Shie et al. 131  reported another series of peptide inhibitors with comparatively reduced molecular weight to increase drug‐like properties. These pseudo‐C2‐symmetric inhibitors consist of a Phe‐Phe‐dipeptidic α,β‐unsaturated ester. One of these inhibitors (39) had an outstanding inhibitory activity with an EC50 value of 0.52 µM (see Figure 12). Besides, it displayed remarkable antiviral activity with an EC50 value of 0.18 µM. Structurally, the presence of 4‐dimethylamine on the phenyl ring was found to be crucial for activity enhancement.