Among them, MC3340 (6) (Figure 4) exhibited IC50LSD1 = 90 nM with selectivity over MAOs, and submicromolar potency against APL NB4 (IC50 = 0.6 μM) and AML MV4-11 (IC50 = 0.4 μM) cells (Fioravanti et al., 2020), and the 1S, 2R pure enantiomer 7 (Vianello et al., 2016) (Figure 4) showed IC50LSD1 = 84 nM, high selectivity over MAO-B, and huge anticlonogenic activity in mouse APL blasts and THP-1 cells. The gene discussed is MAOB; the disease is acute promyelocytic leukemia.