Engineered Supramolecular Chirality of a Bioderived Macrocycle by an Orthogonal Assembly Strategy

Macrocyclic compounds demonstrate excellent potential in host–guest recognition and self-assembly. However, especially for cavitands, their bulky three-dimensional geometry often hinders self-assembly into ordered one-dimensional arrays. The inclusion of guest molecules and host–guest interactions can further disrupt this order, making it challenging to express supramolecular chirality. Herein, we introduce an orthogonal assembly strategy to construct a three-component modular chiral assembly. Biotin[6]uril, a hexameric macrocycle featuring six peripheral carboxyl chains and a medium-size cavity, is employed. This unique structure allows it to orthogonally complex with two distinct types of guests simultaneously. Leveraging a combination of host–guest and hydrogen-bonding interactions, Biotin[6]uril complexes the dye molecule within its cavity and melamine via its peripheral carboxyl groups, respectively. The synergistic interplay among these three assembly modules, particularly the multiple hydrogen-bonding interactions between melamine and carboxyl, successfully induces the expression of chirality at both supramolecular and macroscopic levels. This system exploits the synergistic advantage of the inner cavity and the peripheral groups of macrocycles. It opens an avenue for the design and application of macrocyclic molecules in the field of multifunctional chiral materials.