Metabolism-guided structural modification

The rapid structure identification of metabolites provides an early perspective on the metabolically labile sites or soft spots of a drug candidate [86], This information is useful during lead optimization and can serve to initiate research efforts that deal with metabolism-guided structural modification and toxicity. 

This type of information about a homologous series of drug candidates, when considered in light of the propensity of these compounds to undergo first-pass metabolism and/or liver clearance, allows pharmaceutical scientists to make more intelligent decisions about which compounds to move into animal studies. In addition, when an in vitro-in vivo correlation can be demonstrated for a series of compounds, the results of Caco-2 experiments can be used as a guide by medicinal chemists to make structural modifications to optimize oral bioavailability. 

---