Dynamic negative allosteric effect: regulation of catalysis multicomponent rotor speed.

Nanorotor R1 (420 kHz) was assembled from five components utilizing three orthogonal interactions. Post-modification at the distal position generated the advanced six component rotor R2 (45 kHz). The decrease in R2 speed leads to the inhibition of a three-component reaction by reducing catalyst release.

Interconversion between multicomponent slider-on-deck and palladium capsule: regulation of catalysis and encapsulation.

When the slider-on-deck [Cu(1)(2)] and guest G were treated with palladium(II) ions, the biped 2 was released from [Cu(1)(2)] generating the nanocage [Pd(2)(G)] with guest G being encapsulated (NetState-II). This transformation that was reversed by the addition of DMAP enabled modulation of both the overall fluorescence and the activity of copper(I) catalyzing an aza Hopf cyclization.

Chemically Fueled Logic AND Gate with Double Encoding in the Time Domain.

To increase information density and security in communication, Nature at times encodes signals in the time domain, for instance, Ca ion signals. Double encoding in the time domain operates beyond this level of security because the data are encoded in two time-dependent output signals showing distinct periods, frequencies, and full duration half-maxima. To illustrate such a protocol, a three-component ensemble consisting of a double ion-selective luminophore with two distinct receptor sites, hexacyclen, and diaza-18-crown-6 ether is demonstrated to act as a logic AND gate with Ag and Ca ions as inputs.

Fast and slow walking driven by chemical fuel.

We demonstrate the fast forward and slow backward motion of a biped on a tetrahedral track using chemical fuel, cooperative binding and kinetic selectivity. Walking of the biped is based on its dibenzyl amine feet that bind to zinc porphyrin units and, upon protonation, to dibenzo 24-crown-8 sites affording pseudorotaxane linkages.

Self-Healing of a Copper(I) [2]Rotaxane Shuttle Monitored by Fluorescence.

We demonstrate self-healing of the shuttling dynamics of a molecular machine operating by negative feedback. When zinc(II) was added to the copper(I)-loaded [2]rotaxane shuttle [Cu()], copper(I) was replaced, thereby generating the static zinc(II)-loaded [2]rotaxane [Zn()]. Loss of the dynamics was accompanied by a fluorescence enhancement at λ = 364 nm.

Parallel Allosteric Inhibition of Shuttling Motion and Catalysis in a Silver(I)-loaded [2]Rotaxane.

A dynamic silver(I)-loaded [2]rotaxane shuttle ( = 135 kHz) was converted allosterically into a conformationally restricted [2]rotaxane due to the creation of a bulky imine in the center of the axle component. Only the dynamic silver(I)-loaded [2]rotaxane was able to catalyze a 6--cyclization reaction, whereas the static one was catalytically quiet. The mechanism of catalyst deactivation was elucidated.

Catalytic machinery in motion: controlling catalysis speed.

Three 3-component copper(I)-based slider-on-deck systems served as catalysts for a click reaction showing a higher catalytic activity with increasing sliding speed. Upon addition of brake stones, the motion of the resulting 4-component machinery was slowed and eventually stopped (on the NMR time scale) with the effect that catalysis was reduced or obstructed.

Concurrent base and silver(I) catalysis pulsed by fuel acid.

Treatment of a crown-ether receptor and a silver(I)-loaded cyclam derivative (NetState-I) with a fuel acid reversibly afforded the protonated cyclam and the silver(I)-loaded crown ether (NetState-II). While NetState-I was catalytically OFF, a base-catalysed Michael addition and a silver(I)-catalysed oxime cyclisation reaction was pulsed under dissipative conditions in NetState-II.