Synthesis of adjacent-bridged benzo-annelated cyclam and studies of mono- and di-benzo-annelated cyclam derivatives

A new synthetic methodology for the preparation of a novel adjacent-bridged benzoannelated cyclam is presented. This methodology utilizes reductive ring expansion followed by deallylation to give the desired adjacent-bridged benzo-annelated cyclam. This novel ligand is designed to complex metal cations with a trans coordination geometry. Derivatives of this ligand can be prepared by attaching pendant arms on the nitrogens which can aid as coordinating arms and linkers for potential use of this ligand as bifunctional chelator (BFC). Coupling chemistry studies have been carried out in an attempt to increase the lipophilicity of a dibenzo-annelated tetracyclic bisaminal and to functionalize at the para positions to provide a site for bio-conjugation