酸酐是某含氧酸脱去一分子水或几分子水，所剩下的部分。一般无机酸是一分子的该酸，直接失去一分子的水就形成该酸的酸酐，其酸酐中决定酸性的元素的化合价不变。而有机酸是两分子该酸或多分子该酸通过分子间的脱水反应而形成的。只有含氧酸才有酸酐。无氧酸是没有酸酐的。
6,7-Dimethoxy-1H-benzo[d][1,3]oxazine-2,4-dione
5-Bromo-1H-benzo[d][1,3]oxazine-2,4-dione
Ethyl 3-oxo-3-(2,3,4,5-tetrafluorophenyl)propanoate
2,2,3,3,4,4,4-Heptafluorobutanoic anhydride
Heptanoic anhydride
4-Sulfo-1,8-naphthalic Anhydride Potassium Salt
6-(2,5-Dioxotetrahydrofuran-3-yl)-4-methyl-7,7a-dihydroisobenzofuran-1,3(3aH,6H)-dione
7-Nitro-1H-benzo[d][1,3]oxazine-2,4-dione
4-Methylbenzoic anhydride
4,7-Dichloro-1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid
Ethane-1,2-diyl bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate)
1H-Pyrido[2,3-d][1,3]oxazine-2,4-dione
6-Nitro-1H-benzo[d][1,3]oxazine-2,4-dione
4-Hydroxyisobenzofuran-1,3-dione
Furo[3,4-c]quinoline-1,3-dione
4-Fluorobenzoic anhydride
1H-Thieno[3,2-d][1,3]oxazine-2,4-dione
5,6,7-Trimethoxy-1H-benzo[d][1,3]oxazine-2,4-dione
5-Chloro-1-methyl-1H-benzo[d][1,3]oxazine-2,4-dione
5-Nitro-1H-benzo[d][1,3]oxazine-2,4-dione
(R)-Benzyl (2,5-dioxotetrahydrofuran-3-yl)carbamate
5-Chloro-1H-benzo[d][1,3]oxazine-2,4-dione
Dodecanoic anhydride
Thieno[3,4-c]furan-1,3-dione
cis-Tetrahydro-1H-cyclopenta[c]furan-1,3(3aH)-dione
5,6-Dimethoxyisobenzofuran-1,3-dione
4,7-Dichloroisobenzofuran-1,3-dione
2-Methyl-4-oxo-4H-pyran-3-yl isobutyrate
(S)-Benzyl (4-(2,5-dioxooxazolidin-4-yl)butyl)carbamate
4,5-Dichlorophthalic Anhydride
