Development of Topological Fragment Spectra (TFS) Peak Identification System

Abstract

We have developed a peak identification system for topological fragment spectra (TFS). The TFS is a kind of quantitative representation of a chemical structure, which is based on enumeration and numerical characterization of all the possible substructures from a chemical structure. It is possible to obtain some variants of the TFS when different weighting methods are applied to the characterization of structural fragments generated. The purpose of the present system is in pursuing the meaning of each peak of TFS and to identify the substructures behind the peaks. The user can identify any peak by specify the peak of TFS on the screen interactively. Then the substructural fragments corresponded to the peak can be displayed with the basic peak information. Moreover, this system can be applied not only for a single structure but also the database that involves a large number of chemical structures. For the latter case, a synthetic spectrum obtained by two or more structures can be generated, and it is possible to identify any peak selected for them. The function of browsing the chemical structures of the database was also implemented for the user who wants to know what chemical structures were included in the database. The function allows the user to know the structures originated for generating the synthetic peak(s). The detail of the system will be described with a couple of illustrative examples.