The benefits of constructing leads from fragment hits.

'Fragments' refer to particularly small molecular starting points in medicinal chemistry. The small size of fragments requires adapted techniques for their screening and subsequent elaboration. The detection of the weak binding affinity of fragments for their target, and associated screening issues, have been debated at length. Since it is now clear that fragments can be developed into clinical candidates, the discussion is shifting to the design of good-quality lead compounds from fragment hits. The increasing ability to control and tailor this construction process highlights the potential benefits of fragment-based drug discovery.