A significant impediment in automating this technique is the requirement for postreaction purification. This article discusses a series of solid-phase scavengers that provide rapid, postreaction flowthrough cleanup after each step of a multistep synthesis. An underlying objective in drug discovery research is to target a disease process at the molecular level by preparing and screening a large number of stable compounds of interest. There are a number of approaches to purifying reaction mixtures before screening. Parallel Synthesis Parallel synthesis employs automation for many individual, simultaneous multistep syntheses.
Flowthrough blocks make possible the simultaneous purification of multiple samples.
Multiple samples also can be processed in parallel, using automated platforms for SPE-style cartridges. Analysts apply a vacuum to pull the reaction mixture through the scavenger and into the collection plate. Given a kinetically efficient scavenger, flowthrough scavenging can be accomplished in minutes versus hours for bulk methods. Modern parallel robotic synthesizers can prepare chemical libraries of many hundreds of compounds per day. The immobilized reactant is then subjected to a series of chemical reactions to prepare the desired end product.