In this study we report on the design, synthesis, and biological evaluation of pyrrole-2-one 2 to be a highly potent VEGF-R2/3 inhibitor with IC50 of 31/37 nM. The novel 3, 4-diaryl-2 H- pyrrole-2-ones were designed on the basis of the modeled binding mode of the corresponding 1 H-pyrrole-2, 5-dione (maleimide) VEGF-R2/3 inhibitor 1 indicating two H- bond ligand− protein interactions in the ATP pocket for the amide 2 but not for the isomer 3 ...