Novel family of fused tricyclic [1,4]diazepines: Design, synthesis, crystal structures and molecular docking studies

An efficient one-pot strategy for the synthesis of a new family of imidazo[1,4]diazepines has been developed and its mechanism has been proposed, which follows a seven-membered ring closure reaction. The condensation of 2- and 4-imidazolecarboxaldehyde with pyrazole amines provides six compounds 1–6, which are based on two types of fused tricyclic scaffolds. All presented compounds were fully spectroscopically characterized and their structure was unambiguously determined by single crystal X-ray crystallography. Molecular docking studies reveal a high similarity between binding modes of diazepines 1, 6 and eticlopride in the dopamine D3 receptor, as well as between enantiomers 2S, 6S and nortriptyline in dopamine transporter DAT.