Fumaric Acid tert-Butyl Ester is a tert-Butyl ester derivative of Fumaric Acid (F500380). Fumaric Acid tert-Butyl Ester is a reactant used in the preparation of cysteine protease inhibitors based on fumaric acid-derived oligopeptides. It is also used in the preparation of Nε-fumaroylated diketopiperazine of L-Lys used for pulmonary drug delivery.Solubility:Chloroform, Dichloromethane, Ethyl Acetate, Methanol