反应详情

3-(3-Methylphenylsulfonyl)amino-6-isopropyl-1-(carboxymethyl)-2-pyridinone (0.71 g, 1.95 mmol), as prepared in the preceding step, Castro's reagent (BOP, 0.905 g, 2.05 mmol), and [N,N′-di(tert-butoxycarbonyl)] 2-aminoethoxyguanidine (0.710 g, 2.00 mmol), as prepared in step 4 of Example 2, were dissolved in methylene chloride (40 mL) and reacted with triethylamine (0.75 mL, 5.4 mmol) at ambient temperature for 3 days. After concentration in vacuo, the crude product was dissolved in methylene chloride, washed with 10% aqueous citric acid, saturated NaHCO3, and brine, dried over Na2SO4, and filtered. The evaporated filtrate was purified by flash column chromatography (5% methanol in methylene chloride) giving the title compound as a light yellow solid (0.70 g, 54%). 1H NMR (300 MHz, CDCl3) δ9.15 (s, 1H), 8.34 (br t, 1H, J=5.0 Hz), 7.67 (m, 3H), 7.59 (s, 1H), 7.40 (d, 1H, J=7.9 Hz), 7.34 (m, 2H), 6.06 (d, 1H, J=7.9 Hz), 4.86 (s, 2H), 4.09 (m, 2H), 3.58 (dd, 2H, J=8.8 Hz, 5.0 Hz), 2.86 (m, 1H), 2.38 (s, 3H), 1.52 (s, 9H), 1.47 (s, 9H), 1.20 (s, 3H), 1.17 (s, 3H).

1. customas prepared in step 4 of Example 2
2. concentrationAfter concentration in vacuo
3. dissolutionthe crude product was dissolved in methylene chloride
4. washwashed with 10% aqueous citric acid, saturated NaHCO3, and brine
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. customThe evaporated filtrate was purified by flash column chromatography (5% methanol in methylene chloride)