Novel imidazobenzazepine derivatives as dual H1/5-HT2A antagonists for the treatment of sleep disorders

A novel imidazobenzazepine template (5a) with potent dual H(1)/5-HT(2A) antagonist activity was identified. Application of a zwitterionic approach to this poorly selective and poorly developable starting point successfully delivered a class of high quality leads, 3-[4-(3-R(1)-2-R-5H-imidazo[1,2-b][2]benzazepin-11-yl)-1-piperazinyl]-2,2-dimethylpropanoic acids (e.g., 9, 19, 20, and 21), characterized by potent and balanced H(1)/5-HT(2A) receptor antagonist activities and good developability profiles.