4TN2:
reference: Design and synthesis of lactam-thiophene carboxylic acids as potent hepatitis C virus polymerase inhibitors., Barnes-Seeman D, Boiselle C, Capacci-Daniel C, Chopra R, Hoffmaster K, Jones CT, Kato M, Lin K, Ma S, Pan G, Shu L, Wang J, Whiteman L, Xu M, Zheng R, Fu J, Bioorg Med Chem Lett. 2014 Aug 15;24(16):3979-85. doi:, 10.1016/j.bmcl.2014.06.031. Epub 2014 Jun 20. PMID: 24986660

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