Pillar[5]arene derivatives bearing peripheral porphyrin subunits have been efficiently prepared from a deca-azide pillar[5]arene building block (17) and Zn -porphyrin derivatives bearing a terminal alkyne function (9 and 16). For the resulting deca-Zn -porphyrin arrays (18 and 20), variable temperature NMR studies revealed an intramolecular complexation of the peripheral Zn -porphyrin moieties by 1,2,3-triazole subunits. As a result, the molecules adopt a folded conformation. This was further confirmed by UV/Vis spectroscopy and cyclic voltammetry. In addition, we have also demonstrated that the coordination-driven unfolding of 18 and 20 can be controlled by an external chemical stimulus. Specifically, addition of an imidazole derivative (22) to solution of 18 or 20 breaks the intramolecular coordination at the origin of the folding. The resulting molecular motions triggered by the addition of the imidazole ligand mimic the blooming of a flower.

As ophisticated photoactive molecular device has been prepared by combiningr ecent conceptsf or the preparation of multifunctional nanomolecules (click chemistry on multifunctional scaffolds) with supramolecular chemistry (self-assembly to prepare rotaxanes). Specifically,aclickable [2]rotaxane scaffold incorporating af ree-base porphyrin stopperh as been prepared and functionalized with ten peripheralZ n(II)-porphyrinm oieties. Electrochemical investigations of the final compound revealed ap eculiar behavior resultingf rom the intramolecular coordinationo ft he Zn(II) porphyrin moieties to 1,2,3-triazoleu nits. Finally,s teady state investigationso ft he compound combining Zn(II) and free-base porphyrin moieties have shown that this compoundi salight-harvesting device capable of channeling the light energy from the peripheralZ n(II)-porphyrins ubunits to the core by singlet-singlet energy transfer.

A dramatic enhancement in the glycosidase multivalent inhibitory effect was observed while going from a dodecavalent iminosugar ball to the corresponding giant molecule with 120 peripheral subunits.