Fiammengo Roberto, Wojciechowski Kamil, Crego-Calama Mercedes, Timmerman Peter, Figoli Alberto, Wessling Matthias, Reinhoudt David N
Laboratory of Supramolecular Chemistry and Technology, MESA(+) Research Institute, and Membrane Technology Group, Department of Chemical Technology, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands.
Org Lett. 2003 Sep 18;5(19):3367-70. doi: 10.1021/ol030053w.
[structure: see text] Water-soluble models of heme-protein active sites are obtained via the self-assembly of cationic porphyrins 1 and tetrasulfonato calix[4]arene 2 (K(1.2)() = 10(5) M(-)(1)). Selective binding of ligands either outside or inside the cavity of assemblies 1.2 via coordination to the zinc center has been observed. Small ligands such as 4-methylpyridine and 1-methylimidazole are encapsulated, while the bulkier caffeine is bound outside. Assemblies Co-1.2, in which the Zn porphyrin moiety has been replaced by a Co(II) porphyrin, can act as O(2) carriers.