[CH:1]([N:4]1[CH2:9][CH2:8][N:7]([C:10]2[C:11](=[O:16])[NH:12][CH:13]=[CH:14][N:15]=2)[CH2:6][CH2:5]1)([CH3:3])[CH3:2].CC([O-])(C)C.[K+].CS(O[CH2:28][CH2:29][O:30][C:31]1[CH:36]=[C:35]([F:37])[C:34]([F:38])=[CH:33][C:32]=1[F:39])(=O)=O.O>C1COCC1>[F:39][C:32]1[CH:33]=[C:34]([F:38])[C:35]([F:37])=[CH:36][C:31]=1[O:30][CH2:29][CH2:28][N:12]1[CH:13]=[CH:14][N:15]=[C:10]([N:7]2[CH2:6][CH2:5][N:4]([CH:1]([CH3:3])[CH3:2])[CH2:9][CH2:8]2)[C:11]1=[O:16]A mixture of 3-(4-isopropyl-1-piperazinyl)-2(1H)-pyrazinone (0.58 g, 2.6 mmol; from Step 2) and t-BuOK (440 mg, 3.90 mmol) in THF (40 mL) was stirred until the mixture became thick (about 10 min), and then a solution of 2-(2,4,5-trifluorophenoxy)ethyl methanesulfonate (0.90 g, 2.2 mmol; from Example 54, Step 4) in THF (10 mL) was added. After being stirred for 5 days at ambient temperature, HPLC showed only 25% conversion. The reaction solution was then heated to 60° C. overnight which gave almost full conversion. The reaction was worked up according to the following: water was added, THF was evaporated off and the aqueous mixture was extracted twice with EtOAc, dried and concentrated to yield 1.18 g of the crude product as a yellow oil. Purification by chromatography on silica gel (eluent: 2.5% MeOH in CHCl3+NH3 (g)) gave the title compound as a colourless oil, which solidified upon cooling. Yield: 120 mg (14%). HPLC purity: 99%. MS m/z 397 (M+H)+. HRMS m/z calcd for C19H23F3N4O2 (M)+ 396.1773, found 396.1771.
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