Automatic Translation of GENSAL Representations of Markush Structures into Gremas Fragment Codes at IDC

Abstract

The IDC file of generic chemical structures and reactions in patents is based on the GREMAS search system. GREMAS allows very rapid search of structures, substructures and other information in this large database. Until now, the GREMAS fragment codes of generic chemical structures had to be derived manually. Using the formal language GENSAL for the description and graphical input of generic chemical structures, we are able to process them by a computer program. In addition to the research work on generic chemical structures by Professor Lynch’s team in Sheffield, we have developed a method of translating the GENSAL expressions into GREMAS fragments automatically. So we can use the well established GREMAS search software and the GENSAL input is compatible with the large and valuable IDC file. In this paper, the way of processing Markush structures at IDC using GENSAL is outlined. The generation of GREMAS fragments from an extended connection table representation using graph reduction methods is described.