Sedanonic anhydride

The anhydride of sedanonic acid, Cj HjgOj, is not a lactone, but an anhydride resulting from the elimination of a molecule of water from a monobasic ketonic acid. Sedanonic anhydride occurs in oil of celery. The acid, which melts at 113°, has the following constitution —... 

Celery contains 1.5—3.0% volatile oil, primarily containing about 60—70% d-limonene and 10—20% /i-selinene. The characteristic celery odour is thought to be due to oxygenated compounds present in the oil (sedanolide and sedanonic acid anhydride). Essential oil of celery seed is available however, the most common extractive form is the oleoresin, due to its fuller flavour. This product contains 12—16% volatile oil. 

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