An Allosteric Receptor by Simultaneous “Casting” and “Molding” in a Dynamic Combinatorial Library

Allosteric synthetic receptors are difficult to access by design. Herein we report a dynamic combinatorial strategy towards such systems based on the simultaneous use of two different templates. Through a process of simultaneous casting (the assembly of a library member around a template) and molding (the assembly of a library member inside the binding pocket of a template), a Russian‐doll‐like termolecular complex was obtained with remarkable selectivity. Analysis of the stepwise formation of the complex indicates that binding of the two partners by the central macrocycle exhibits significant positive cooperativity. Such allosteric systems represent hubs that may have considerable potential in systems chemistry.     

Response to “Comments on a Possible Transition to Solid‐Phase Homochirality”

As part of an ongoing discussion comparing models for the evolution of homochirality, we address the preceding Correspondence by Ribó and co‐workers. We demonstrate that our previous Concept article did not include errors concerning solubility behavior and we address the challenge of representing equilibrium phase behavior for systems of racemizing enantiomers. In addition we re‐emphasize the point that the homochiral state is not inherently more stable than the heterochiral state and we show that concerning this point the Ribó treatise misinterprets the Frank model for the evolution of homochirality.     

Polymer Brushes by the “Grafting to” Method

This paper focuses on the attachment of densely grafted polymer layers (polymer brushes) to various inorganic and polymeric substrates by the “grafting to” method. A brief overview of synthesis of polymer brushes by the method is first provided, with emphasis on chemical approaches to polymer attachment. The second part of the paper covers the synthesis of polymer layers via a recently developed macromolecular anchoring layer approach. Several examples of application of the grafting technique are presented for generation of hydrophobic, hydrophilic, gradient, and switchable surfaces.