hSMG-1 kinase plays a dual role in a highly conserved RNA surveillance pathway termed nonsense-mediated RNA decay (NMD) and in cellular genotoxic stress response. Since deregulation of cellular responses to stress contributes to tumor growth and resistance to chemotherapy, hSMG-1 is a potential target for cancer treatment. From our screening efforts, we have identified pyrimidine derivatives as hSMG-1 kinase inhibitors. We report structure ...