[CH:1]1([CH2:7][CH2:8][CH2:9][C@@H:10]([C:19]2[O:23][N:22]=[C:21]([CH2:24][O:25][CH2:26][C:27]([O:29][CH2:30][CH3:31])=[O:28])[N:20]=2)[CH2:11][C:12]([O:14]C(C)(C)C)=[O:13])[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1.FC(F)(F)C(O)=O>ClCCl>[CH:1]1([CH2:7][CH2:8][CH2:9][C@@H:10]([C:19]2[O:23][N:22]=[C:21]([CH2:24][O:25][CH2:26][C:27]([O:29][CH2:30][CH3:31])=[O:28])[N:20]=2)[CH2:11][C:12]([OH:14])=[O:13])[CH2:6][CH2:5][CH2:4][CH2:3][CH2:2]1A solution of tert-butyl (3R)-6-cyclohexyl-3-{3-[(2-ethoxy-2-oxoethoxy)methyl]-1,2,4-oxadiazol-5-yl}hexanoate (Preparation 86) (500 mg, 1.08 mmol) in dichloromethane (7 ml) was treated with trifluoroacetic acid (3 ml) and stirred at room temperature for 5 hours. The solvent was removed under reduced pressure and the residue azeotroped from toluene and dichloromethane. The oil was purified by column chromatography on silica gel eluting with a gradient system of 100:0:0 (dichloromethane:methanol:acetic acid) gradually changing to 90:10:1 (dichloromethane:methanol:acetic acid) to afford the title compound as a colourless oil (374 mg).
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