ESR1 and cancer: Pyrazines contain a heterocyclic motif that interacts with a diverse set of targets such as p53, the estrogen receptor, and the vascular endothelial growth factor (VEGF) making them an attractive target in the treatment of multiple diseases such as various cancers (Browne et al., 1991; Kamal et al., 2011; Lalitha et al., 2016).