Tautobase: An Open Tautomer Database

There has been decades of research on determining and predicting acid dissociation constants (p K a ) and the tautomer ratios both experimentally and theoretically. However, the lack of an extensive publicly available database of measured tautomeric ratios in water and nonaqueous solvents poses a challenge for the researchers interested in theoretical studies related to tautomers. Hereby, we present Tautobase, to date and to the best of our knowledge, the first extensive open-source tautomer database of measured and estimated tautomer ratios mainly in water, containing 1680 unique tautomer pairs.