No abstract

Dynamic assembly is a powerful fabrication method of complex, functionally diverse molecular architectures, but its use in synthetic nanomachines has been hampered by the difficulty of avoiding reversible attachments that result in the premature breaking apart of loosely held moving parts. We show that molecular motion can be controlled in dynamically assembled systems through segregation of the disassembly process and internal translation to time scales that differ by four orders of magnitude. Helical molecular tapes were designed to slowly wind around rod-like guests and then to rapidly slide along them. The winding process requires helix unfolding and refolding, as well as a strict match between helix length and anchor points on the rods. This modular design and dynamic assembly open up promising capabilities in molecular machinery.

Winding and rewinding: How many times can helical aromatic oligomers wind around one another? At least four, as judged by the aggregation behavior of oligoamides based on 8‐fluoroquinoline (see scheme depicting the formation of a quadruple helix; red spheres: sites in the hollow space partially occupied by water molecules).

No abstract

A water-soluble fluorescent sensor, 1, based on the quinoline platform, demonstrates femtomolar sensitivity for zinc ion with a 14-fold enhanced quantum yield upon chelation to zinc ion and also exhibits high selectivity to zinc ion over other physiological relevant divalent metals in the presence of EDTA. X-ray crystal structure of zinc complex reveals that an acetic carboxylic group participates in coordination, which significantly enhances the affinity of 1 for zinc ion.

No abstract

New codes for sequence–structure–function relationships can be elaborated in aromatic oligoamide foldamers upon varying main‐chain components. Each monomer carries its own structural and functional features and enables oligomeric sequences to be designed to encapsulate specific guests.

In this manuscript, we present supramolecular capsules based on a new design relying on both self-assembly and folding of oligomeric strands. We have designed an aromatic amide foldamer in which each monomer encodes three levels of information: a specific cavity size, recognition groups for guest binding, and a propensity to adopt a single or a double helical motif. Thus, a tetradecameric sequence based on four different monomers was encoded so that a wide double helical segment resulting from the hybridization of two strands creates a cavity in which guests, such as 1,10-decanediol, can be bound. Additionally two narrow single helical segments form end-caps and isolate the guest from the solvent. The design, synthesis, solid-state and solution-state characterization of duplex formation and guest binding are presented.