Antivitamins B(12)—Some Inaugural Milestones

The recently delineated structure‐ and reactivity‐based concept of antivitamins B(12) has begun to bear fruit by the generation, and study, of a range of such B(12)‐dummies, either vitamin B(12)‐derived, or transition metal analogues that also represent potential antivitamins B(12) or specific B(12)‐antimetabolites. As reviewed here, this has opened up new research avenues in organometallic B(12)‐chemistry and bioinorganic coordination chemistry. Exploratory studies with antivitamins B(12) have, furthermore, revealed some of their potential, as pharmacologically interesting compounds, for inducing B(12)‐deficiency in a range of organisms, from hospital resistant bacteria to laboratory mice. The derived capacity of antivitamins B(12) to induce functional B(12)‐deficiency in mammalian cells and organs also suggest their valuable potential as growth inhibitors of cancerous human and animal cells.