Structure-Based Classification of Chemical Reactions without Assignment of Reaction Centers Qing-You Zhang João Aires-de-Sousa 10.1021/ci0502707.s001 https://acs.figshare.com/articles/journal_contribution/Structure_Based_Classification_of_Chemical_Reactions_without_Assignment_of_Reaction_Centers/3254545 The automatic classification of chemical reactions is of high importance for the analysis of reaction databases, reaction retrieval, reaction prediction, or synthesis planning. In this work, the classification of photochemical reactions was investigated with no explicit assignment of the reacting centers. Classifications were explored with Random Forests or Kohonen neural networks in three different situations, using different levels of information:  (a) pairs of reactants were classified according to the type of reaction they produce, (b) products were classified according to the type of reaction from which they can be synthesized, and (c) reactions were classified from the difference between the descriptors of the product and the descriptors of the reactants. In all cases molecular maps of atom-level properties (MOLMAPs) were used as descriptors. They are generated by a self-organizing map and encode physicochemical properties of the bonds available in a molecule. Correct classification could be achieved for approximately 90% of the 78 reactions in an independent test set. 2005-11-28 00:00:00 encode physicochemical properties synthesis planning 78 reactions Reaction Centers reaction prediction MOLMAP chemical reactions Random Forests reaction retrieval Chemical Reactions reaction databases Correct classification