I have updated the page list open source cheminformatics toolkits. To date it includes:- OpenBabel (http://openbabel.org/wiki/Main_Page) RDKit (http://www.rdkit.org) CDK (https://cdk.github.io) Indigo (http://lifescience.opensource.epam.com/indigo/) OpenChemLib (https://github.com/Actelion/openchemlib/) ChemDoodle