Expanding the medicinal chemistry synthetic toolbox

Analysis of the role of synthetic organic chemistry in the identification of chemical starting points for drug discovery and subsequent optimization into candidate drugs indicates that a small number of reactions and commercially available building blocks dominate. This Perspective highlights opportunities for expanding the synthetic toolbox of medicinal chemists, potentially enabling the more effective exploration of therapeutically relevant chemical space. The key objectives of medicinal chemistry are to efficiently design and synthesize bioactive compounds that have the potential to become safe and efficacious drugs. Most medicinal chemistry programmes rely on screening compound collections populated by a range of molecules derived from a set of known and robust chemistry reactions. Analysis of the role of synthetic organic chemistry in subsequent hit and lead optimization efforts suggests that only a few reactions dominate. Thus, the uptake of new synthetic methodologies in drug discovery is limited. Starting from the known limitations of reaction parameters, synthesis design tools, synthetic strategies and innovative chemistries, here we highlight opportunities for the expansion of the medicinal chemists' synthetic toolbox. More intense crosstalk between synthetic and medicinal chemists in industry and academia should enable enhanced impact of new methodologies in future drug discovery.