Parallel synthesis of potent, pyrazole-based inhibitors of Helicobacter pylori dihydroorotate dehydrogenase.

The identification of several potent pyrazole-based inhibitors of bacterial dihydroorotate dehydrogenase (DHODase) via a directed parallel synthetic approach is described below. The initial pyrazole-containing lead compounds were optimized for potency against Helicobacter pylori DHODase. Using three successive focused libraries, inhibitors were rapidly identified with the following characteristics: K(i) < 10 nM against H. pylori DHODase, sub-microg/mL H. pylori minimum inhibitory concentration activity, low molecular weight, and >10 000-fold selectivity over human DHODase.