Used as an intermediate in organic synthesis, particularly in the preparation of complex organic molecules requiring selective alkylation. Its protected malonate structure allows controlled carbon chain extension in pharmaceutical synthesis. The tosyloxy group serves as a good leaving group, enabling nucleophilic substitution reactions to form carbon-carbon bonds. Commonly employed in the development of bioactive compounds, including potential drug candidates where precise molecular architecture is critical. Stable under a variety of reaction conditions, making it suitable for multi-step synthetic routes.