AZ-23 is a potent and selective inhibitor of Checkpoint kinase 1 (Chk1), primarily utilized in medical research for cancer treatment studies. Chk1 plays a key role in DNA damage response and cell cycle checkpoints, making AZ-23 valuable for investigating pathways involved in cell proliferation and survival. Researchers use AZ-23 to explore its potential in sensitizing tumor cells to DNA-damaging therapies and halting abnormal cell growth. It is employed in preclinical studies to develop novel anticancer agents and in biochemical assays to assess efficacy, selectivity, and mechanisms across various cancer types, contributing to targeted oncology drug discovery and optimization.