NP-likeness scoring workflow. This workflow takes input of atom signatures file of natural product (NP Signatures), synthetic (SM Signatures), and query (Query Signatures) compounds dataset. The Natural product likeness calculator indexes the natural product and synthetic molecule signatures internally and generate NP-likeness scores for query compounds based on the presence or absence of its atom signatures in the index. The higher the score, the higher is the NP-likeness of the compound. The scores assigned with the corresponding compound UUID are written out to a text file. The UUID of the score can then be matched with the tagged structures (Shown in Figure 1) to retrieve the full structure. The Plot Distribution As PDF worker is helpful in visualising the distribution of compound scores in a dataset. The scorer worker also rebuilds fragment structure from the atom signature and assigns its corresponding fragment score as the fragment property. These fragment structures are written out to a SDF file as it is helpful in obtaining structures of high scoring fragments. The 2D Coordinates Generator is an optional worker to visualise the re-built fragments from the atom signature. This workflow is available for free download athttp://www.myexperiment.org/workflows/2121.html.