Used as a key intermediate in the synthesis of epidermal growth factor receptor (EGFR) inhibitors, particularly in targeted cancer therapies. Its structure allows for selective modification at the 4-position and 7-position, making it valuable in developing tyrosine kinase inhibitors. Commonly employed in pharmaceutical research for lung, breast, and glioblastoma cancer drug candidates. Also utilized in structure-activity relationship (SAR) studies to optimize potency and selectivity of quinazoline-based drugs.