[F:1][C:2]([F:29])([F:28])[S:3]([NH:6][C:7]1[CH:12]=[CH:11][CH:10]=[C:9]([CH2:13][C:14]2[C:23](=[O:24])[C:22]3[C:17](=[CH:18][CH:19]=[C:20]([O:25]C)[CH:21]=3)[O:16][C:15]=2[CH3:27])[CH:8]=1)(=[O:5])=[O:4].Br.C(O)(=O)C.O>ClCCl.CO>[F:28][C:2]([F:1])([F:29])[S:3]([NH:6][C:7]1[CH:12]=[CH:11][CH:10]=[C:9]([CH2:13][C:14]2[C:23](=[O:24])[C:22]3[C:17](=[CH:18][CH:19]=[C:20]([OH:25])[CH:21]=3)[O:16][C:15]=2[CH3:27])[CH:8]=1)(=[O:4])=[O:5]A mixture of 2.1 g (4.91 mmole) of the product from Example 125, 25 mL 48% hydrobromic acid and 25 mL glacial acetic acid was refluxed for 18 hours. The mixture was poured into a stirred slurry of ice and water and stirred for 1 hour. The mixture was filtered, and the filtrant washed with water and dried to give a solid. Flash chromatography on silica gel eluting with 5% methanol in dichloromethane afforded 1.89 g (93%) the title product as a solid, mp 232°-234° C.
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