- Act by accepting electrons from the early acceptors of Photo system- I (PS-I)and then reacting with oxygen to form superoxide.
- CMU-3-4’ chlorophenyl-1-1-dimethyl urea.
- DCMU-3-3-4’ dichlorophenyl-1-1-dimethyl urea.
- Non-cyclic photophosphorylation is inhibited by CMU& DCMU. Competing for the binding site of plastoquinone that is normally occupied by QB.