Concurrent combined verification: reducing false positives in automated NMR structure verification through the evaluation of multiple challenge control structures

Golotvin, S. S.; Pol, Rostislav; Sasaki, Ryan; Nikitina, A. F.; Keyes, Philip

doi:10.1002/mrc.3818

Cited by 10 publications

(6 citation statements)

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“…It relies on 13 C chemical shift assignments from 2D NMR data, optionally supported by chemical shift prediction. The result of a structure verification should be either yes or no at the end of the analysis, and thus the number of false positives (accepted wrong structures) and of false negatives (rejected correct structures) should be minimized …”

Section: Introductionmentioning

confidence: 99%

Structure verification through computer‐assisted spectral assignment of NMR spectra

Plainchont

Nuzillard

2012

Magnetic Reson in Chemistry

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The validation of a molecular organic structure on the basis of 1D and 2D HSQC, COSY and HMBC NMR spectra is proposed as an alternative to the methods that are mainly based on chemical shift prediction. The CCASA software was written for this purpose. It provides an updated and improved implementation of the preceding computer-assisted spectral assignment software. CCASA can be downloaded freely from http://www.univ-reims.fr/LSD/JmnSoft/CASA. Two bioactive natural products, a triterpene and a benzophenone, were selected from literature data as examples. The tentative matching between the structure and the NMR data interpretation of the triterpene unexpectedly leads to the hypothesis of an incorrect structure. The LSD software was used to find an alternative structure that improved the 2D NMR data interpretation and the carbon-13 chemical shift matching between experimental values and those produced by the nmrshiftdb2 prediction tool. The benzophenone example showed that signal assignment by means of chemical shift prediction can be replaced by elementary user-supplied chemical shift and multiplicity constraints.

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Section: Introductionmentioning

confidence: 99%

Structure verification through computer‐assisted spectral assignment of NMR spectra

Plainchont

Nuzillard

2012

Magnetic Reson in Chemistry

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“…[145] A procedure closely related to elucidation and dereplication is structure verification. This was usually considered an independent method, [146] but it recently began to be consolidated with CASE programs. The method of unbiased verification (UBV) was introduced, which constitutes the next step in verification.…”

Section: Case As a Tool For Structure Revision Dereplication And Verificationmentioning

confidence: 99%

Computer Assisted Structure Elucidation (CASE): Current and future perspectives

Elyashberg¹,

Argyropoulos²

2020

Magnetic Reson in Chemistry

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The first efforts for the development of methods for Computer-Assisted Structure Elucidation (CASE) were published more than 50 years ago. CASE expert systems based on one-dimensional (1D) and two-dimensional (2D) Nuclear Magnetic Resonance (NMR) data have matured considerably by now. The structures of a great number of complex natural products have been elucidated and/or revised using such programs. In this article, we discuss the most likely directions in which CASE will evolve. We act on the premise that a synergistic interaction exists between CASE, new NMR experiments, and methods of computational chemistry, which are continuously being improved. The new developments in NMR experiments (long-range correlation experiments, pure-shift methods, coupling constants measurement and prediction, residual dipolar couplings [RDCs]), and residual chemical shift anisotropies [RCSAs], evolution of density functional theory (DFT), and machine learning algorithms will have an influence on CASE systems and vice versa. This is true also for new techniques for chemical analysis (Atomic Force Microscopy [AFM], "crystalline sponge" X-ray analysis, and micro-Electron Diffraction [micro-ED]), which will be used in combination with expert systems. We foresee that CASE will be utilized widely and become a routine tool for NMR spectroscopists and analysts in academic and industrial laboratories. We believe that the "golden age" of CASE is still in the future.

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“…Typical datasets for the test cases thus included (a) the elemental composition derived from high-resolution MS data; (b) 1D 1 H and 13 C spectra; (c) 1 H, 13 C-HSQC and 1 H, 13 C-HMBC spectra; and (d) in some cases 1 H, 1 H-COSY or 1 H, 15 N-HMBC data. Typical datasets for the test cases thus included (a) the elemental composition derived from high-resolution MS data; (b) 1D 1 H and 13 C spectra; (c) 1 H, 13 C-HSQC and 1 H, 13 C-HMBC spectra; and (d) in some cases 1 H, 1 H-COSY or 1 H, 15 N-HMBC data.…”

Section: Examplesmentioning

confidence: 99%