Angewandte Chemie International Edition
Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Picture (Angew. Chem. Int. Ed. Engl. 22/1997)
The cover picture shows a stick model of an aggregated calixarenoporphyrin derived from crystal-structrue coordinates (oxygen atoms of one molecule are represented in red, and nickel atoms as glass balls; the second molecule is depicted by fainter sticks). Aggregations of two molecules to give a cogwheel arragement is clearly a dominant structural phenomenon. Combination of calixarenes, which posses strong ion-bonding properties, with porphyrins, which are pH-dependent photoactive chromophores, can potentially lead to new molecular receptors for the development of efficent sensors. Calixarenoporphyrins may also serve as potential models for biological systems such as the tetrapyrrole units in the light-harvesting component of bacterial LH2. More about this suprmolecular array is reported by K. M. Smith and co-workers on pages 2497–2500. The graphic was generated by Philippe Schmitt, University of Oxford, UK, with the programs POV-Ray 3.0 and POV-Chem.