Molecules passing both steps were considered as hits. This approach has recently been implemented in Sachem storing fingerprint data in an experimental Lucene implementation ported to C. In this study, a standard Lucene implementation in Java 1.8 was used with fingerprint libraries pattern fingerprinter (RDKit), DescriptorHandlerLongFFP512 (OCL) and CDKFingerprinter (CDK). The pattern fingerprint of RDKit uses SMARTS pattern to generate topological fingerprints of molecules . The DescriptorHandlerLongFFP512 of OCL is a binary fingerprint that depends on a dictionary of 512 predefined structure fragments . The CDKFingerprinter generates one-dimensional bit arrays, where bits are assigned based on the presence of a certain structural feature in a compound . The molecules were normalized using the options available in OCL and CDK, and the molVS standardizer for RDKit.