Used primarily in the synthesis of pharmaceutical intermediates, especially in the development of phosphodiesterase (PDE) inhibitors. It plays a key role in creating compounds with potential for treating cardiovascular and pulmonary diseases due to its ability to modulate enzyme activity involved in cellular signaling. Its sulfonic acid group enhances water solubility, making it valuable in improving the bioavailability of active pharmaceutical ingredients. Also utilized in research settings to develop analogs with optimized metabolic stability and target selectivity.