We have developed β-lactam peptidomimetic inhibitors of flaviviral proteases with a molecular weight between 340 and 500 that are active in a cellular assay in the single-digit micromolar range, combined with low cytotoxicity and low off-target interference. A key structural element of the compound class is the inclusion of a β-lactam moiety in the structural backbone.
The β-lactam ring facilitates a large variation of substituents as well as 3D organization of the pharmacophore. Therefore, we are confident that this strategy opens a route to inhibitors of other proteases, such as the SARS-CoV-2 protease or TMPRSS2 that are crucial for entry and replication of SARS-CoV-2.

