Generated tautomeric forms for NCI structure dataset

All structures containing more than 60 heavy atoms and more than 4 rings were removed and the basic dataset size is 70 878. They were pre-processed using ChemAxon Standardizer version 5.12.2 including extraction of SMILES linear notation from sdf files, kekulization of aromatic structures, conversion of explicit hydrogen atoms to implicit ones and removal of stereo information. All tautomeric forms for the testing structures were generated by means of Ambit-Tautomer software [https://doi.org/10.1002/minf.201200133], IA-DFS algorithm (incremental approach based on depth-first search) with tautomeric rules for 1.3 and 1.5 hydrogen shifts and removal of topologically equivalent atoms and allene atom. All generated tautomeric forms for the dataset is 1 379 518.