3-Amino-2-pyrazinecarboxylic acid → N-((R)-1-(6-(3-chlorophenylamino)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)ethyl)-3-aminopyrazine-2-carboxamide

関与物質

反応手順

(Steps 1-v & 1-yl) tert-Butyl (R)-1-(6-(3-chlorophenylamino)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)ethylcarbamate (110 mg, 0.28 mmol) was dissolved in 5 mL TFA/CH2Cl2 (1:1) and left standing for 20 min. The solvent was removed under reduced pressure and CH2Cl2 was added and removed 4 times to remove residual TFA. The resulting amine was dissolved in DMF and 3-aminopyrazine-2-carboxylic acid (200 mg, 1.4 mmol), HBTU (0.50 g, 1.3 mmol) and DIEA (1 mL, 5.7 mmol) were added. The reaction mixture was stirred at room temperature for 2 hours, then poured into ethyl acetate/0.1 M NaOH. The organic layer was dried over sodium sulfate and concentrated to yield an oil. This oil was purified by reversed-phase HPLC. Fractions containing pure product were concentrated to give N—((R)-1-(6-(3-chlorophenylamino)-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)ethyl)-3-aminopyrazine-2-carboxamide as a yellow solid (60 mg, 0.13 mmol, 48% yield): 1H NMR (500 MHz, DMSO-d6) 10.43 (s, 1H), 9.19 (d, J=8.1 Hz, 1H), 8.22-8.20 (m, 2H), 7.89 (t, J=2.0 Hz, 1H), 7.75-7.73 (m, 2H), 7.33 (m, 2H), 7.07 (dd, J=1.3, 7.9 Hz, 1H), 5.76-5.71 (m, 1H), 1.75 (d, J=6.9 Hz, 3H); MH+410.2.

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