Such fragments were obtained by removing the common cores from each ligand series in the dataset and decomposing the remainders into chemical groups with the BRICS algorithm as implemented in the RDKit version 2021.03.3 while keeping track of the atoms bonding to the cores and to other fragments. This resulted in two groups of fragments: linkers (Fig. ), which directly bond to the cores, and termini (Fig. ), which bond to the linkers. The library R-groups were assembled by attaching each linker to the core by the same atom it would attach to the cores in the original dataset from Part I. Different numbers and combinations of termini were then added to the the designated linker's atoms.