SYSTEMATIC SEARCH FOR NEW TYPES OF CHEMICAL INTERCONVERSIONS - MATHEMATICAL-MODELS AND SOME APPLICATIONS

According to Formal-Logical Approach to Organic Reactions, the systema tical search for new, unprecedented types of chemical interconversions needs the complete sets of symbolic, reaction, structural, and skelet al equations to be generated. In this paper, the generation problems a re shown to be reduced to graph labeling problems and, more precisely, to constructive enumeration problems for orbit representatives of ind uced permutation groups acting on certain sets of vertex or edge label ings of well-defined graphs. The suggested combinatorial models make i t possible to take into account formal charges and unshared electrons (needed to describe ionic, radical, and oxidation-reduction processes) and unchanged bonds forming cycles (included in cyclic structures of educts and products and needed to describe, e.g., degenerate rearrange ments). The basic ideas of the effective generating algorithms, some r esults of the corresponding analytical enumeration techniques, and sev eral new reaction types found by computer programs are also discussed.