acetoacetic acid /as′ətō·əsē″tik, əsē′tō-/ , a colorless, oily keto acid produced by the metabolism of lipids and pyruvates. It is excreted in trace amounts in normal urine and in elevated levels in diabetes mellitus, especially in ketoacidosis. Acetoacetic acid levels are also increased during starvation as a result of the incomplete oxidation of fatty acids. Soluble in water, alcohol, and ether, acetoacetic acid decomposes at temperatures below 100° C to acetone and carbon dioxide. Also called acetone carboxylic acid, acetylacetic acid, beta-ketobutyric acid, diacetic acid.
