Used in the synthesis of barbiturates, malonic acid serves as a key building block in pharmaceuticals. It plays a role in the preparation of vitamins B1 and B6, and is involved in the production of certain dyes and fragrances. In organic chemistry, it is commonly used in condensation reactions, such as the Knoevenagel reaction, to form carbon-carbon bonds. It also finds use in electroplating baths to improve metal deposit uniformity and in polymerization inhibitors for vinyl compounds. Additionally, malonic acid is employed in some biodegradable chelating agents and as a component in specialty esters for plasticizers.