N,N-Dimethyl-[9-(arylsulfonyl)-2,3,4,9-tetrahydro-1H-carbazol-3-yl]amines as novel, potent and selective 5-HT6 receptor antagonists

The design, synthesis and SAR of novel tetrahydrocarbazole derivatives having 5-HT6 receptor antagonist activity is presented. The racemic compound 15e was found to possess desirable pharmacokinetic properties, adequate brain penetration and activity in animal models of cognition.