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 (30 mg, 0.076 mmol), DMF (0.15 mL), ethanol (0.85 mL), 1M Na2S2O4 (3 eq, 0.23 mmol, 0.23 mL) and 4-(1,1-dioxothiomorpholino)benzaldehyde (1.1 eq, 0.084 mmol, 20 mg). After 6 h, concentration in vacuo and purification by preparative tlc (CH2Cl2-MeOH, 95:5) gave the product (14 mg, 32%) as a colourless solid; δH (500 MHz, DMSO-d6) 2.61 (s, br, 4H, piperazine N(CH2)2), 3.14 (t, J=4.7 Hz, 4H, 1,1-dioxothiomorpholine N(CH2)2), 3.61 (s, 2H, NCH2), 3.65 (t, J=4.6 Hz, 4H, piperazine N(CH2)2), 3.91 (t, J=5.0 Hz, 4H, 1,1-dioxothiomorpholine S(CH2)2), 7.16 (d, J=9.0 Hz, 2H, phenyl H-2 & H-6), 7.39 (dd, J=7.5, 4.8 Hz, 1H, pyridine H-5), 7.78 (dt, J=7.8, 1.9 Hz, 1H, pyridine H-4), 8.06 (d, J=9.0 Hz, 2H, phenyl H-3 & H-5), 8.18 (s, 1H, imidazo[4,5-b]pyridine H-5), 8.49 (dd, J=4.7, 1.8 Hz, 1H, pyridine H-6), 8.56 (d, J=1.6 Hz, 1H, pyridine H-2), 13.26 (s, br, 1H, imidazo[4,5-b]pyridine NH);
