Ioannis N. Karapetsas

Keyword(s):

Dft Calculations ◽

Anticancer Agents ◽

Antitumor Agents ◽

Chemical Shifts ◽

Accurate Prediction ◽

Nmr Chemical Shifts ◽

Relativistic Dft ◽

Square Planar ◽

Wide Range ◽

Computational Protocol

Exhaustive benchmark DFT calculations reveal that the non-relativistic GIAO-PBE0/SARC-ZORA(Pt)∪6-31+G(d)(E) computational protocol predicts accurate 195Pt NMR chemical shifts for a wide range of square planar Pt(ii) and octahedral Pt(iv) anticancer agents.

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