[Orb Pilot Scale up Reactor: Image from Syrris]
Flow chemistry techniques are increasingly being used in drug discovery to provide cost-effective access to a wide range of structurally diverse small molecule analogs, as well as access to previously underused or inaccessible chemistries. There are several ways that this powerful technique can be used to increase structural diversity when building candidate molecules, including linear progression from diverse starting materials, multicomponent reactions around core structural motifs, synthesis of uncommon low diversity starting material sub-sets, and convergent synthesis approaches. The diversity of the starting components is a key consideration when deciding the most suitable strategy for each specific application, but the development of automated, modular flow chemistry systems has made all these approaches far easier to achieve. Here we outline the various methods and…