While searching for new anti-Parkinson agents, we previously reported compound 3 (alias NW-1772, compound 22b in ref. [10]) that behaved as a highly selective (SI, IC50 MAO A/IC50 MAO B = 457) and in vivo potent rat MAO B inhibitor, with affinity in the nanomolar range (IC50 rat MAO B = 13 nM), rapid blood–brain barrier penetration, and poor CYP450s liability. The gene discussed is MAOB; the disease is Parkinsonism.