反应详情

To a solution of Boc-D-α-phenylglycine (2 mmol), L-proline benzyl ester hydrochloride (2.2 mmol), and DIPEA (5 mmol) in dry dichloromethane (10 mL) was added TBTU (2.2 mmol). The reaction mixture was stirred at room temperature overnight. The mixture was concentrated under vacuum and the residue was passed through a SCX-2 column and further chromatographied to yield compound 2a. 1H NMR (CDCl3, 400 MHz) δ (ppm) 1.40 (s, 9H), 1.76-1.82 (m, 1H), 1.92-2.07 (m, 3H), 3.09-3.15 (m, 1H), 3.70-3.77 (m, 1H), 4.47-4.51 (m, 1H), 5.16 (d, J=12.35 Hz, 1H), 5.23 (d, J=12.35 Hz, 1H), 5.43 (d, J=7.20 Hz, 1H), 6.12 (d, J=7.20 Hz, 1H), 7.27-7.41 (m, 10H); and MS (ESI, EI+) m/z=439 (MH+).

1. concentrationThe mixture was concentrated under vacuum