Used in the synthesis of camptothecin analogs, which are potent anticancer agents targeting topoisomerase I. This compound is a key intermediate featuring a tert-butyldimethylsilyl (TBS) protecting group at the 9-position, which enhances lipophilicity and facilitates synthetic manipulations while preserving the core structure for developing stable lactone forms. Commonly employed in medicinal chemistry to create derivatives with improved solubility, pharmacokinetic properties, and efficacy against solid tumors such as lung, colon, and breast cancers.