METABOLIC FATE OF SIDURON IN ANIMAL

Three metabolites of siduron [1-(2-methylcyclohexyl)-3-phenylurea] were found in the urine of a dog fed this herbicide at a dietary level of 2500 p.p.m. over a 14-month period. These metabolites were identified as the conjugates of 1-(p-hydroxyphenyl)-3-(2-methylcyclohexyl)urea, 1-(4-hydroxy-2-methylcyclohexyl)-3-(p-hydroxyphenyl)urea, and 1-(4-hydroxy-2-methylcyclohexyl)-3-phenylurea. The free metabolites, after enzymatic hydrolysis and extraction, were isolated and characterized by thin-layer chromatographic, mass spectrometric, infrared spectrometric, and nuclear magnetic resonance techniques. A metabolic pathway for siduron is proposed. © 1969, American Chemical Society. All rights reserved.