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-(1-(pyridin-3-yl)ethyl)piperazin-1-yl)pyridin-2-amine (300 mg, 0.73 mmol), DMF (4.4 mL), ethanol (0.6 mL), 1M Na2S2O4 (3 eq, 2.19 mmol, 2.19 mL) and 4-(N,N-dimethylamino)benzaldehyde (1.1 eq, 0.81 mmol, 121 mg). After 16 h, concentration in vacuo and column chromatography (EtOAc-DCM-MeOH, 50:50:2) gave the product (49 mg, 13%) as a pale yellow solid; 1H-NMR (500 MHz, DMSO-d6) 1.39 (d, J=6.6 Hz, 3H, CHCH3), 2.51-2.67 (2 m, 4H, piperazine N(CH2)2), 3.00 (s, 6H, N(CH3)2), 3.58-3.66 (m, 5H, piperazine N(CH2)2 & CHCH3), 6.81 (d, J=8.9 Hz, 2H, N,N-dimethylaminophenyl), 7.39 (dd, J=7.6, 4.8 Hz, 1H, pyridine H-5), 7.78 (d, br, J=7.7 Hz, 1H, pyridine H-4), 8.00 (d, J=8.9 Hz, 2H, N,N-dimethylaminophenyl), 8.13 (s, 1H, imidazo[4,5-b]pyridine H-5), 8.48 (d, br, J=4.4 Hz, 1H, pyridine H-6), 8.58 (br s, 1H, pyridine H-2), 13.11 (br s, 1H, imidazo[4,5-b]pyridine NH);
