Indanones As High‐Potency Reversible Inhibitors of Monoamine Oxidase

Recent reports document that α‐tetralone (3,4‐dihydro‐2H‐naphthalen‐1‐one) is an appropriate scaffold for the design of high‐potency monoamine oxidase (MAO) inhibitors. Based on the structural similarity between α‐tetralone and 1‐indanone, the present study involved synthesis of 34 1‐indanone and related indane derivatives as potential inhibitors of recombinant human MAO‐A and MAO‐B. The results show that C6‐substituted indanones are particularly potent and selective MAO‐B inhibitors, with IC₅₀ values ranging from 0.001 to 0.030 μM . C5‐Substituted indanone and indane derivatives are comparatively weaker MAO‐B inhibitors. Although the 1‐indanone and indane derivatives are selective inhibitors of the MAO‐B isoform, a number of homologues are also potent MAO‐A inhibitors, with three homologues possessing IC₅₀ values <0.1 μM . Dialysis of enzyme–inhibitor mixtures further established a selected 1‐indanone as a reversible MAO inhibitor with a competitive mode of inhibition. It may be concluded that 1‐indanones are promising leads for the design of therapies for neurodegenerative and neuropsychiatric disorders such as Parkinson’s disease and depression.