[CH3:1][O:2][C:3]1[C:8]([N+:9]([O-])=O)=[C:7]([NH:12][C:13]([C:15]2[O:19][N:18]=[C:17]([C:20]([CH3:23])([CH3:22])[CH3:21])[CH:16]=2)=O)[CH:6]=[C:5]([C:24]2[CH:29]=[CH:28][CH:27]=[CH:26][C:25]=2[C:30]([F:33])([F:32])[F:31])[N:4]=1>CC(O)=O.[Fe]>[C:20]([C:17]1[CH:16]=[C:15]([C:13]2[NH:9][C:8]3[C:3]([O:2][CH3:1])=[N:4][C:5]([C:24]4[CH:29]=[CH:28][CH:27]=[CH:26][C:25]=4[C:30]([F:33])([F:32])[F:31])=[CH:6][C:7]=3[N:12]=2)[O:19][N:18]=1)([CH3:23])([CH3:22])[CH3:21]A solution of 3-tert-butyl-isoxazole-5-carboxylic acid [2-methoxy-3-nitro-6-(2-trifluoromethyl-phenyl)-pyridin-4-yl]-amide (110 mg, 0.237 mmol, prepared as described in STEP C above) in AcOH (5 mL) was treated with iron powder (66.1 mg, 1.18 mmol), and the mixture was heated to 100° C. for 3 h. The AcOH was removed in vacuo. The residue was taken up in saturated aqueous NaHCO3 (50 mL) and extracted twice with EtOAc (50 mL). The combined organic extracts were dried over MgSO4 and concentrated in vacuo. The residue was purified on a 12-g SEPRA Si 50 SPE column (Flow rate=15 mL/min; Eluent=EtOAc-hexanes, 1:99 for 10 min, then 1:99 to 1:3 over 40 min). The chromatography was repeated as above to yield 2-(3-tert-butyl-isoxazol-5-yl)-4-methoxy-6-(2-trifluoromethyl-phenyl)-3H-imidazo[4,5-c]-pyridine as a white solid. Mass Spectrum (LCMS, APCI pos.): Calculated for C21H19N4O2F3: 417.1 (M+H). Measured: 417.1.
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