C([O:3][C:4](=[O:40])[C:5]1[CH:10]=[CH:9][CH:8]=[C:7]([O:11][CH2:12][CH2:13][CH2:14][N:15]2[C:19]3[CH:20]=[CH:21][CH:22]=[CH:23][C:18]=3[N:17]([CH2:24][C:25]3[CH:30]=[CH:29][CH:28]=[C:27]([Br:31])[CH:26]=3)[C:16]2=[N:32][C:33]([O:35][C:36]([CH3:39])([CH3:38])[CH3:37])=[O:34])[CH:6]=1)C.O[Li].O>C1COCC1.CO.O>[Br:31][C:27]1[CH:26]=[C:25]([CH:30]=[CH:29][CH:28]=1)[CH2:24][N:17]1[C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][C:19]=2[N:15]([CH2:14][CH2:13][CH2:12][O:11][C:7]2[CH:6]=[C:5]([CH:10]=[CH:9][CH:8]=2)[C:4]([OH:40])=[O:3])[C:16]1=[N:32][C:33]([O:35][C:36]([CH3:38])([CH3:39])[CH3:37])=[O:34]To a solution of 3-(3-{3-(3-bromo-benzyl)-2-[tert-butoxycarbonylimino]-2,3-dihydro-benzoimidazol-1-yl}-propoxy)-benzoic acid ethyl ester (155 mg, 0.25 mmol) in THF (2 ml), MeOH (2 ml) and H2O (1 ml) was added LiOH.H2O (53 mg, 1.27 mmol). The reaction was warmed to 40° C. where it was maintained for 20 h. After this time, the reaction was cooled to rt concentrated under reduced pressure and then partitioned between EtOAc and 1M HCl. The organic phase was separated and the aqueous phase was extracted with additional EtOAc. The combined organic layers were washed with brine, dried (Na2SO4), filtered and concentrated under reduced pressure to provide 3-(3-{3-(3-bromo-benzyl)-2-[tert-butoxycarbonylimino]-2,3-dihydro-benzoimidazol-1-yl}-propoxy)-benzoic acid (150 mg, 100%). HPLC-MS 580, 582 [M+1]+.
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