In this issue, M. R. Buchmeiser et al. review carbon fibers: What precursor systems exist, how are they processed, and what structures and properties result? In a Minireview, A. Y. Hong and B. M. Stoltz discuss the chemical and biosynthesis of presilphiperfolanol natural products. The Highlight by U. F. Müller and Y. Tor deals with citric acid and the RNA world.

In the Communications section, R. M. Bullock et al. demonstrate heterolytic hydrogen cleavage by an iron hydrogenase model (see picture). C. Duboc et al. succeeded in a bio-inspired switch of a Co^II₂ disulfide/Co^III thiolate system. P. Guilbaud et al. elucidated the structure of organic solutions by a combination of molecular dynamics simulations and X-ray scattering and A. Pfaltz et al. present an asymmetric hydrogenation of maleic acid diesters and anhydrides.

• Angewandte Chemie: Strength and Flexibility,
  Angew. Chem. Int. Ed. 2014, 53(21).