Molecular Recognition of Carbohydrates through Directional Hydrogen Bonds by Urea-Appended Porphyrins in Organic Media Financial support from CMDS (KOSEF) is gratefully acknowledged. Y.-H.K. thanks the Ministry of Education for the award of the BK 21 fellowship. We thank Dr. O. S. Lee for computational modeling. We also thank a referee for helpful suggestions.

Sugar receptors: Urea-appended porphyrins were the most effective binding agent for pyranosides in chloroform and still very effective even in the presence of hydroxylic cosolvents. The combination of a rigid porphyrin skeleton and acyclic, flexible, yet preorganized polar urea groups aligned in a rigid platform (see picture) enabled three-dimensional recognition of carbohydrates.