KDR and cancer: Prymidinone and pyrimidinthione are synthetic compounds that belong to the class of pyrimidine derivatives.49,50 Several derivatives are being explored for their ability to inhibit specific kinases involved in cancer progression, such as The receptors for vascular endothelial growth factor (VEGFR) and epidermal growth factor (EGFR).51,52 These inhibitors may enhance targeted cancer therapies.