Figure 1.

Virtual combinatorial libraries. (Upper) Schematic representation of the casting process: receptor-induced self-assembly of the complementary substrate from a collection of components/fragments. This process amounts to the selection of the optimal substrate from a virtual substrate library. (Lower) Schematic representation of the molding process: substrate-induced self-assembly of the complementary receptor from a collection of structural components/fragments. This process amounts to the selection of the optimal receptor from a virtual receptor library. The diverse potential constituents of the libraries (Center) are either covalently linked or noncovalently bound reversibly generated species that may or may not exist in significant amount(s) in the free state, in absence of the partner.