Ureas with histamine H3-antagonist receptor activity—A new scaffold discovered by lead-hopping from cinnamic acid amides

A group of tri and tetrasubstituted urea derivatives have been found to be hH3-antagonists. The most potent compounds were found in the class of (piperazine-1-yl)-(piperidine-1-yl)-methanones which in addition showed negligible hERG inhibition.