Computer-aided structure elucidation methods

There are two kinds of computer-aided structure elucidation methods logic-oriented and database-oriented approaches. The computer program systems adopted for either approach require a high quality spectral database. The authors have been constructing proton and carbon-13 NMR spectral databases applicable to the computer systems for both approaches for more than 10 years. ... 

The previous sections dealt with many methods both for the interpretation and verification of LR MS. The results are still not sufficient for automated structure elucidation in many cases (although some successful examples will be described in Chapter 9), due in part to the lack of information available in a LR MS spectrum. Nevertheless, the methods introduced provide a framework for computer-aided structure elucidation, and they can serve as starting point for further research. 

See E. Pretsch. G. Toth. M. E. Monk, and M. Badertscher, Computer-Aided Structure Elucidation. Spectra Interpretation and Structure Generation, New York VCH-Wiley, 2003 B. C. Smith, Infrared Spectral Interpretation A Systematic Approach, Boca Raton. FL CRC Press. 1998. Chap. 9 W, 0. George and H. Willis. Computer Methods in UV, Visible and IR Spectroscopy, New York Springer-Verlag, 1990. 

Dubois et al. developed the Description, Acquisition, Retrieval, Computer-aided design-Elucidation by Progressive Intersection of Ordered Structures (DARC-EPIOS) system for structural elucidation.Their approach was based on C spectra. These were predicted using an additive method, but based on their DARC descriptor of environment, as opposed to the more common HOSE code. The EPIOS system was designed to take account of the diagnostic (or not) nature of the C spectrum with respect to environment, i.e., depending on the specific sub-structures. 

The purpose of a chemical expert system is to provide fast, easy, efficient and effective access to chemical information and knowledge in a specific domain of expertise, via computer-representation of integrated reference data, theoretical and empirical knowledge (e.g., in the form of rules ), system models and reasoning mechanisms. An expert system should not only contain (integrated) relevant hard facts (e.g., numerical correlations and statistics) but also the expertise ( soft knowledge ) of experienced specialists in the field. For structure elucidation of organic molecules various spectrometric methods are available. In many cases different methods such as mass, infra-red, NMR and ultra-violet spectroscopy provide complementary structural information. This is one of the basic elements of EXSPEC, an expert system for computer-aided interpretation of combined spectral data. ... 

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