Influenza virus-IN-2 (compound 19) is a potent influenza virus inhibitor with an EC 50 of 2.58 µM and CC 50 of 150.85 µM. Influenza virus-IN-2 shows a concentration dependent inhibition activity for PA N endonuclease with EC 50 of 489.39 nM. Influenza virus-IN-2 shows shows anti-influenza A virus activities.