In drug design, the concept of chemical similarity (or chemical diversity) has been addressed using different approaches, and its applications are mainly found in ligand-based design, for instance, in identifying bioactive compounds when some active compounds are known. Similarly, chemical similarity/diversity analysis provides useful information for projects that seek to prioritize the selection of potentially active compounds for experimental evaluation. Another application is the profiling and selection of compound collections with chemically diverse structures to increase the probability of identifying new scaffolds that can lead to specific biological targets . Similarity and diversity analyses have also been integrated into de novo design strategies to evaluate the structural and molecular novelty of chemical libraries, which play an important role in fairly comparing generative approaches .