text: Cyclic sulfonic esters are called sultones. Two examples are propane-1,3-sultone and 1,4-butane sultone. Some sultones are short-lived intermediates, used as strong alkylating agents to introduce a negatively charged sulfonate group. In the presence of water, they slowly hydrolyze to the hydroxy sulfonic acids. Sultone oximes are key intermediates in the synthesis of the anti-convulsant drug zonisamide.
  Tisocromide is an example of a sultone.