3H-2,1-Benzoxathiol-3-one, 1,1-dioxide 81-08-3 Benzoic acid, 2-sulfo-, cyclic anhydride Benzoic acid, o-sulfo-, cyclic anhydride NSC49162 Sulfobenzoic anhydride o-Sulfobenzoic acid anhydride o-Sulfobenzoic acid, cyclic anhydride o-Sulfobenzoic anhydride