[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[C:7]([C:9]1([C:14]2[CH:15]=[C:16]([CH3:20])[CH:17]=[CH:18][CH:19]=2)[CH2:13][CH2:12][CH2:11][O:10]1)=[O:8].[BH4-].[Na+]>CO>[CH3:20][C:16]1[CH:15]=[C:14]([C:9]2([CH:7]([C:2]3[CH:3]=[CH:4][CH:5]=[CH:6][N:1]=3)[OH:8])[CH2:13][CH2:12][CH2:11][O:10]2)[CH:19]=[CH:18][CH:17]=1To a solution of Example 91D (478 mg, 1.79 mmol) in methanol (10 mL) was added NaBH4 (135 mg, 3.55 mmol) portion wise, and the mixture was stirred overnight at room temperature. After evaporating most of the solvent, the residue was diluted with 10 mL of water, and extracted with ethyl acetate (15 mL×3). The combined organic phases was dried over Na2SO4, filtered, and concentrated. The residue was purified by prep-TLC (petroleum ether:ethyl acetate=3:1) to give the title compound (182.7 mg, 38%). LC-MS: m/z (M+H): 270. 1H NMR (400 MHz, CDCl3): δ ppm 8.27 (d, J=4.4 Hz, 1H), 6.93-7.59 (m, 7H), 4.83 (d, J=6.0 Hz, 1H), 4.63 (d, J=6.0 Hz, 1H), 3.87-4.07 (m, 2H), 2.60-2.65 (m, 1H), 2.28-2.31 (m, 1H), 2.21 (s, 3H), 1.79-1.92 (m, 2H).
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