Exploring the binding ability of polyammonium hosts for anionic substrates: selective size-dependent recognition of different phosphate anions by bis-macrocyclic receptors

il lavoro descive e discute la capacità di tre sistemi ditopici, costituiti da due unità poliammoniche mecrocicliche separate da differenti spaziatori, di riconocere selettivamnete differenti anioni fosfato in soluzione acquosa al variare della distanza tra le due unità leganti poliammoniche. The paper reports on the binding ability in water of three different receptors constituted by two polyammonium binding units separated by different linkers. The distance between the two polyammonium binding units imposed by the spacer separating the two macrocyclic units determines different binding ability for mono-., di- and triphosphate.