Pin1 might be a novel strategy for developing anticancer agents. Herein, a series of pyrimidine derivatives were synthesized and their Pin1 inhibitory activities were evaluated. Among them, four compounds (2a, 2f, 2h and 2l) displayed potent inhibitory activities against Pin1 with IC50 values lower than 3 µM. This series of pyrimidine-based inhibitors presented time-dependent inhibition against Pin1