Antiviral agent 61 (compound Z40) is a potent antiviral agent. Antiviral agent 61 shows anti tomato spotted wilt virus (TSWV) activity with an EC 50 value of 252 µg/mL. Antiviral agent 61 increases the RNA expression of Ndufb9, COX6B, 7.1.2.2, E, COX5B, Ndufs4, and SDHB, decreases the RNA expression of Ndufb7, Ndufa5, and G.