Clemastanin B, a lignin, has potent anti-influenza activities by inhibiting the virus multiplication, prophylaxsis and blocking the virus attachment. Clemastanin B targets viral endocytosis, uncoating or ribonucleoprotein (RNP) export from the nucleus. Clemastanin B has antioxidant and anti-inflammatory activities.

Clemastanin B inhibits different subtypes of human (H1N1, including swine-origin H1N1; H3N2 and influenza B) and avian influenza viruses (H6N2, H7N3, H9N2) at different magnitudes of activity (IC₅₀ 0.087-0.72 mg/ml) while this compound was inactive against respiratory syncytial virus (RSV), adenovirus 3 (ADV3), parainfluenza virus 3 (PIV3), enterovirus 71 (EV71) and human rhinovirus (HRV).
Clemastanin B (0.05, 0.1, 0.2, 0.4 mg/ml; for 8 hours) treatment results in nucleoprotein (NP) distribution in the nuclei in MDCK cells.
Clemastanin B (48-72 h) after virus incubation (MOI, 0.01; for 2 h) causes a pronounced titer reduction of progeny virus in MDCK cells.
Clemastanin B (pre-incubated for 2 h) has no protective effect on MDCK cell lines with influenza virus.

西域 has not independently confirmed the accuracy of these methods. They are for reference only.

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