Positional Analogue Scanning: An Effective Strategy for Multiparameter Optimization in Drug Design

Minimizing the number and duration of design cycles needed to optimize hit or lead compounds into high-quality chemical probes or drug candidates is an ongoing challenge in biomedical research. Small structure modifications to hit or lead compounds can have meaningful impacts on pharmacological profiles due to significant effects on molecular and physicochemical properties and intra- and intermolecular interactions. Rapid pharmacological profiling of an efficiently prepared series of positional analogues stemming from the systematic exchange of methine groups with heteroatoms or other substituents in aromatic or heteroaromatic ring-containing hit or lead compounds is one approach toward minimizing design cycles (e.g., exchange of aromatic or heteroaromatic CH groups with N atoms or CF, CMe, or COH groups). In this Perspective, positional analogue scanning is shown to be an effective strategy for multiparameter optimization in drug design, whereby substantial improvements in a variety of pharmacological parameters can be achieved.