has role carotenoid biosynthesis inhibitor herbicide pyridazinone agrochemical organochlorine compound norflurazon CHEBI:50842 A pyridazinone that is pyridazin-3(2<em>H</em>)-one which is substituted at positions 2, 4, and 5 by <em>m</em>-(trifluoromethyl)phenyl, chloro, and methylamino groups, respectively. A pre-emergence herbicide used to control grasses and broad-leafed weeds in a variety of crops. Not approved for use within the European Union. secondary amino compound (trifluoromethyl)benzenes