This reaction opens the benzene ring, which gives an imidazolinone ester . According to Los, this reaction was one that went wrong. It returned a product that differed from the formulations. Yet, this accident was to become the imidazolinone herbicide. Imidazolinones are special because they will only chemically bind to an enzyme that is present in plants.
Plants produce three amino acids , leucine, isoleucine and valine .
Imidazolinones block the enzyme that catalyzes amino acid biosynthesis. This prevents new cell growth and kills the weed. Humans and animals do not possess this biosynthetic pathway. Hence, imidazolinones are not toxic to humans or wildlife. Crops such as soybeans, wheat, barley and peanuts have been tested for resistance to imidazolinones.