A ‘toothpaste tube’ model for ion transport through trans-membrane channels

Abstract

The X-ray crystal structure of the 2 : 1 Na⁺ complex of the hexahomooxacalix[3]arene diethylamide derivative 1b shows capsular and nesting inclusion of the two Na⁺ cations suggesting a mechanism by which Na⁺ and K⁺ ions are desolvated and pass through biological ion channels.

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