ClC(Cl)([O:4][C:5](=[O:11])[O:6]C(Cl)(Cl)Cl)Cl.[CH3:13][C:14]1[N:18]([CH2:19][CH2:20][OH:21])[C:17]([N+:22]([O-:24])=[O:23])=[CH:16][N:15]=1>CN(C1C=CN=CC=1)C.C(Cl)Cl>[CH3:13][C:14]1[N:18]([CH2:19][CH2:20][OH:21])[C:17]([N+:22]([O-:24])=[O:23])=[CH:16][N:15]=1.[C:5](=[O:4])([O-:11])[O-:6]mPEG3OH (1.0 mmol, 164 mg) and DMAP [4-(dimethylamino)pyridine, 2.4 mmol] were dissolved in anhydrous DCM (dichloromethane, 20 ml). Triphosgene (0.34 mmol, 99 mg) was added at room temperature. The solution was stirred at room temperature for 15 minutes. Metronidazole (1.0 mmol, 171 mg) was added and the reaction solution was stirred at room temperature for two hours. The solvent was evaporated at reduced pressure. The residue was subjected to flash chromatography (methanol/DCM=2˜5%) to obtain compound 2a (220 mg, yield 61%). 1H NMR (CDCl3) δ 7.99 (s, 1H), 4.61 (t, 2H), 4.50 (t, 2H), 4.28 (t, 2H), 3.73-3.40 (m, 10H), 3.40 (s, 3H), 2.53 (s, 3H). LC/MS 362 [M+H]+.
Wird geladen…