[S:1]1[C:5]([CH2:6][N:7]2[CH2:12][CH2:11][N:10]([C:13](OC(C)(C)C)=O)[CH2:9][CH2:8]2)=[CH:4][N:3]=[CH:2]1.C(O)(C(F)(F)F)=O.[Br:27][C:28]1C(Cl)=[C:30]([N+:35]([O-:37])=[O:36])[C:31]([NH2:34])=[N:32][CH:33]=1>C(Cl)Cl>[Br:27][C:28]1[C:13]([N:10]2[CH2:9][CH2:8][N:7]([CH2:6][C:5]3[S:1][CH:2]=[N:3][CH:4]=3)[CH2:12][CH2:11]2)=[C:30]([N+:35]([O-:37])=[O:36])[C:31]([NH2:34])=[N:32][CH:33]=1tert-Butyl 4-(thiazol-5-ylmethyl)piperazine-1-carboxylate (0.350 g, 1.23 mmol, 1.1 eq) was dissolved in DCM (3.9 mL) and the mixture cooled in a ice-water bath before the dropwise addition of TFA (3.9 mL). Stirring was continued at this temperature for 1 h. Solvents were removed in vacuo and the resulting crude material was azeotroped with toluene and dried. The resulting 5-(piperazin-1-ylmethyl)thiazole (supposedly 0.230 g, 1.23 mmol, 1 eq) was suspended in iPrOH (2.4 mL) and DIPEA (0.70 mL). To this solution, 5-bromo-4-chloro-3-nitropyridin-2-amine (0.280 g, 1.12 mmol, 1 eq) was added and the mixture was heated and stirred for 17 h at 65° C. The mixture was filtered, washed with iPrOH (3×3 mL), Et2O (2×3 mL) and dried to give the title compound as a bright yellow powder (0.330 g, 67%); 1H-NMR (500 MHz, DMSO-d6): δ 2.51-2.58 (br s, 4H, piperazine N(CH2)2), 3.01-3.10 (m, 4H, piperazine N(CH2)2), 3.82 (s, 2H, NCH2), 6.98 (s, 2H, NH2), 7.78 (s, 1H, thiazole 4-H), 8.16 (s, 1H, pyridine 6-H), 9.03 (s, 1H, thiazole 2-H); LC (Method B)-MS (ESI, m/z): Rt=2.17 min—399/401 [(M+H+), Br isotopic pattern, 100%].
読み込み中…
