HCID 86738944、化合物 → HCID 86738945、化合物
反応式
[CH2:1]=[C:2]1[C@H:9]([CH3:10])[O:8][C@@H:5]([O:6]C)[CH2:4][C@@H:3]1[NH:11][C:12](=[O:17])[C:13]([F:16])([F:15])[F:14]>C(O)(=O)C.O>[CH2:1]=[C:2]1[C@H:9]([CH3:10])[O:8][CH:5]([OH:6])[CH2:4][C@@H:3]1[NH:11][C:12](=[O:17])[C:13]([F:16])([F:15])[F:14]参加物
4
実験手順
A solution of 0.51 g (2 mmol) of the intermediate VIII in 10 ml of acetic acid and 40 ml of water was heated at 100° C. for two hours, then evaporated to dryness to give 2,3,4,6-tetradeoxy-4-C-methylene-3-trifluoroacetamido-L-threo-hexopyranose (IX, 0.47 g, 99%) as a white solid: m.p. 168°-170° C., [α]D20° -160° (c=0.5, CHCl3). Treatment of IX (0.36 g, 1.5 mmol) in 25 ml of dry methylene dichloride with 4 ml of trifluoroacetic anhydride for 2 hours at 0° C. and 1 hour at 20° C. gave, after evaporation, the 1-0-trifluoroacetate (X), which was directly used for the preparation of the corresponding 1-chloro-derivative by treatment with dry hydrogen chloride in anhydrous diethyl ether at 0° C. After standing at 0° C. overnight, the reaction mixture was evaporated to dryness to give 2,3,4,6-tetradeoxy-4-C-methylene-3-trifluoroacetamido-L-threo-hexopyranosyl chloride (III-A, 0.35 g, 90%), suitable for the subsequent coupling reaction without further purification.