Controlling the chair conformation of a mannopyranose in a large-amplitude [2]rotaxane molecular machine.

Molecular machines boarding now! Molecular machines containing dibenzo[24]crown-8 (DB24C8) and based on an anilinium and a pyridinium amide station have been prepared. The DB24C8 shuttles upon variation of pH and interacts differently with the pyridinium amide station depending on its substitution. When the DB24C8 sits around the disubstituted amide, the conformation of the pyranose changes from (1)C(4) to (4)C(1).