反应详情

To a solution of Example 267A (0.500 g, 1.86 mmol) in methanol (20 mL) at ambient temperature was added D-valinol (0.20 mL, 1.9 mmol) and acetic acid (0.40 mL, 7.4 mmol) followed by MP-cyanoborohydride (2.49 mmol/g; 1.0 g). After 2 hours, the mixture was filtered, concentrated and the residue partitioned between ether and 1M NaOH. The organic extract was concentrated and purified by chromatography to provide 390 mg (59%) of the title compound. MS (DCI+) m/z 270 (M+H); 1H NMR (500 MHz, CDCl3) δ 8.28 (dd, J=6.8, 2.0 Hz, 1H), 8.24-8.15 (m, 1H), 7.76 (t, J=7.7 Hz, 1H), 7.61 (d, J=7.8 Hz, 1H), 7.34-7.25 (m, 2H), 4.04 (q, J=14.5 Hz, 2H), 3.70 (dd, J=10.9, 4.0 Hz, 1H), 3.49 (dd, J=10.8, 6.9 Hz, 1H), 2.53 (td, J=6.7, 4.1 Hz, 1H), 1.97-1.85 (m, 1H), 1.04 (d, J=6.8 Hz, 3H), 0.97 (d, J=6.9 Hz, 3H).

1. filtrationthe mixture was filtered
2. concentrationconcentrated
3. customthe residue partitioned between ether and 1M NaOH
4. extractionThe organic extract
5. concentrationwas concentrated
6. custompurified by chromatography