Discovery of isoquinoline-tethered quinazoline derivatives with enhanced HER2 inhibition over EGFR.

Human epidermal growth factor receptor 2 (HER2) is a critical therapeutic target for HER2-positive or HER2-dependent cancers. While several HER2 kinase inhibitors have been identified, achieving high selectivity for HER2 over EGFR remains a significant challenge. In this study, we aimed to develop HER2-selective inhibitors with enhanced cellular activity.