Sulfonylurea compounds which contain dihydroisobenzofuran, dihydroisobenzothiophene, or isoindoline 4-sulfonamide substituents such as 1,3-dihydro-N-[(4-methoxy-6-methylpyrimidin-2-yl)aminocarbonyl]benzo[c] furan-4-sulfonamide and their use as agricultural chemicals, including plant growth regulants and herbicides.