Their simple yet functionalized structures make them vital scaffolds in synthesizing many drugs and biologically active compounds, including anti-cancer drugs.3,4 Derivatives of pyrimidine moiety were known to mimic the natural pyrimidines and interfere with many important biological targets, making them a vital scaffold in the synthesis of novel anti-cancer agents.5 Several protein kinase inhibitors (PKIs) are discovered with amine-substituted pyrimidines as their bioactive core (Fig. 1).6–8. The gene discussed is WEE1; the disease is cancer.