Information in Table summarizes relevant data in the analysis of NAPROC-13 and reference data sets studied in the present work. The number of exclusive entries refers to the number of compounds that do not share among the other databases. The SSE refers to the entropy of the information -compounds-, distributed among the number of different possible values -scaffolds-presented in the particular data set. The molecular similarity is a measure of the diversity of compounds within each database, in this case, according to their ECFP4 representation. CSP3 and chiral centers are different estimations of molecular complexity. The NPL score was computed according to the methods section.