Toluene → HCID 23353228, compound

Participants

Reaction Steps

Ethyl 3-aminothieno[2,3-b]pyrazine-2-carboxylate (0.43 g, 1.9 mmol) prepared by the method of Schneller and Clough, J. Het. Chem., 12: 513 (1975), triphosgene (0.13 g, 0.43 mmol), triethylamine (0.44 mL, 3.2 mmol), and toluene were stirred at 25° C. for 2 h and then heated to near reflux. Triethylamine hydrochloride was removed by filtration and the filtrate was concentrated. The residue and the product from Example 79A (0.44 g, 1.6 mmol) were taken up in a small amount of toluene. After refuxing for 18 h, the reaction was concentrated and chromatographed (10% EtOH in CH2Cl2) to provide 0.24 g (3 1%) of the title compound which was converted to the HCl salt: m.p. 185° (dec); 1H NMR (300 MHz, CD3OD) δ1.63-1.98 (m, 6H), 2.69-2.85 (m, 3H), 3.20-3.41 (m, 4H), 3.60-3.82 (m, 2H), 3.84 (s, 3H), 4.11-4.16 (m, 3H), 6.77 (d, 1H), 6.81 (d, 1H), 7.16 (t, 1H), 8.77 (d, 1H), 8.84 (d, 1H); MS (DCI/NH3) m/e 478 (M+H)+; Analysis calc'd for C25H27N5O3S.HCl.H2O: C, 56.43; H, 5.68; N, 13.16; found: C, 56.00; H, 5.46; N, 12.78.

Provenance & Evidence