MAT2A inhibitor 6 (Compound 3N-h) is a specific MAT2A inhibitor with oral activity and yellow fluorescence ( IC 50 =26 nM), capable of visualizing MAT2A both in vitro and in vivo (λex = 430 nm, λem = 585 nm). MAT2A inhibitor 6 can induce apoptosis and has anticancer activity, which can be used in cancer research.