Aconitic acid is an organic acid. The two isomers are cis-aconitic acid and trans-aconitic acid. The conjugate base of cis-aconitic acid, cis-aconitate is an intermediate in the isomerization of citrate to isocitrate in the citric acid cycle. It is acted upon by the enzyme aconitase.

Aconitic acid[1]
Cis-aconitic acid.png
cis-aconitic acid
Trans-aconitic acid.png
trans-aconitic acid
IUPAC name
Prop-1-ene-1,2,3-tricarboxylic acid
Other names
Achilleic acid; equisetic acid; citridinic acid; pyrocitric acid; achilleaic acid; acinitic acid
ECHA InfoCard 100.007.162
  • 309 (cis and trans)
Molar mass 174.108 g·mol−1
Appearance Colorless crystals
Melting point 190 °C (374 °F; 463 K) (decomposes) (mixed isomers), 173 °C (cis and trans isomers)
Acidity (pKa) 2.80, 4.46 (trans isomer)[2]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Aconitic acid can be synthesized by dehydration of citric acid using sulfuric acid:[3]


A mixture of isomers are generated in this way.

It was first prepared by thermal dehydration.[4]


  1. ^ "Aconitic Acid - Compound Summary (CID 309)". PubChem.
  2. ^ Dawson, R. M. C.; Elliott, D. C.; Elliott, W. H. (1989). Data for Biochemical Research (3rd ed.). Oxford: Clarendon Press. ISBN 9780198552994.
  3. ^ Bruce, W. F. (1937). "Aconitic Acid". 17: 1. doi:10.15227/orgsyn.017.0001.
  4. ^ Pawolleck, B. (1875). "Substitutionsproducte der Citronensäure und ein Versuch zur Synthese der letzteren" [Substitution products of citric acid and an attempt at the synthesis of the latter]. Justus Liebig's Annalen der Chemie. 178 (2–3): 150–170. doi:10.1002/jlac.18751780203.