Hidekazu Miyaji

The cis ‐dipyridylcalix[4]pyrrole palladium(II) complex ( cis ‐DPC+Pd ²⁺ ) forms a cage‐like supramolecular structure that functions as an ion channel, as evidenced by the single ion channel current observations. A lucigenin fluorescence assay revealed that cis ‐DPC+Pd ²⁺ transports chloride across membranes. The HPTS fluorescence assay revealed that cis ‐DPC+Pd ²⁺ selectively transports fluoride and chloride. In a cell proliferation assay using THP‐1 cells, the cell survival rate with cis ‐DPC+Pd ²⁺ was lower than that with trans ‐DPC or trans ‐DPC+Pd ²⁺ . These results suggest that cis ‐DPC+Pd ²⁺ causes cell death by forming supramolecular pores, allowing the passage of increased numbers of ions.

Artificial antenna complexes of metal‐coordinated bis(8‐hydroxyquinoline)‐substituted porphyrin networks that mimic antenna chromophores in plants were organized on titanium dioxide electrodes in photoelectrochemical cells. The generated photocurrents can be optimized according to the two ways of porphyrin self‐assembly due to the “antenna effect”: changing the number of assembled porphyrin monolayers and the number of generations of the metal‐coordinated porphyrin networks.

Cis- and trans-dipyridylcalix[4]pyrroles were synthesized and cis-dipyridylcalix[4]pyrrole formed a supramolecular cage upon dimerization and coordination with Pd(II). The cage molecule recognised suberate selectively by hydrogen bonding to the two calix[4]pyrroles.