Synthesis of a series of unsaturated ketone derivatives as selective and reversible monoamine oxidase inhibitors

We have synthesized three categories of α,β-unsaturated carbonyl derivatives and evaluated their MAO-A and MAO-B inhibitory activities. Among them, compound 10b including α,β-unsaturated ketone group showed the most potent and selective MAO-B inhibitory activity (IC₅₀ human MAO-B 16 nM, >6000-fold selective vs MAO-A) and compound 10b exhibited good reversibility compared with selegiline, a well-known irreversible MAO-B inhibitor. However, both α,β-unsaturated amide and ester derivatives exhibited weaker MAO-B inhibition potencies. The docking studies provided insights into the possible binding modes and the key interaction sites of the synthesized MAO-B inhibitors.