Utilizing the tricyclic bisaminal 1 as a versatile building block, various N-functionalized cross-bridged tetraazamacrocycles 2 can be synthesized. 1 can also be used for the synthesis of C-functionalized tetracyclic bisaminal intermediates such as 3. Introduction of the exo-methylene in 3 provides a handle for additional chemical modifications. Progress in this area will be discussed and current limitations will be presented.