Bemis-Murcko Framework with loose algorithm is calculated by removing side chains from the input structure. Exocyclic non-single bonded atoms are kept. Remaining bond types are not changed. We analyzed commercially available compounds and calculated Bemis-Murcko Frameworks.
Top building block frameworks were calculated from commercially available building blocks listed in the MolPort database. The 3000 most frequently found frameworks are listed below. They are sorted by heavy atom count from smallest to largest and by molecular weight (smallest to largest).