[CH:1]([C:3]1[C:8]2[C:9]([CH3:12])=[CH:10][S:11][C:7]=2[CH:6]=[CH:5][C:4]=1[OH:13])=[O:2].[CH3:14][O:15][C:16]1[CH:21]=[C:20]([O:22][CH3:23])[N:19]=[C:18](S(C)(=O)=O)[N:17]=1.C(=O)([O-])[O-].[K+].[K+].O>CN(C)C=O>[CH3:14][O:15][C:16]1[CH:21]=[C:20]([O:22][CH3:23])[N:19]=[C:18]([O:13][C:4]2[CH:5]=[CH:6][C:7]3[S:11][CH:10]=[C:9]([CH3:12])[C:8]=3[C:3]=2[CH:1]=[O:2])[N:17]=1A mixture comprising 2.1 g of 4-formyl-5-hydroxy-3-methylbenzothiophene, 2.4 g of 4,6-dimethoxy-2-methylsulfonylpyrimidine and 1.8 g of potassium carbonate in 30 ml of N,N-dimethylformamide, was heated and stirred at 70° C. for 3 hours. The mixture was returned to room temperature, then poured into water and extracted with ethyl acetate. The organic layer was washed with water and then dried over anhydrous sodium sulfate. Then, it was concentrated under reduced pressure, and the oily substance thereby obtained was purified by silica gel column chromatography (n-hexane/ethyl acetate=10/1) to obtain 3.1 g (yield: 86%) of the desired compound.
불러오는 중…