Metronidazole → Metronidazole Carbonate

mPEG21OH (0.21 mmol, 200 mg) and DMAP (1.0 mmol) were dissolved in anhydrous DCM (10 ml). Triphosgene (0.13 mmol, 39 mg) was added at room temperature. The solution was stirred at room temperature for 5 minutes. Metronidazole (1.0 mmol, 171 mg) was added and the reaction solution was stirred at room temperature overnight. The solvent was evaporated at reduced pressure. The residue was extracted with EtOAc/H2O (20 ml/20 ml) three times. The aqueous phases were combined and adjusted to PH 4.0 by adding 0.1N HCl solution. The solution was extracted with DCM (3×20 ml). The organic phases were combined and dried with anhydrous Na2SO4. The solid was filtered off and the solvent was evaporated to give compound 2d (220 mg, yield 90%). 1H NMR (CDCl3) δ 7.89 (s, 1H), 4.53 (t, 2H), 4.43 (t, 2H), 4.19 (t, 2H), 3.63-3.46 (m, 80H), 3.31 (s, 3H), 2.45 (s, 3H). LC/MS 1154 [M+H]+.

1. stirringthe reaction solution was stirred at room temperature overnight
2. customThe solvent was evaporated at reduced pressure
3. extractionThe residue was extracted with EtOAc/H2O (20 ml/20 ml) three times
4. additionby adding 0.1N HCl solution
5. extractionThe solution was extracted with DCM (3×20 ml)
6. dry with materialdried with anhydrous Na2SO4
7. filtrationThe solid was filtered off
8. customthe solvent was evaporated

ORD record

ord-6dfc758d078741ab9d749cb28c8a67ef

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09233932B2