C([C@H]1COC(=O)N1[C:14](=[O:26])[C@H:15]([CH2:19][CH2:20][CH2:21][CH2:22][CH2:23][CH2:24][CH3:25])[CH2:16][CH:17]=[CH2:18])C1C=CC=CC=1.[OH:27]O.O[Li].O>C1COCC1.O>[CH2:19]([C@H:15]([CH2:16][CH:17]=[CH2:18])[C:14]([OH:26])=[O:27])[CH2:20][CH2:21][CH2:22][CH2:23][CH2:24][CH3:25]To a solution of 8.69 g (0.024 mol) of the product from Example 3 in 425 mL of THF/H2O (3:1), cooled to 0 degrees, was added 10.8 mL (0.097 mol) of 30% hydrogen peroxide solution followed by 2.03 g (0.049 mol) of LiOH-H2O. The resulting solution was stirred at 0° C. for 1.5 h and then quenched with a solution of 15.4 g of sodium sulfite in 100 mL of H2O. The reaction mixture was then acidified to pH 3 with aqueous HCl and extracted with EtOAc. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:10) to provide 4.33 g (90%) of the desired product as a colorless oil. CI Mass Spec: 199 (M+H).
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