Saccharin is a 1,2-benzisothiazole having a keto-group at the 3-position and two oxo substituents at the 1-position. It is used as an artificial sweetening agent. It has a role as a sweetening agent, a xenobiotic and an environmental contaminant. It is a 1,2-benzisothiazole and a N-sulfonylcarboxamide.