Exploring target-selectivity patterns of molecular scaffolds.

We investigate the question of whether target-selective molecular scaffolds can be identified on the basis of currently available compound activity data. Starting from a pool of 17745 public domain compounds with activity annotations for 433 human targets, we ultimately identify, through a selectivity classification and database-mining approach, 42 molecular scaffolds represented by multiple compounds that are highly selective for a particular target over one or more others. In many other cases, individual compounds representing unique scaffolds are target-selective. Hence, currently available public domain compound selectivity data are sparse. However, we also identify selectivity patterns that evolve around specific targets and are formed by multiple target-selective scaffolds. These scaffolds should provide interesting starting points for further chemical exploration.