No abstract

One equivalent of Ca2+ and Sr2+ ions induces the isomerization of the colorless spirobenzopyrans 1a (n = 1) and 1b (n = 2), respectively, to the colored merocyanines 2. Compounds of type 1 thus function as ion‐selective chemical sensors.

New allosteric thymine receptors, 2,6-diamidopyridine derivatives tethered to an anthracene ring by a polyoxyethylene chain, were synthesized. In these receptors, binding of 1-butylthymine was enhanced by a factor of 4-6 by recognition of sodium cations, and the changes in the electron density of the anthracene ring were found to have influence on the allosterism by through-space interaction. The anthracene-linked diamidopyridines represent a rationally designed new class of artificial allosteric receptors.

No abstract

No abstract