Antiviral efficacy of potent AM2-S31N inhibitors in inhibiting clinically relevant human influenza A viruses. The antiviral efficacy was determined using plaque reduction assays. (A) Dose response curves of compounds 9a, 9d, 9f, and 9h in inhibiting the A/California/07/2009 (H1N1) virus. (A) Dose response curves of compounds 9q, 9s and 9v in inhibiting the A/California/07/2009 (H1N1) virus. (B) Dose response curves of compound 9q in inhibiting the A/California/07/2009 (H1N1), A/Washington/29/2009 (H1N1), A/Switzerland/9715293/2013 (H3N2), and A/Denmark/528/2009 (H1N1) viruses. Each data point represents duplicate experiments.