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-phenyl piperazine-1-carboxamide, but here using 5-bromo-3-nitro-4-(4-(pyridin-3-ylmethyl)piperazin-1-yl)pyridin-2-amine (20 mg, 0.051 mmol), DMF (0.15 mL), ethanol (0.85 mL), 1M Na2S2O4 (3 eq, 0.15 mmol, 0.15 mL) and 4-(4-methylpiperazino)benzaldehyde (1.1 eq, 0.056 mmol, 11 mg). After 6 h, concentration in vacuo and purification by preparative tlc (CH2Cl2-MeOH, 9:1) gave the product (11 mg, 39%) as a colourless solid; δH (500 MHz, DMSO-d6) 2.26 (s, 3H, CH3), 2.49 (s, br, 4H, piperazine N(CH2)2), 2.63 (s, br, 4H, piperazine N(CH2)2), 3.30 (hidden by DMSO peak, 4H, piperazine N(CH2)2), 3.62 (s, 2H, NCH2), 3.65 (t, J=4.2 Hz, 4H, piperazine N(CH2)2), 7.06 (d, J=8.7 Hz, 2H, phenyl H-3 & H-5), 7.40 (dd, J=7.7, 4.8 Hz, 1H, pyridine H-5), 7.79 (d, br, J=7.7 Hz, 1H, pyridine H-4), 8.03 (d, J=8.7 Hz, 2H, phenyl H-2 & H-6), 8.18 (s, 1H, imidazo[4,5-b]pyridine H-5), 8.50 (d, J=4.5 Hz, 1H, pyridine H-6), 8.57 (s, br, 1H, pyridine H-2), 13.22 (s, br, 1H, imidazo[4,5-b]pyridine NH);
