[Cl:1][C:2]1[C:3]([CH2:9][C:10]([OH:12])=O)=[N:4][CH:5]=[C:6]([Cl:8])[CH:7]=1.[CH3:13][O:14][C:15]([C:17]1[C:22]([NH2:23])=[N:21][CH:20]=[CH:19][N:18]=1)=[O:16].C(N(CC)CC)C.O=C1N(P(Cl)(N2CCOC2=O)=O)CCO1>ClCCl>[CH3:13][O:14][C:15]([C:17]1[C:22]([NH:23][C:10](=[O:12])[CH2:9][C:3]2[C:2]([Cl:1])=[CH:7][C:6]([Cl:8])=[CH:5][N:4]=2)=[N:21][CH:20]=[CH:19][N:18]=1)=[O:16]
To a solution of (3,5-dichloro-pyrid-2-yl)-acetic acid (Example 5.1) (5.7 g) and 3-amino-pyrazine-2-carboxylic acid methyl ester (4.65 g) in dichloromethane (120 ml) were added successively triethylamine (8.5 ml) and bis(2-oxo-3-oxazolidinyl)phosphinic chloride (“BOP-Cl”) (7.5 g). The reaction mixture was stirred at ambient temperature for 24 hours. The organic phase was washed successively with water, aqueous sodium hydrogen carbonate (1M), and brine. The organic phase was dried over magnesium sulfate and concentrated to give 3-[2-(3,5-dichloro-pyrid-2-yl)-acetylamino]-pyrazine-2-carboxylic acid methyl ester (6.37 g). 1H-NMR (400 MHz, CDCl3): 4.04 (s, 3H), 4.35 (s, 2H), 7.77 (s, 1H), 8.39 (s, 1H), 8.49 (s, 1H), 8.56 (s, 1H), 11.02 (s, 1H) ppm.
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