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(A) One calix[4]resorcinarene subunit. (B) A crystal structure of 89b, comprised of six calix[4]resorcinarene subunits and eight water molecules. Adapted with permission from ref 80c. Copyright 2004 American Chemical Society. (C) Energy-minimized structure of tetraheptylammonium bromide encapsulated within 88b. Methyl substituents omitted for clarity. Image adapted from ref. 80a.
