Reaction Steps
This was prepared using the same procedure as for 4-(6-bromo-2-(4-(dimethylamino)phenyl)-3H-imidazo[4,5-b]pyridin-7-yl)-N-phenylpiperazine-1-carboxamide, but here using 5-bromo-3-nitro-4-(4-(pyridin-3-ylmethyl)piperazin-1-yl)pyridin-2-amine (50 mg, 0.13 mmol), DMF (0.15 mL), ethanol (0.85 mL), 1M Na2S2O4 (3 eq, 0.38 mmol, 0.38 mL) and 4-[(4-methylpiperazin-1-yl)methyl]benzaldehyde (1.1 eq, 0.14 mmol, 31 mg). After 6 h, concentration in vacuo and purification by preparative tlc (CH2Cl2-MeOH, 9:1) gave the product (15 mg, 21%) as a pale yellow solid; δH (500 MHz, DMSO-d6) 2.16 (s, 3H, CH3), 2.34-2.38 (m, 8H, 2× piperazine N(CH2)2), 2.62 (t, J=4.7 Hz, 4H, piperazine N(CH2)2), 3.52 (s, 2H, NCH2), 3.62 (s, 2H, NCH2), 3.70 (t, J=4.6 Hz, 4H, piperazine N(CH2)2), 7.39 (dd, J=7.6, 4.6 Hz, 1H, pyridine H-5), 7.45 (d, J=8.4 Hz, 2H, phenyl H-3 & H-5), 7.79 (dt, J=7.7, 1.8 Hz, 1H, pyridine H-4), 8.13 (d, J=8.3 Hz, 2H, phenyl H-2 & H-6), 8.23 (s, 1H, imidazo[4,5-b]pyridine H-5), 8.49 (dd, J=4.8, 1.7 Hz, 1H, pyridine H-6), 8.56 (d, J=1.6 Hz, 1H, pyridine H-2), 13.47 (s, br, 1H, imidazo[4,5-b]pyridine NH);
