Nonplanar Macrocycle Consisting of Four Pyridine and Phenol Units Connected with Acetylene Bonds Displaying Preferential Binding to Maltoside over Monosaccharides

A nonplanar macrocycle consisting of four pyridine–acetylene–phenol units was developed as a host for saccharide guest molecules. The macrocycle was found to strongly associate with a lipophilic maltose derivative, with an association constant of 107 M–1, over monosaccharide derivatives, for which much smaller association constants were determined, ranging from 103 M–1 to 104 M–1. The macrocycle was found to adopt a boat-like conformation, encapsulating β-d-maltoside in a twisted manner through approximately seven intermolecular hydrogen bonds.