When the “Precursors quinoid compounds” alert is found in your target by OFG profiler, this indicates that a quinoid-type compounds could be produced after some (a)biotic activation of this structure. In other words “Precursors quinoid compounds” alerts catches the chemicals which possess some potential to be transformed later to the active quinoide type compounds.

For example CAS RN 97-53-0 Eugenol is found as Precursor quinoid compound by OFG profiler. The latter stage is confirmed by Dufrasne, et.al. (see the attached article).