The supply of information on chemical reactions in the IDC system

Supply of information on chemical reactions. An advanced, topology-based method

“…Work with AI numbers has been carried out on a large scale with the GREMAS system for reaction documentation for 26 years. 3 It has hitherto been restricted, however, to carbon atoms that participate in the reaction. Experience with tens of thousands of searches has shown that for large files that are very actively searched it is essential to be able to recognize corresponding atoms and not to be forced to specify assumed intermediate steps while searching or even to exclude the possibility of any intermediate steps between the educt and product structures in question.…”

Status and future developments of reaction databases and online retrieval systems

“…The first two steps could be replaced by a dictionary search, especially in the case of inorganic compounds, but the overall strategy is the same. There are basically two aspects which can be searched in the CA/REGISTRY system: (1) preparation of substances and (2) reactions from A to B. The first step of a reaction search in the CA/REGISTRY system is a search for the chemical substances involved in the reaction.…”

“…46 It is even possible to specify the number of steps or the maximum/ minimum number which should be accepted in a reaction search. However, there are two limitations to this approach: (1) the reactions can only be searched based on the structures of the participating compounds and (2) all steps of the search reaction must occur in the same document, i.e., in a single literature reference. It is not possible to search for multistep chemical reactions where the different parts are recorded in different literature references.…”