Compounds having the structure RS(=O)2OS(=O)2R', e.g. PhS(=O)2OS(=O)2Ph benzenesulfonic anhydride.
See also:
acid anhydrides
Source: PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1369 [Terms] [Paper]