Preferential Recognition and Extraction to Pentoses over Hexoses by a D6h-Symmetrical Ethynylphenol Macrocycle with Six Inner Phenolic Hydroxy Groups.

A macrocycle consisting of six ethynylphenol units was developed as a host architecture for saccharides. The rigid framework of the macrocycle suppressed the intramolecular hydrogen-bonding between adjacent phenolic hydroxy groups and recognized saccharides by intermolecular hydrogen-bonding within the hole. The well-defined hydrogen-bonding sites enabled the size-selective guest recognition and showed preference to pentoses over hexoses.