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Securing a Supramolecular Architecture by Tying a Stopper Knot.

ABSTRACT: We report on a rotaxane-like architecture secured by the in?situ tying of an overhand knot in the tris(2,6-pyridyldicarboxamide) region of the axle through complexation with a lanthanide ion (Lu3+ ). The increase in steric bulk caused by the knotting locks a crown ether onto the thread. Removal of the lutetium ion unties the knot, and when the axle binding site for the ring is deactivated, the macrocycle spontaneously dethreads. When the binding interaction is switched on again, the crown ether rethreads over the 10?nm length of the untangled strand. The overhand knot can be retied, relocking the threaded structure, by once again adding lutetium ions.

SUBMITTER: Leigh DA

PROVIDER: S-EPMC6099318 | biostudies-other | 2018 Aug

REPOSITORIES: biostudies-other

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Securing a Supramolecular Architecture by Tying a Stopper Knot.

Leigh David A DA Pirvu Lucian L Schaufelberger Fredrik F Tetlow Daniel J DJ Zhang Liang L

Angewandte Chemie (International ed. in English) 20180527 33

We report on a rotaxane-like architecture secured by the in situ tying of an overhand knot in the tris(2,6-pyridyldicarboxamide) region of the axle through complexation with a lanthanide ion (Lu<sup>3+</sup> ). The increase in steric bulk caused by the knotting locks a crown ether onto the thread. Removal of the lutetium ion unties the knot, and when the axle binding site for the ring is deactivated, the macrocycle spontaneously dethreads. When the binding interaction is switched on again, the c ...[more]

PMID: 29708636

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