[CH:1]([O:4][C:5]1[CH:16]=[CH:15][C:8]([O:9][C:10]2[S:11][CH:12]=[CH:13][N:14]=2)=[CH:7][CH:6]=1)([CH3:3])[CH3:2].C([Li])CCC.CCCCCC.[I:28]I.S([O-])([O-])(=O)=S.[Na+].[Na+]>O1CCCC1.C(OCC)(=O)C>[I:28][C:12]1[S:11][C:10]([O:9][C:8]2[CH:15]=[CH:16][C:5]([O:4][CH:1]([CH3:3])[CH3:2])=[CH:6][CH:7]=2)=[N:14][CH:13]=1
To a solution of the product from Example 7A (1.52 g, 6.5 mmole) in tetrahydrofuran (80 mL) at −78° C. was added a solution of 2.5M n-butyl lithium in hexane (2.84 mL, 7.1 mmole) and stirred for 2 hours. Solid iodine (1.80 g, 7.1 mmole) was added and the mixture was allowed to warm up to room temperature for an hour. The reaction mixture was diluted with ethyl acetate and added an aqueous solution of 10% sodium thiosulfate. The ethyl acetate layer was dried over magnesium sulfate, dried over magnesium sulfate and filtered through silica gel to remove polar impurities. The silica gel was washed with ethyl acetate until no UV active spot was apparent on TLC plate. Evaporation of the solvent yielded the title compound as light-yellow oil, 2.30 g (Quantitative). 1H NMR (300 MHz, CDCl3) δ ppm 7.29 (s, 1H) 7.09-7.22 (m, 2H) 6.84-6.96 (m, 2H) 4.42-4.61 (heptet, J=5.88 Hz, 1H) 1.34 (d, J=5.88 Hz, 6H). MS (ESI) m/z 362 (M+H)+.
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