Crosslinking agent for modification of proteins via amidationMalononitrile is used as a precursor in the preparation of anti-cancer drug, triamterene, adenine, methotrexate, thiamine, acrylic fibers and dyes. It is used in Knoevenagel condensation to prepare 2-chlorobenzalmalononitrile by reacting with 2-chlorobenzaldehyde. It acts as a leaching agent for gold. It is used as a raw material for the Gewald reaction of ketone or aldehyde to produce 2-aminothiophene using elemental sulfur and a base. Further, it plays an important role in the preparation of [1,6]-naphthyridines, gamma-ketoamides, 1,4-dihydropyridine, chromeno[2,3-b]pyridine and dihydro-1,4-dithiepine frameworks.