Rat intestinal metabolism of crufomate (4-tert-butyl-2-chlorophenyl methyl methylphosphoramidate).
Abstract Everted sacs of rat small intestine metabolized crufomate (4‐tert‐buty 1–2‐chloropheny 1 methyl ethylphosphoramidate) under in vitro conditions to form six 14C‐labeled metabolites in quantities sufficient for isolation and identification. These metabolites were 4‐tert‐butyl‐2‐chloropheny1 methyl phosphoramidate (25%), 2‐chloro‐4(2‐hydroxy‐1,1‐dimethylethyl)phenyl methyl methylphosphoramidate (19%), 2‐[3‐chloro‐4‐[ [ (methoxy) (methyl‐amino)phosphinyl]oxy]phenyl]‐2‐methylpropionic acid (2%), 4‐tert‐butyl‐2‐chlorophenol (0.8%) and its glucuronide (6%), and the aromatic glucuronide of 2‐chloro‐4(2‐hydroxy‐1,1‐dimethylethyl)phenol (1%). These intestinal metabolites may represent precursory stages in the overall metabolism of crufornate.