COMPUTER-AIDED INTERPRETATION OF MASS-SPECTRA USING DATABASES WITH SPECTRA AND STRUCTURES .1. STRUCTURE SEARCHES

For databases containing spectra and structures of the reference compounds, structural descriptors ('fragments') have been derived that are used for structure searches in the databases. The 190 fragments have been defined according to the contents of the Wiley/NBS Mass Spectral Database and to fragmentation behaviour. A search for structures with defined fragments (absence or presence of certain fragments) retrieves certain classes of compounds. An application for checking a reference spectrum is discussed. A search for structures similar to a target structure has been developed to be used in cases where a structure can be proposed for the unknown compound. The most closely related structures existing in the database will be selected, the respective spectra often being the key for interpretation or structure elucidation, as illustrated by an example.