PmV inhibitory activity of the generated compounds (1^st set).

IC₅₀ values, obtained in the presence of 3 μM of HRPII-PExEl substrate, are shown. They are averages of not less than three independent inhibition curves. Standard errors of the calculation of the IC₅₀s by sigmoidal fitting are shown in column ‘±’. HEA indicates the hydroxyethylamino group that links P₁, the non-amino acidic leucine analog, (3S)-3-amino-2-hydroxy-5-methylhexyl- group, and P₁', the alanine. HnV is hydroxynorvaline, a non-natural amino acid. Relevant modifications of 1 as follows: Panel a, C-terminus; b, P₁'; c, P₂'; d, P₂; e, P₃. Amino acids are three-letter and colour coded except for ‘[Leu-HEA-…]’ corresponding to the (3S)-3-amino-2-hydroxy-5-methylhexyl- group, as follows: hydrophobic amino acids (aa) are in shades of yellow; aromatic aa, orange; positively charged aa, purple; polar aa, blue; and acidic aa, grey. NS = Not significant; ND = not determined; NA = not applicable.