C([O:4][C@@H:5]1[C@H:9]([O:10]C(=O)C)[C@@H:8]([CH3:14])[O:7][C@H:6]1[N:15]1[CH:28]=[C:27]([F:29])[C:19]([NH:20][C:21]([O:23][CH2:24][CH2:25][CH3:26])=[O:22])=[N:18][C:16]1=[O:17])(=O)C.[OH-].[Na+].CO.Cl>C(Cl)Cl>[F:29][C:27]1[C:19]([NH:20][C:21]([O:23][CH2:24][CH2:25][CH3:26])=[O:22])=[N:18][C:16](=[O:17])[N:15]([CH:28]=1)[C@@H:6]1[O:7][C@H:8]([CH3:14])[C@@H:9]([OH:10])[C@H:5]1[OH:4]To a solution of 2',3'-di-O-acetyl-5'-deoxy-5-fluoro-N4 -(propoxycarbonyl)cytidine (2.5 g) in CH2Cl2 (17 ml) was added dropwise 1N NaOH (17 ml) with stirring and cooling with ice bath. After stirring for 1 hr at 0° C., MeOH (0.9 ml) was added to the mixture. And pH of the reaction mixture was adjusted to 6 by the addition of concentrated HCl and partitioned. The aqueous layer was extracted with a mixed solvent of CH2Cl2 /MeOH(95/5) successively (40 ml×10). The combined organic layers were dried over anhydrous sodium sulfate and filtered. The solution was evaporated, and the residue was crystallized from ethyl acetate to give 5'-deoxy-5-fluoro-N4 -(propoxycarbonyl)cytidine as colorless crystals (1.6 g, y. 79.8%): mp. 125°-126.5° C.; EI-MS m/z 331 (M+).
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