Novel 1-(azacyclyl)-3-arylsulfonyl-1H-pyrrolo[2,3-b]pyridines as 5-HT6 agonists and antagonists

Indoles 1 are 5-HT6 receptor ligands with modest 5-HT6 functional activities. Azaindoles 2 have enhanced 5-HT6 affinities and functional activities. Constraining the basic side chain provided 5-HT6 ligands (3 and 4) with high binding affinities.