Molecular fields in ligand discovery.

The discovery of novel biologically active small molecules is now a technologically and economically viable proposition for academic and small biotechnology laboratories wishing to build on their biological research into target proteins. Such small molecules may be useful reagents for further biological research or may form the basis for early-stage drug discovery. The availability of specialized virtual screening software to filter large molecular libraries into manageable numbers of compounds for biological assays is the driving force for finding novel ligands. The main focus of this chapter is the basis and use of molecular field methods to assess the interactions that may be made by small molecules. Molecular field based measures of capability and similarity of interaction may be used to discover novel ligands and expand ligand series for potential use as future therapies.