Background
Redox cycling compounds have been reported to cause false positive inhibition of proteases in drug discovery studies. This kind of false positives can lead to unusually high hit rates in high-throughput screening campaigns and require further analysis to distinguish true from false positive hits. Such follow-up studies are both time and resource consuming.
Conclusions
In this study we report that compounds containing the 4-aminophenol moiety inactivate cysteine cathepsins through a redox-based mechanism and are thus likely to cause false positive hits in the screening assays for cysteine proteases.