acid anhydrides

https://doi.org/10.1351/goldbook.A00072
Compounds consisting of two @A00123@ bonded to the same oxygen atom acyl-O-acyl. Symmetric and mixed @A00354@ have identical and different @A00123@, respectively. E.g.
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acetic anhydride,
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acetic benzenesulfonic anhydride,
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(thiobenzoic) anhydride.
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1311 [Terms] [Paper]