James B. Mcalpine

# Posters/

Dissemination of original NMR data enhances the reproducibility of natural product research

The acquisition of 1D 1H NMR (HNMR) spectra is one of earliest steps in characterizing natural products and other organic molecules. For publication, HNMR information usually is “converted” into a table format, and sometimes spectral plots are provided. However, this transformation is lossy and frequently insufficient for unambiguous dereplication. This ambiguity can even lead to structural revision, such as in the recent case of aquatolide (1), a sesquiterpene lactone from Asteriscus aquaticus.

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# Publications/

OpenAccess Essential Parameters for Structural Analysis and Dereplication by 1H NMR Spectroscopy

Journal: Journal of Natural Products (RoMEO status: White) Published on
Categories: publications
Subjects: Pharmacognosy Phytochemistry NMR Spin simulation

The present study demonstrates the importance of adequate precision when reporting the δ and J parameters of frequency domain 1H NMR (HNMR) data. Using a variety of structural classes (terpenoids, phenolics, alkaloids) from different taxa (plants, cyanobacteria), this study develops rationales that explain the importance of enhanced precision in NMR spectroscopic analysis and rationalizes the need for reporting Δδ and ΔJ values at the 0.1–1 ppb and 10 mHz level, respectively.

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