Binding of Alkali Metal Ions by Cyclic Polyethers: Significance in Ion Transport Processes

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Science  25 Apr 1969:
Vol. 164, Issue 3878, pp. 443-444
DOI: 10.1126/science.164.3878.443


Values for the formation constant (log K), the change in enthalpy (▵H°), and the change in entropy (▵S°) have been determined for the interaction of lithium, sodium, potassium, rubidium, and cesium ions with the two isomers of the cyclic polyether, 2,5,8,15,18,21-hexaoxatricyclo[,14] hexacosane. The stability order of these metal ions with either isomer is identical to the permeability order for these same metal ions with the structurally related antibiotics, valinomycin and monactin.