New NOAH modules for structure elucidation at natural isotopic abundance
Ēriks Kupče1, Tim D W Claridge2
1Bruker UK Limited, Banner Lane, Coventry CV4 9GH, UK.
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|August 18, 2019
Summary
New NOAH modules enhance Nuclear Magnetic Resonance (NMR) supersequences for efficient small molecule structure elucidation. Double isotope filters (ZZ-filters) improve flexibility, enabling novel combinations for advanced NMR experiments and computer-assisted structure elucidation (CASE).
Area of Science:
- Analytical Chemistry
- Organic Chemistry
- Spectroscopy
Background:
- Nuclear Magnetic Resonance (NMR) spectroscopy is crucial for determining the structure of small organic molecules.
- Existing NMR supersequences can be limited in flexibility and the types of experiments they can integrate.
- Optimizing NMR experiments for efficiency and information content remains an active area of research.
Purpose of the Study:
- To introduce novel NOAH modules for NMR supersequences to enable structure elucidation from a single measurement.
- To enhance the flexibility and applicability of NMR supersequences through new module designs and combinations.
- To demonstrate the utility of these new supersequences in computer-assisted structure elucidation (CASE).
Main Methods:
- Development of new NOAH modules for NMR supersequences.
- Implementation of double isotope filters (ZZ-filters) to increase module permutation flexibility, utilizing 15N and 13C nuclides.
- Integration of time-shared experiments (2BOB) and multiple receiver experiments (PANSY-COSY) into NMR supersequences.
- Application of the new NOAH supersequences in a CASE study using CMCse software.
Main Results:
- Introduction of new NOAH modules that allow structure elucidation of small organic molecules from a single NMR measurement.
- ZZ-filters demonstrated to increase flexibility in module permutation, optimizing combinations of 15N and 13C experiments.
- Successful integration of incompatible parallel experiments (NOAH-2 BO) and multiple receiver experiments (NOAH-2 SC2) into NMR supersequences.
- Validation of the new NOAH supersequences in a CASE study, showcasing their effectiveness.
Conclusions:
- The new NOAH modules significantly advance NMR supersequence design, offering greater flexibility and enabling more information-rich experiments.
- These advancements facilitate efficient structure elucidation of small organic molecules using fewer measurements.
- The developed NOAH supersequences provide new avenues for designing powerful NMR experiments and enhance CASE capabilities.
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