Rapid discovery of potent sulfotransferase inhibitors by diversity-oriented reaction in microplates followed by in situ screening

Rapid diversity-oriented microplate library synthesis and in situ screening with a high-throughput fluorescence-based assay were used to develop potent inhibitors of β-arylsulfotransferase IV (β-AST-IV). This strategy leads to facile inhibitor synthesis and study as it allows protecting-group manipulation and product isolation from other library components to be avoided. Through repeated library formation, three aspects of inhibitor makeup, the identities of the two binding groups and the length of the linker between AKthem, were independently optimized. Several potent inhibitors were obtained, one of which was determined to have an inhibition constant K; of 5 nm. This compound is the most potent β-AST-IV inhibitor developed to date, with a K; value more than five orders of magnitude lower than the Michaelis constant K_m for the substrate whose binding it inhibits.