Bis-15-crown-5-ether-pillar[5]arene K+-Responsive Channels

An artificial selective K+ channel is formed from the supramolecular organization on bis(benzo-15-crown-5-ether-ureido)-pillar[5]arene compound. This channel achieves a selectivity of SK+/Na+, = 5 for an initial transport rate of k(K+) = 3.2 X 10(-3) s(-1). The cation -file diffusion occurs via selective macrocyclic-filters anchored on inactive suppofting pillar[5]-arene relays. The sandwich-type binding geometry of the K+ cation by two 15-crown-5 moieties sites is a key feature influencing channel efficiency.