Aryl Bis-Sulfonamide Inhibitors of IspF fromArabidopsis thalianaandPlasmodium falciparum

Abstract 2‐Methylerythritol 2,4‐cyclodiphosphate synthase (IspF) is an essential enzyme for the biosynthesis of isoprenoid precursors in plants and many human pathogens. The protein is an attractive target for the development of anti‐infectives and herbicides. Using a photometric assay, a screen of 40 000 compounds on IspF from Arabidopsis thaliana afforded symmetrical aryl bis‐sulfonamides that inhibit IspF from A. thaliana ( At IspF) and Plasmodium falciparum ( Pf IspF) with IC 50 values in the micromolar range. The ortho ‐bis‐sulfonamide structural motif is essential for inhibitory activity. The best derivatives obtained by parallel synthesis showed IC 50 values of 1.4 μ m against Pf IspF and 240 n m against At IspF. Substantial herbicidal activity was observed at a dose of 2 kg ha −1 . Molecular modeling studies served as the basis for an in silico search targeted at the discovery of novel, non‐symmetrical sulfonamide IspF inhibitors. The designed compounds were found to exhibit inhibitory activities in the double‐digit micromolar IC 50 range.