Potassium Carbonate → 5-Methyl-6-carboethoxy-7-amino-1H-pyrrolo[2,3-b]pyrazine

Beteiligte Stoffe

Reaktionsschritte

2-Chloro-3-cyanopyrazine (0.808 g, 5.79 mmol), prepared by the method of Shneller, et. al., J. Het. Chem., 12:513 (1975), was dissolved in 30 ml DMF under nitrogen and treated with sarcosine ethyl ester hydrochloride (0.978 g, 6.37 mmol) followed by K2CO3 (1.68 g, 12.16 mmol) at rt. The reaction mixture was gently refluxed for 36 h after which the cooled solution was partitioned between water and CHCl3. The aqueous phase was extracted with CHCl3 and the combined organics washed with water then brine and dried over Na2SO4. Concentration gave a green-black oil that was purified by chromatography on silica gel eluting with a gradient from 3:1 to 1:1 hexanes:ethyl acetate to give 0.40 g (31%) of the title compound as an orange solid. mp: 119°-121° C. 1H NMR (300 MHz, CDCl3) δ1.47 (t, 3H), 4.01 (s, 3H), 4.46 (q, 2H), 5.65 (br s, 2H), 8.32 (d, 1H), 8.38 (d, 1H). MS (DCI/NH3) m/e 220 (M+H)+. Analysis calc'd. for C10H12N4O2: C, 54.54; H, 5.49; N, 25.44; Found: C, 54.29; H, 5.52; N, 25.42.

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