The search for exact matches in ChEMBL (1,782,229 molecules) revealed that only 298 of the over 6.7 million recombined molecules have already been described in ChEMBL. Only 218 matching molecules remain after removing the exact and substructure matches in the "reduced original ligands" used for the fragmentation. Consulting bioactivity data available in ChEMBL, 47 out of these 218 molecules have been shown to be active against human target(s) (activity is here defined as IC 50 ≤ 500 nM): 44 are active against kinases, two against cytochrome P450, and one against an voltage-gated ion channel. In total, 10 molecules show a high activity against kinases with an IC 50 ≤ 5 nM (see Figure ). More details on the ChEMBL IDs and molecular structures are shown in Table and Figure . This shows strong evidence that the library contains molecules with a high chance of exhibiting kinase activity.