Tri- and bi-cyclic heteroaryl histamine-3 receptor ligands

摘要

Compounds of formula (I) wherein R₁ or R₂ is a tricyclic or bicyclic ring, each of which contains at least two heteroatoms, and R₁, R₂, R₃, R_3a, R_3b, R₄, R₅, L, X, X', Y, Y', Z, and Z' are as defined herein, are useful in treating conditions or disorders prevented by or ameliorated by histamine-3 receptor ligands. Also disclosed are pharmaceutical compositions comprising the histamine-3 receptor ligands, methods for using such compounds and compositions, and a process for preparing compounds within the scope of formula (I).