CCT245737 is a potent and selective inhibitor of CHK1 (Checkpoint kinase 1), a key protein involved in the DNA damage response pathway. It is primarily used in cancer research to investigate mechanisms of cell cycle control and DNA repair. By inhibiting CHK1, CCT245737 abrogates cell cycle arrest, forcing cancer cells with damaged DNA to enter mitosis prematurely, leading to cell death. This makes it a valuable tool for studying synthetic lethality, especially in combination with DNA-damaging agents such as chemotherapy or radiation. It has shown enhanced cytotoxic effects in p53-deficient cancer cells, which are often more reliant on CHK1 for survival. Due to its ability to sensitize tumor cells to genotoxic stress, CCT245737 is widely used in preclinical studies to evaluate combination therapies aimed at improving anticancer efficacy and overcoming drug resistance.