Oxaloacetic acid

Oxaloacetic acid also known as oxosuccinic acid or oxalacetic acid is a four-carbon dicarboxylic acid appearing as an intermediate of the citric acid cycle. In vivo oxaloacetate (the ionized form of oxaloacetic acid) is formed by the oxidation of L-malate catalyzed by malate dehydrogenase and reacts with Acetyl-CoA to form citrate catalyzed by citrate synthase. (wikipedia) A class of ketodicarboxylic acids derived from oxalic acid. Oxaloacetic acid is an intermediate in the citric acid cycle and is converted to aspartic acidD by a transamination reaction.