The rotary motor in Fig. comprises a cyclic track with two degenerate binding sites (distinguishable by one being labelled with deuterium) for a macrocycle. Fluorenylmethoxycarbonyl (Fmoc) groups, that sterically prevent passage of the macrocycle, can be attached to hydroxy residues on the track (Fig. ). When only one barrier is in place, macrocycle shuttling enables exchange between two co-conformers ("co-conformers" are structures that differ in the relative positions of the components ) that have the macrocycle either proximal or distal to the free hydroxy group. The fueling reaction kinetically discriminates between the two co-conformers, favoring the reaction of the distal co-conformer over the proximal co-conformer. Under basic conditions, the waste-forming reaction removes barriers without any chemical gating. The chemical gating afforded by the biased fueling reaction, and the free energy supplied by the fuel-to-waste conversion, result in directional movement of the macrocycle around the track. The rotary motor can be represented by a chemomechanical network of reactions (Fig. ) in which mechanical and chemical transitions are coupled, as in common models for biological molecular motors and minimal Brownian motors with external dichotomous noise . Since no transitions enable simultaneous change in the mechanical and chemical state, this network is said to be bipartite.