Approaches to virtual library design

Diversity-based and structure-based approaches to the design of virtual libraries are reviewed. Virtual library design arises in the development of screening libraries, as well as libraries directed at optimizing a particular biological activity. The authors review the thought processes behind different design approaches, and summarize the practical success that some have reported. The major controversies in the field are highlighted, and the assumptions underlying most of these methods are critically analyzed. Reflecting the balance of literature in the field, the majority of this review describes diversity-based approaches, while the rest describes the emerging techniques in 'structure-based combinatorial chemistry'.