We demonstrate a general method for the construction of M8L 4 tubular complexes via subcomponent self-assembly, starting from CuI or AgI precursors together with suitable elongated tetraamine and 2-formylpyridine subcomponents. The tubular architectures were often observed as equilibrium mixtures of diastereomers having two different point symmetries (D2d or D2 â‡ D4) in solution. The equilibria between diastereomers were influenced through variation in ligand length, substituents, metal ion identity, counteranion, and temperature. In the presence of dicyanoaurate(I) and AuI, the D 4-symmetric hosts were able to bind linear Au(Au(CN) 2)2- (with two different configurations) as the best-fitting guest. Substitution of dicyanoargentate(I) for dicyanoaurate(I) resulted in the formation of Ag(Au(CN)2)2- as the optimal guest through transmetalation. Density functional theory was employed to elucidate the host-guest chemistries of the tubes.