4YYL:
reference: Structural and computational study on inhibitory compounds for endonuclease activity of influenza virus polymerase., Fudo S, Yamamoto N, Nukaga M, Odagiri T, Tashiro M, Neya S, Hoshino T, Bioorg Med Chem. 2015 Sep 1;23(17):5466-75. doi: 10.1016/j.bmc.2015.07.046. Epub , 2015 Jul 29. PMID: 26252962

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