A new class of diamine-based human histamine H3 receptor antagonists:: 4-(aminoalkoxy)benzylamines

4-(Aminoalkoxy)benzylamines were prepared and screened for in vitro activity at the human histamine H-3 receptor. Some members of this series exhibited subanomolar binding affinities. Analogues in which one nitrogen atom was replaced with a methine group showed greatly reduced binding affinities. Six members of this series were found to be antagonists in a cell-based model of human histamine H-3 receptor activation. One member of this series, 1-[4-(3-piperidin-1-ylpropoxy)benzyljpiperidine (7b), was found to be a selective and potent human H-3 receptor antagonist.