A solution of 2-(3-fluoro-2-methylquinoxalin-5-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (126) (46 mg, 0.16 mmol), (1-methylcyclopropyl)methanamine hydrochloride (37.8 mg, 0.310 mmol) (Princeton Bio, Princeton, N.J.), and DIEA (136 μL, 0.776 mmol) in DMSO (1.5 mL) was heated at 100° C. for 1.5 h. The crude product was diluted in DMSO (˜20 mg/mL) and injected (3×1.0 mL) onto the Shimadzu preparatory LC (Phenomenex Gemini C18, 10 μm, 150×30 mm; 10-100% MeCN/water with 0.1% TFA); the pure fractions were combined, basicified with NaHCO3 (saturated, aq.), extracted with DCM, separated, dried over Na2SO4, and concentrated via rotary evaporation to give 2-(2-methyl-3-(((1-methylcyclopropyl)methyl)amino)quinoxalin-5-yl)-6,7-dihydro-1H-pyrrolo[3,2-c]pyridin-4(5H)-one (335) (5 mg, 0.014 mmol, 9% yield). 1H NMR (400 MHz, DMSO-d6) δ ppm 0.25-0.29 (m, 2H) 0.57-0.62 (m, 2H) 1.20 (s, 3H) 2.56 (s, 3H) 2.89 (t, J=6.75 Hz, 2H) 3.45 (td, J=6.75, 2.35 Hz, 2H) 3.57 (d, J=5.87 Hz, 2H) 6.97 (br. s., 1H) 7.14 (d, J=1.96 Hz, 1H) 7.19 (t, J=5.87 Hz, 1H) 7.32 (t, J=7.82 Hz, 1H) 7.57 (dd, J=8.02, 1.17 Hz, 1H) 7.87 (dd, J=7.53, 1.08 Hz, 1H) 12.04 (br. s., 1H). MS (ESI, pos. ion) m/z: 362.1 (M+1).
