'Purposive' molecular design for multifunctional artificial receptors

This account describes recent examples of multifunctional artificial receptors, which demonstrates our approach to purposive molecular design. The paper is divided into two parts. The first deals with novel crowned spirobenzopyrans as dual-mode signal transducers. The new crowned spirobenzopyrans complement previous crowned spirobenzopyrans from the viewpoint of molecular devices, and a detailed comparison between them is given. The second part is concerned with polypyridine-macrocyclic structures as ribofuranoside receptors. The design of the ribofuranoside receptors was based on the multipoint hydrogen bond complementarity between the receptors and methyl β-(D)-ribofuranoside. The binding affinity of the receptors was very high, so that even native ribose was extracted by them into nonpolar solvents.