Structure–Activity Relationship Studies of Substituted 2-Phenyl-1,2,4-triazine-3,5(2H,4H)-dione Analogues: Development of Potent eEF2K Degraders against Triple-Negative Breast Cancer

eEF2K, an atypical alpha-kinase, is responsible for regulating protein synthesis and energy homeostasis. Aberrant eEF2K function has been linked to various human cancers, including triple-negative breast cancer (TNBC). However, limited cellular activity of current eEF2K modulators impedes their clinical application. Based on the 2-phenyl-1,2,4-triazine-3,5(2