C[Si](C=[N+]=[N-])(C)C.[C:8]([C:11]1[CH:29]=[CH:28][C:14]2[CH:15]=[C:16]([C:18]3[O:23][C:22](=[O:24])[C:21]([CH3:25])=[C:20]([OH:26])[C:19]=3[CH3:27])[O:17][C:13]=2[CH:12]=1)([OH:10])=[O:9].[C:30](O)(=O)C>CO.C1(C)C=CC=CC=1>[CH3:25][C:21]1[C:22](=[O:24])[O:23][C:18]([C:16]2[O:17][C:13]3[CH:12]=[C:11]([C:8]([O:10][CH3:30])=[O:9])[CH:29]=[CH:28][C:14]=3[CH:15]=2)=[C:19]([CH3:27])[C:20]=1[OH:26]Trimethylsilyldiazomethane (2 M hexane solution, 85 μl) was added to a mixed solution of 6-(6-carboxybenzofuran-2-yl)-3,5-dimethyl-4-hydroxy-2H-pyran-2-one (50 mg) in MeOH (5 ml) and toluene (1 ml), and the mixture was stirred at room temperature for 10 minutes. After adding acetic acid to the reaction solution for quenching of the excess trimethylsilyldiazomethane, it was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (CH2Cl2/MeOH =9/1) to obtain 3,5-dimethyl-4-hydroxy-6-(6-(methoxycarbonyl) benzofuran-2-yl)-2H-pyran-2-one.
読み込み中…
