Trifluoroacetic acid → 1-(2-(4-(2-Amino-5-bromo-3-nitropyridin-4-yl)piperazin-1-yl)ethyl)-3-phenylurea

Participants

Reaction Steps

This was prepared using the same procedure as for 5-bromo-3-nitro-4-(4-(1-(pyridin-2-yl)ethyl)piperazin-1-yl)pyridin-2-amine, but here using tert-butyl 4-(2-(3-phenylureido)ethyl)piperazine-1-carboxylate (1.1 eq, 0.43 mmol, 150 mg), TFA (1 mL) and CH2Cl2 (2 mL), then 5-bromo-4-chloro-3-nitropyridin-2-amine (103 mg, 0.29 mmol) in iPrOH (2 mL) and DIPEA (0.5 mL). Filtration and washing as previously described gave the product (190 mg, 95% for two steps) as a bright yellow solid; 1H-NMR (500 MHz, DMSO-d6) 2.45-2.65 (2 m, 4H, piperazine N(CH2)2), 3.08-3.17 (2 m, 6H, piperazine N(CH2)2 & CH2), 3.60-3.63 (m, 2H, CH2), 6.10 (br s, 1H, NH), 6.89 (t, J=6.9 Hz, 1H, phenyl H-4), 7.02 (br s, 2H, NH2), 7.21 (t, br, J=7.4 Hz, 2H, phenyl H-3 & H-5), 7.38 (d, J=7.5 Hz, 2H, phenyl H-2 & H-6), 8.17 (s, 1H, pyridine H-6), 8.66 (s, br, 1H, NH);

Provenance & Evidence