If we consider a schematic AT-CuAAC retrosynthesis of MGI-1 isomers (Figure ) and MAC enantiomers (Figure ), in which the axle is divided into two half-axle components that couple through the macrocycle in the forward synthesis, the common challenge involved in the stereoselective synthesis of both becomes obvious; we must control which face of the macrocycle is oriented towards which half-axle component in the mechanical bond forming step.