BVDV-IN-1 is a potent non-nucleoside inhibitor of the bovine viral diarrhea virus (BVDV) RNA-dependent RNA polymerase (RdRp), exhibiting antiviral activity with an EC50 of 1.8 µM. It binds a hydrophobic pocket on the RdRp and retains efficacy against strains resistant to thiosemicarbazone-class NNIs, making it a valuable tool for antiviral mechanism and resistance studies.