FIELD : medicine.SUBSTANCE : invention refers to medicine and chemical-pharmaceutical industry and concerns a new immunomodulatory and antiviral agent based on a hybrid molecule of triterpenoid-coumarin derivatives, namely (2-((coumarin-7-yl)oxy)ethyl) 3-hydroxy 20(29)-lupen-28-oate.EFFECT : declared compound has immunomodulatory properties, having an effect on activation of the humoral response, and expressed antiviral activity against influenza virus A/California/07/09 (H1N1)pdm09 in Balb/c mice in therapeutic and prophylactic mode of application in doses of 10 mg/kg, can be used in medical practice in treating and preventing viral infections.1 cl, 6 dwg, 2 tbl, 3 ex