Supramolecular chemistry, defined as the subject of study on the formation of new chemical structures by the self-assembly of molecular sub-units together through weak intermolecualr interactions, is at the foreland of the molecular sciences. The supramolecular building block as one of the important parts of supramolecular chemistry has been used for the rational design and syntheses of supramolecular compounds with novel structures and application. The intermolecular interactions and recognition mechanism ...