Biotransformation of vinclozolin by the fungus Cunninghamella elegans

This study investigated the biotransformation of the dicarboximide fungicid e vinclozolin [3-(3,5-dichlorophenyl)-5-methyl-5-vinyl-1,3-oxazolidine-2,4- dione] by the fungus Cunninghamella elegans. Experiments with phenyl-[U-rin g-C-14]vinclozolin showed that after 96 h incubation, 93% had been transfor med to four major metabolites. Metabolites were separated by HPLC and chara cterized by mass and NMR spectroscopy. Biotransformation occurred predomina ntly on the oxazolidine-2,4-dione portion of vinclozolin. The metabolites w ere identified as the 3R- and 3S- isomers of 3',5'-dichloro-2,3,4-trihydrox y-2- methylbutyranilide, N-(2-hydroxy-2-methyl-1-oxobuten-3-yl)-3,5-dichlo- rophenyl-1-carbamic acid, and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanil ide. The enanilide compound has been reported previously as a plant and mam malian metabolite and is implicated to contain antiandrogenic activity. The 3R- and 3S- isomers of 3',5'-dichloro-2,3,4-trihydroxy-2-methylbutyranilid e are novel metabolites.