[F:1][C:2]1[C:7]([F:8])=[CH:6][CH:5]=[CH:4][C:3]=1[C@:9]12[CH2:16][O:15][C@H:14]([CH2:17][O:18][C:19]([C:32]3[CH:37]=[CH:36][CH:35]=[CH:34][CH:33]=3)([C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)[C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=3)[C@H:13]1[CH2:12][O:11][NH:10]2>C(O)(=O)C.[Zn]>[NH2:10][C@@:9]1([C:3]2[CH:4]=[CH:5][CH:6]=[C:7]([F:8])[C:2]=2[F:1])[CH2:16][O:15][C@H:14]([CH2:17][O:18][C:19]([C:26]2[CH:27]=[CH:28][CH:29]=[CH:30][CH:31]=2)([C:32]2[CH:37]=[CH:36][CH:35]=[CH:34][CH:33]=2)[C:20]2[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=2)[C@H:13]1[CH2:12][OH:11]Zinc powder (10.1 g) was added to a suspension of (3aR,4S,6aS)-6a-(2,3-Difluorophenyl)-4-((trityloxy)methyl)tetrahydrofuro[3,4-c]isoxazole, obtained in Preparation Example 4-(22), (7.76 g) in acetic acid (75 ml) at RT. The mixture was stirred for 11.5 h at RT then the solid was removed by filtration through celite. The filtrate was concentrated in vacuo, then the residue was dissolved with EtOAc. 28% ammonia aqueous solution was added slowly, and the organic layer was separated, washed with brine, and dried over MgSO4. The solid was removed by filtration and the filtrate was concentrated under reduced pressure. Zinc powder (10.1 g) was added to the suspension of the residue in acetic acid (75 ml) at RT. After the mixture was stirred for 11.5 h at same temperature, the solid was removed by filtration through celite. The filtrate was concentrated in vacuo, then the residue was dissolved with EtOAc. 28% ammonia aqueous solution was added slowly, and the organic layer was separated, washed with brine, and dried over MgSO4. The solid was removed by filtration, and the filtrate was concentrated under reduced pressure. The crude mixture was purified by amino silica gel column chromatography (gradient from 50% to 100% EtOAc in heptane) to afford the titled compound (7.04 g) as a white solid. 1H-NMR (400 MHz, CDCl3) δ (ppm): 2.60-2.64 (m, 1H), 3.27 (d, J=4.8 Hz, 2H), 3.61-3.65 (m, 1H), 3.89-3.94 (m, 2H), 4.30 (d, J=9.2 Hz, 1H), 4.33-4.37 (m, 1H), 7.04-7.16 (m, 2H), 7.20-7.30 (m, 10H), 7.40-7.43 (m, 6H)
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