Mps1-IN-3 is primarily used in research settings to study its role as an inhibitor of the Mps1 (Monopolar Spindle 1) kinase, which is crucial for cell division and chromosome alignment. By inhibiting Mps1, researchers can investigate its effects on cell cycle regulation, particularly in cancer cells, to understand potential therapeutic applications. This compound is valuable in exploring mechanisms of mitotic checkpoint control and identifying strategies to disrupt tumor growth. It is also utilized in preclinical studies to assess its efficacy and selectivity in targeting cancer cells while minimizing damage to normal cells.