The present invention relates to the use of compounds which have the following general formula (I), wherein R1 and R2 are independently selected from optionally substituted aryl, optionally substituted C1 to C12 alkyl and H; and R3 and R4 are independently selected from hydroxy, optionally substituted C1 to C6 alkyl, optionally substituted phenyl and H, in a method of preventing or reducing fouling, particularly in the marine environment. The compounds of the present invention have the considerable advantage of providing the antifouling coating market with an organic alternative to the existing technology which relies heavily on the addition of copper to obtain significant antifouling effects. The compounds we have developed may be used as cheap, easy to prepare additives that do not contain metals and therefore have reduced toxicity in marine environment.