[CH3:1][O:2][C:3](=[O:7])[CH:4](Br)[CH3:5].[CH:8]([S:11][C:12]1[C:17]([OH:18])=[CH:16][CH:15]=[CH:14][N:13]=1)([CH3:10])[CH3:9].C(=O)([O-])[O-].[K+].[K+].Cl>CN(C)C=O.C(OCC)(=O)C>[CH3:1][O:2][C:3](=[O:7])[CH:4]([O:18][C:17]1[C:12]([S:11][CH:8]([CH3:10])[CH3:9])=[N:13][CH:14]=[CH:15][CH:16]=1)[CH3:5]12.3 ml of 2-bromopropionic acid methyl ester are added dropwise at room temperature to a mixture of 16.9 g of 2-isopropylthio-3-hydroxypyridine and 15.2 g of potassium carbonate in 250 ml of dimethylformamide and the batch is stirred for 75 minutes. The suspension is introduced into a mixture of ice-water (300 ml), 50 ml of 2N hydrochloric acid and 300 ml of ethyl acetate, washed four times with 120 ml of water and 120 ml of ethyl acetate each time, and the organic phase is dried over sodium sulfate and concentrated by evaporation. 25.4 g of the desired intermediate are obtained in the form of a viscous oil.
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