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Unequivocal determination of complex molecular structures using anisotropic NMR measurements.

ABSTRACT: Assignment of complex molecular structures from nuclear magnetic resonance (NMR) data can be prone to interpretational mistakes. Residual dipolar couplings and residual chemical shift anisotropy provide a spatial view of the relative orientations between bonds and chemical shielding tensors, respectively, regardless of separation. Consequently, these data constitute a reliable reporter of global structural validity. Anisotropic NMR parameters can be used to evaluate investigators' structure proposals or structures generated by computer-assisted structure elucidation. Application of the method to several complex structure assignment problems shows promising results that signal a potential paradigm shift from conventional NMR data interpretation, which may be of particular utility for compounds not amenable to x-ray crystallography.

SUBMITTER: Liu Y

PROVIDER: S-EPMC6596297 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Unequivocal determination of complex molecular structures using anisotropic NMR measurements.

Liu Yizhou Y Saurí Josep J Mevers Emily E Peczuh Mark W MW Hiemstra Henk H Clardy Jon J Martin Gary E GE Williamson R Thomas RT

Science (New York, N.Y.) 20170401 6333

Assignment of complex molecular structures from nuclear magnetic resonance (NMR) data can be prone to interpretational mistakes. Residual dipolar couplings and residual chemical shift anisotropy provide a spatial view of the relative orientations between bonds and chemical shielding tensors, respectively, regardless of separation. Consequently, these data constitute a reliable reporter of global structural validity. Anisotropic NMR parameters can be used to evaluate investigators' structure prop ...[more]

PMID: 28385960

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