Ethoxycarbonyl isothiocyanate is primarily used as a versatile reagent in organic synthesis, particularly in the preparation of heterocyclic compounds. It is commonly employed in the synthesis of thioureas, which are valuable intermediates in the production of pharmaceuticals and agrochemicals. The compound is also utilized in the modification of peptides and proteins, enabling the introduction of thiocarbonyl functional groups for further chemical transformations. Additionally, it finds application in the development of biologically active molecules, including potential drug candidates, due to its ability to react with amines and other nucleophiles to form stable derivatives. Its role in the synthesis of sulfur-containing compounds makes it a key reagent in medicinal chemistry and material science research.