Previous research on histamine H3 antagonists has led to the development of a pharmacophore model consisting of a central phenyl core flanked by two alkylamine groups. Recent investigation of the replacement of the central phenyl core with heteroaromatic fragments resulted in the preparation of novel 3, 5-, 3, 6-and 3, 7-substituted indole and 3, 5- substituted benzothiophene analogs that demonstrate good to excellent hH3 affinities. ...