Synthetic Monosaccharide Channels: Size‐Selective Transmembrane Transport of Glucose and Fructose Mediated by Porphyrin Boxes

Here we report synthetic monosaccharide channels built with shape‐persistent organic cages, porphyrin boxes (PBs), that allow facile transmembrane transport of glucose and fructose through their windows.PBs show a much higher transport rate for glucose and fructose over disaccharides such as sucrose, as evidenced by intravesicular enzyme assays and molecular dynamics simulations. The transport rate can be modulated by changing the length of the alkyl chains decorating the cage windows. Insertion of a linear pillar ligand into the cavity ofPBs blocks the monosaccharide transport. In vitro cell experiment shows thatPBs transport glucose across the living‐cell membrane and enhance cell viability when the natural glucose transporter GLUT1 is blocked. Time‐dependent live‐cell imaging and MTT assays confirm the cyto‐compatibility ofPBs. The monosaccharide‐selective transport ability ofPBs is reminiscent of natural glucose transporters (GLUTs), which are crucial for numerous biological functions.