Vinclozolin M2 and M1 are metabolites of vinclozolin, a dicarboximide fungicide widely used in the United States and Europe for control of diseases caused by B. cineera, S. sclerotiorum, and Monilinia species in fruits, grapes, ornamental plants, turfgrass and vegetables. M1 and M2, are effective antagonists of the androgen receptor in rats exhibiting Ki values of 92 and 9.7 μM respectively. In fathead minnow, M1 and M2 failed to compete for high-affinity, low capacity testosterone binding sites in brain and ovary cytosolic fractions suggesting that they are not anti-androgens in this species.
