Front Cover: Synthesis of Cytotoxic Iron‐Containing Macrocycles Through Unexpected C(sp²)−C(sp²) Bonds Formation (Eur. J. Inorg. Chem. 23/2023)

The Front Cover shows a representation of stomach cancer cells being destroyed by an iron(II) complex bearing a tetradentate ligand. Gastric cancer is associated with a high mortality rate and high lethality and is frequently resistant to standard chemotherapies and immunotherapy. A cutting-edge reaction between Fe3(CO)12 and brominated or mercurated pincer derivatives promotes the formation of carbon−carbon bonds, and a 16-electron iron(II) complex with a tetradentate ligand originating from the dimerization of 6-phenyl-2,2′-bipyridine and a protonated 14-membered macrocycle from 2,6-diphenyl-pyridine were obtained. These new compounds are cytotoxic towards stomach cancer cells. Thanks to the presence of the iron center, the biological activity dramatically increased, and the complex was 5-fold more toxic than cisplatin on AGS cells. The cover was designed by Carolina Torres-Gutiérrez (the first author) and Hortensia Segura Silva. More information can be found in the Research Article by R. Le Lagadec and co-workers.