This issue contains two Reviews: L. Latos-Grażyński et al. describe the conformations and aromaticity of porphyrinoids; S. Saito and A. Osuka discuss structures, electronic properties, and reactivities of expanded porphyrins. In an Essay, M. O. Senge looks back on the development of porphyrin isomers since the days of Calvin and Pauling. Another look back is offered by the late E. Vogel on his own research from small carbon rings to porphyrins. The Highlights deal with the activation of CO2 (U.-P. Apfel and W. Weigand), the conversion of methane and oxygen to synthesis gas (W. F. Maier) and the derivatization of 5-hydroxymethylcytosine in DNA (C. Höbartner).
In the Communications section, A. J. Tasiopoulos et al. present a double-decker-wheel [Mn32] cluster (see picture). T. Ando et al. succeeded in monitoring the structural changes following illumination of bacteriorhodopsin by high-speed AFM. K. Tanaka et al. describe a rhodium-catalyzed asymmetric formal olefination or cycloaddition of 1,6-diynes and 1,6-enynes.