Structural revisions of natural products by Computer-Assisted Structure Elucidation (CASE) systems.

  title={Structural revisions of natural products by Computer-Assisted Structure Elucidation (CASE) systems.},
  author={Mikhail E. Elyashberg and Antony J. Williams and Kirill A. Blinov},
  journal={Natural product reports},
  volume={27 9},
Covering: up to the end of 2009 It is shown in this review that the application of an expert system for the purpose of computer-assisted structure elucidation allows the researcher to avoid the production of incorrect structural hypotheses, and also to evaluate the reliability of suggested structures. Many examples of structure revision using CASE methods are given. 

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The role of computer-assisted structure elucidation (CASE) programs in the structure elucidation of complex natural products.

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Computationally-assisted discovery and structure elucidation of natural products

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Recent developments in automated structure elucidation of natural products.

Advancements in the field of Computer-Assisted Structure Elucidation of Natural Products achieved in the past five years are discussed and the option to validate the result by an independent procedure, a high quality ab initio quantum mechanical calculation, is discussed.

Applications of a HOUDINI-Based Structure Elucidation System

A comparison of the performance of COCOA-based and HOUDINI-based SESAMI using a set of complex, naturally occurring compounds as a test set of unknowns revealed faster execution times and more efficient processing of ambiguous structural information for the latter.

Application of a new expert system for the structure elucidation of natural products from their 1D and 2D NMR data.

Applications of the latest version of the StrucEluc expert software system, enhanced to use 2D NMR data, to the structure elucidation of 60 recently isolated natural products illustrate that Struc eluc is a powerful and versatile analytical tool for the structure elaboration of natural products.

Applying computer-assisted structure elucidation algorithms for the purpose of structure validation: revisiting the NMR assignments of hexacyclinol.

The application of the ACD/Structure Elucidator expert system is described to help resolve the conflict between two different hypothetical hexacyclinol structures derived by different researchers from the NMR spectra of this complex natural product.

Computer‐assisted structure elucidation of natural products with limited 2D NMR data: application of the StrucEluc system

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The role of 2D NMR spectroscopy in CASE is discussed and the methods a natural product chemist may apply to elucidate the structure of a complex natural product are highlighted.

Structure Elucidator: A Versatile Expert System for Molecular Structure Elucidation from 1D and 2D NMR Data and Molecular Fragments

The use of fragments has frequently transformed very difficult 2D NMR elucidation challenges into easily solvable tasks and a strategy to utilize molecular fragments has been developed and optimized based on specific challenging examples.

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The rationale and implementation of the newly developed CASE system, CISOC-SES (Computerized Information System for Organic Chemistry-Structure Elucidation System), 2D NMR correlation information, instead of chemical shifts, is fully exploited through some novel approaches.

Are Deterministic Expert Systems for Computer-Assisted Structure Elucidation Obsolete?

The conclusion is that 2D NMR deterministic expert systems are certainly capable of elucidating large structures and can deal with the complexities associated with both poor and contradictory spectral data.