||Salen complexes are widely employed in catalysis and biomedical science and chiral salen complexes are among the most important catalysts for asymmetric synthesis. Their reduced counterparts, containing two N-amine donor atoms instead of N-imines, often designated by salan compounds, yield much more stable complexes and M(salan) systems present many advantages regarding the sustainability of the catalytic processes and their use as anti-cancer drugs. Although being more easily recovered than M(salen) compounds, M(salan) are much more flexible molecules and it is often not easy to control their selectivity in catalytic reactions. In contrast, some salan compounds are cytotoxic and their metal complexes are much more hydrolytically stable than the corresponding M(salen) s making them potentially more effective and adequate compounds both in vitro and in vivo. It is, thus, feasible that in the near future this type of coordination compounds will yield therapeutic drugs able to treat cancers resistant to Pt-based drugs. (C) 2019 Published by Elsevier B.V.